Top Banner
Assessing the sustainability of bioethanol production in Nepal DILIP KHATIWADA Licentiate Thesis in Energy Technology Energy and Climate Studies Stockholm, Sweden 2010 DILIP KHATIWADA Assessing the sustainability of bioethanol production in Nepal KTH 2010 www.kth.se ISBN 978-91-7415-769-7 TRITA-ECS 2010-01
79

Dissertation on Sugar Production in Nepal

Aug 30, 2014

Download

Documents

Kelvin Bartley
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1: Dissertation on Sugar Production in Nepal

Assessing the sustainability of bioethanol production

in Nepal

D i l i p K h at i wa D a

licentiate thesis in Energy technologyEnergy and Climate Studies

Stockholm, Sweden 2010

Dilip Kh

atiwa

Da assessing the sustainability of bioethanol production in N

epalKth

2010www.kth.se

ISBN 978-91-7415-769-7TRITA-ECS 2010-01

Page 2: Dissertation on Sugar Production in Nepal

Assebioeth

D

KTH Sch

essing thhanol p

Dilip

Licen

Division of EDepartment

hool of IndustSTOCK

he sustaproducti

p Khatiw

ntiate Thesis 2

nergy and Clit of Energy Ttrial Engineer

KHOLM, SW

ainabilition in N

wada

2010

limate StudiesTechnology ring and Man

WEDEN

ty of Nepal

s

nagement

Page 3: Dissertation on Sugar Production in Nepal

ISBN 978-91-7415-769-7

TRITA-ECS 2010-01

© Dilip Khatiwada

Page 4: Dissertation on Sugar Production in Nepal

I

Abstract

Access to modern energy services derived from renewable sources is a prerequisite, not only for economic growth, rural development and sustainable development, but also for energy security and cli-mate change mitigation. The least developed countries (LDCs) primarily use traditional biomass and have little access to commer-cial energy sources. They are more vulnerable to problems relating to energy security, air pollution, and the need for hard-cash cur-rency to import fossil fuels. This thesis evaluates sugarcane-molasses bioethanol, a renewable energy source with the potential to be used as a transport fuel in Nepal.

Sustainability aspects of molasses-based ethanol have been ana-lyzed. Two important indicators for sustainability, viz. net energy and greenhouse gas (GHG) balances have been used to assess the appropriateness of bioethanol in the life cycle assessment (LCA) framework. This thesis has found that the production of bioetha-nol is energy-efficient in terms of the fossil fuel inputs required to produce it. Life cycle greenhouse gas (GHG) emissions from pro-duction and combustion are also lower than those of gasoline. The impacts of important physical and market parameters, such as sug-ar cane productivity, the use of fertilizers, energy consumption in different processes, and price have been observed in evaluating the sustainability aspects of bioethanol production.

The production potential of bioethanol has been assessed. Con-cerns relating to the fuel vs. food debate, energy security, and air pollution have also been discussed. The thesis concludes that the major sustainability indicators for molasses ethanol in Nepal are in line with the goals of sustainable development. Thus, Nepal could be a good example for other LDCs when favorable governmental policy, institutional set-ups, and developmental cooperation from donor partners are in place to strengthen the development of re-newable energy technologies.

Keywords: Bioethanol, sustainability, life cycle assessment, net energy values, greenhouse gas (GHG) balances, sustainable development, least developed countries (LDCs), Nepal

Page 5: Dissertation on Sugar Production in Nepal

II

Preface

This thesis has been developed in the Division of Energy and Cli-mate Studies (ECS), Department of Energy Technology at KTH – School of Industrial Engineering and Management, within the framework of the Global Energy and Climate Studies Program, supported by the Swedish Energy Agency. Research at ECS has an interdisciplinary character with a strong systems-based approach dealing with cross-cutting issues of sustainable energy systems, viz. energy, climate change and sustainable development. Research at ECS is currently focused on bioenergy systems, rural electrifica-tion, and energy and climate policy.

In this thesis, the sustainability paradigm of bioethanol production, with regard to environmental stewardship, economic prosperity, and social integrity is dealt with in relation to one of the world’s least developed countries (LDCs), Nepal. It is important to analyze the sustainability criteria of the renewable bioenergy systems when LDCs are living with energy and food poverty and myriad resource pressures, whilst endeavouring to sustain their livelihoods and achieve the goals of sustainable development.

This Licentiate thesis has been written as part of an ongoing PhD program in the assessment of sustainable bioenergy systems at a regional and global level. The evaluation of bioethanol production with methodological improvements aimed at finding international common ground is the next step in the research.

Page 6: Dissertation on Sugar Production in Nepal

III

Publications

The current licentiate thesis is based on the following publications which are appended at the end of the thesis:

I. Paper - I: Khatiwada, D., Silveira S., 2009. Net energy balance of molasses based ethanol: The case of Nepal. Renewable and Sustainable Energy Reviews 13, pp. 2515-2524 [Available online at Elsevier's www.sciencedirect.com]

II. Paper - II: Khatiwada, D., Silveira S., 2010. Greenhouse gas balances of molasses based ethanol in Nepal (under review, Journal of Cleaner Production). Revised manuscript of this paper is appended in the thesis.

III. Paper - III: Silveira, S., Khatiwada, D., 2010. Ethanol produc-tion and fuel substitution in Nepal—Opportunity to promote sustainable development and climate change mitigation. Re-newable and Sustainable Energy Reviews 14, pp. 1644-1652 [Available online at Elsevier's www.sciencedirect.com]

Page 7: Dissertation on Sugar Production in Nepal

IV

Acknowledgements

First of all, I would like to express my profound gratitude and sin-cere appreciation to my thesis supervisor Prof. Dr. Semida Silveira for inviting me to join her research team at ECS as a PhD student and for her superb guidance and creative suggestions regarding my research work. This thesis would have not come together in this form without her continuous supervision.

I would also like to thank my colleagues Brijesh, Francis, Maria, Tomas and Henrique at the Division of Energy and Climate Stud-ies (ECS). Furthermore, I extend my special thanks to Mr. Johan-nes Morfeldt for his generous support and necessary assistance during this thesis period.

I appreciate the work of Dr. Peter Hagström (KTH) for accepting to review this thesis, and providing valuable inputs. My sincere thanks also go to Dr. Andrew Martin, my thesis co-supervisor, who has provided special assistance and guided me a lot during my Master’s degree, as the program director.

I would like to thank the Swedish Energy Agency for providing partial funding, as a part of the Global Energy and Climate Studies Program, to allow me to complete my licentiate thesis.

Last but not least, I thank my wife, Ruchita and my beloved son, Shreyash for their endurance, love, encouragement and moral sup-port even from a great distance, in my home country – Nepal.

Page 8: Dissertation on Sugar Production in Nepal

V

Abbreviations and Nomenclature ADP Anaerobic Digestion Process BEFS Bioenergy and Food Security CDM Cleaner Development Mechanism CH4 Methane CHP Combined Heat and Power CO2 Carbon Dioxide CO2eq Carbon Dioxide Equivalent COD Chemical Oxygen Demand E10 10% ethanol and 90 % gasoline (v/v) E20 20% ethanol and 80% gasoline (v/v) E5 5% ethanol and 95 % gasoline (v/v) Ef Lower Heating Value of Fuel ethanol Ei Primary Energy Inputs ESCAP The United Nations Economic and Social

Commission for Asia and the Pacific EtOH Ethanol (>99.5% v/v), E100 or MOE ETP Effluent Treatment Plant EU European Union FAO United Nations Food and Agricultural Or-

ganization GHG Greenhouse Gas GJ Giga Joule GoN Government of Nepal Ha Hectare, also ha HC Hydro-Carbon HHV Higher Heating Value IAEA International Atomic Energy Agency IEA International Energy Agency IPCC Intergovernmental Panel on Climate

Change ISO International Standards for Organization K2O Potash Kcal Kilocalorie kg Kilogram kgCO2eq kg Carbon Dioxide Equivalent KJ/kg Kilo Joule per Kilogram KL Kilo-liter koe Kilogram of Oil Equivalent ktoe Kilo-tonnes of Oil Equivalent kW Kilowatt

Page 9: Dissertation on Sugar Production in Nepal

VI

kWh Kilowatt-hour L Liter LCA Life Cycle Assessment LDCs Least Developed Countries LHV Lower Heating Value LPG Liquefied Natural Gas m-3 Per Cubic Meter m3 Cubic Meter MDGs Millennium Development Goals MJ Mega-joule MJL-1 Mega-joule per Liter MJ-1 Per Mega-joule MOE Molasses Based Ethanol or EtOH MW Mega Watt N Nitrogen N2O Nitrous Oxide NEB Net Energy Balance or NEV NEi Non-Renewable or Fossil Fuel Inputs NEV Net Energy Value or NEB

Nm3 Normal Cubic Meter NOC Nepal Oil Corporation NREV Net Renewable Energy Value or Balance NRs Nepalese Currency Rupees OECD Organisation for Economic Co-operation

and Development ON Octane Number P2O5 Phosphorous PS Pond Stabilization or Lagoon System SRSM Sri Ram Sugar Mills Pvt. Ltd. Tonne 1000 kilogram (kg) TPES Total Primary Energy Supply UNDP United Nations Development Program UNFCCC United Nations Framework Convention on

Climate Change US United States of America USD ($) US Dollar v/v Volume by Volume w/w Weight by Weight WECS Water and Energy Commission Secretariat

Page 10: Dissertation on Sugar Production in Nepal

VII

Table of Contents

ABSTRACT I

PREFACE II

TABLE OF CONTENTS VII INDEX OF FIGURES VIII INDEX OF TABLES IX

1 INTRODUCTION 1 1.1 BACKGROUND 1 1.2 THESIS OBJECTIVE 5 1.3 RESEARCH QUESTIONS AND HYPOTHESES 5 1.4 SCOPE AND LIMITATIONS 6 1.5 ORGANIZATION OF THE STUDY 7

2 STATE-OF-ART TECHNOLOGIES IN BIOETHANOL PRODUCTION AND UTILIZATION 9

2.1 BIOFUELS – AN OVERVIEW 9 2.2 BIOETHANOL PRODUCTION 12 2.3 BIOETHANOL AS A TRANSPORT FUEL 14

3 SUSTAINABILITY CRITERIA AND LIFE CYCLE ASSESSMENT – CONCEPTS AND FRAMEWORKS 16

3.1 OVERVIEW 16 3.2 DEFINING SUSTAINABLE DEVELOPMENT AND SUSTAINABILITY 16 3.3 DEFINING LIFE CYCLE ASSESSMENT (LCA) 20 3.4 INTEGRATING SUSTAINABILITY AND LCA 21 3.5 DEVELOPMENT OF SUSTAINABILITY CRITERIA FOR BIOETHANOL

PRODUCTION 23 3.5.1 Identification of sustainability indicators for bioethanol in

Nepal 24 3.5.2 Defining net energy and greenhouse gas (GHG) balances 26 3.5.3 Realization of a case study – sensitivity analysis and

development of scenarios 28

4 RESULTS AND DISCUSSIONS 34 4.1 OVERVIEW 34 4.2 LIFE CYCLE NET ENERGY BALANCES AND TOTAL ENERGY YIELD

RATIO 34 4.2.1 Sensitivity analysis (net energy balances) 37

4.3 LIFE CYCLE GHG BALANCES AND AVOIDED EMISSIONS 39 4.3.1 Sensitivity analysis (GHG balances) 42 4.3.2 Alternative scenarios and system expansion 44

Page 11: Dissertation on Sugar Production in Nepal

VIII

4.4 COMPARISON OF RESULTS WITH OTHER STUDIES 48 4.5 PROSPECTS FOR SUSTAINABLE DEVELOPMENT 50 4.5.1 Ethanol production potential in Nepal 50 4.5.2 Substituting gasoline with E10 and E20 in the Kathmandu

Valley 50 4.5.3 Environmental gains of introducing E10 and E20 in the

Kathmandu Valley 51 4.5.4 Other important aspects of sustainable development 52

4.6 RESULTS OF SUSTAINABILITY ASSESSMENT: A SUMMARY SHEET 54

5 CONCLUSIONS AND FUTURE WORK 56 5.1 CONCLUSIONS 56 5.2 FUTURE WORKS 59

6 REFERENCES 60

I n d e x o f F i g u r e s

Figure 1: Simplified layout of sugarcane bioenergy systems in Nepal 7

Figure 2: Layout of the thesis 8

Figure 3: The production of biofuels from different biomass sources 10

Figure 4: Production routes of bioethanol 13

Figure 5: The three pillars of sustainability and their interaction in the sustainable energy system 18

Figure 6: Integration of LCA and sustainability assessment 22

Figure 7: System boundary and material flows (per hectare) for sugarcane-based systems in Nepal 31

Figure 8: Realization of the case study in Nepal: sugarcane farming and factory operations 33

Figure 9: The contribution of fossil and renewable energy required to produce 1 liter of EtOH (MOE) in Nepal, at each stage of the ethanol production chain 37

Figure 10: Effect of changes in the price of molasses on NEV, NREV, and the energy yield ratio 38

Page 12: Dissertation on Sugar Production in Nepal

IX

Figure 11: Effect of different levels of energy consumption at the ethanol plant on NEV values 39

Figure 12 : Sensitivity analysis for life cycle GHG emissions and avoided emissions (%) as a function of different allocation ratios for sugar and molasses 42

Figure 13: Sensitivity analysis for variations in material/energy inputs and sugarcane yield in Nepal 43

Figure 14: Life cycle emissions in the case of partial treatment of wastewater in PS and ADP 45

Figure 15: Life cycle emissions in the case of biogas leakage 46

Figure 16: GHG emissions shares from different stages of the ethanol production chain in Nepal (in the case of using surplus electricity to substitute diesel) 47

I n d e x o f t a b l e s Table 1: Selected sustainability criteria for evaluating the

appropriateness of bioethanol production and use in transport – the case of Nepal 25

Table 2: Primary energy requirement of one hectare of sugarcane farmland in Nepal (40.61 tonne/ha) 35

Table 3: Primary energy balance of sugar milling in Nepal (including distillation, dehydration and ETP) 36

Table 4: GHG emissions from sugarcane farm land per hectare in Nepal (sugarcane yield: 40.61 tonne/ha) 40

Table 5: Life cycle GHG (CO2eq) balance of molasses-based ethanol (MOE, EtOH) fuel in Nepal 41

Table 6: Life cycle comparison of GHG emissions, ethanol (EtOH) and gasoline 41

Table 7: Evaluating selected sustainability criteria for bioethanol production and use in Nepal – Summary of thesis results 55

Page 13: Dissertation on Sugar Production in Nepal

1

1 In t roduc t ion

1 . 1 B a c k g r o u n d

The continuous depletion of limited fossil fuel reserves, the global agenda on climate change and threats to energy security have led to increased global interest in the exploration, production and uti-lization of biofuels in the transport sector. Bioenergy systems have been drawn to the attention of policy makers since they reduce de-pendence on fossil fuel, contribute to rural and sustainable devel-opment, and are carbon-neutral. Reasons to promote biofuels in-clude energy security, environmental concerns, foreign exchange savings and socio-economic well-being of rural dwellers (Demirbas, 2008). Rising oil prices and energy security issues are the source of serious concerns in developing and least developed countries (LDCs) while climate change has led to the development of a global agenda that is also promoting renewable energy (UNIDO, 2006).

Modern liquid biofuels are seen as promising transport fuels in re-lation to reducing environmental impacts and improving energy security. Today, the transport sector consumes about 30% of the world’s total primary energy consumption and is one of the major contributors to global greenhouse gas (GHG) emissions. Increased use of fossil-fuel-based motorized transportation in urban areas of developing countries has not only exacerbated problems of local air pollution, but also poses energy security threats and high eco-nomic costs (Creutzig and He, 2009; Yan and Crookes, 2010). Least developed countries (LDCs), which basically depend on tra-ditional forms of energy (e.g. biomass) and have little access to commercial energy sources (e.g. electricity and liquid fuels) for their economic activities, are particularly vulnerable to issues sur-rounding energy security, air pollution, and the sustainability of their development. In addition, they cannot afford the cost of im-porting fossils fuels.

The least developed countries (LDCs) are characterized by low-income, weak human resources/assets, and high economic vulner-ability. Their populations suffer severe distress in the face of rising

Page 14: Dissertation on Sugar Production in Nepal

2

food and energy prices (UNCTAD, 2009). To achieve the Millen-nium Development Goals (MDGs), proper energy services need to be guaranteed for the poor (UNMCLDC, 2007). Indeed, access to modern energy services, sustainability (e.g. deforestation, land use, natural environment, and GHG emissions) and energy security are three areas that LDCs need to address to reach the MDGs (UN-MCLDC, 2007).

Traditional fuel consumption contributes 78.3% of the total energy in LDCs, while the figures for developing and OECD countries are 26.3% and 4.6% respectively (UNDP, 2006). Commercial en-ergy (coal, oil, and electricity) consumption in LDCs was only 67 koe (kg of oil equivalent) per capita in 2004 while other developing countries consumed 718 koe (UNCTAD, 2008). In Asia and the Pacific (ESCAP), half of the countries, including LDCs, land-locked developing countries and small island developing states are categorized as being more vulnerable with regard to energy securi-ty and sustainable development. The total final energy consump-tion of the least developed countries (LDCs) is only 47.02 thou-sand ktoe, compared to a total of 2,992 thousand ktoe in the ES-CAP, whilst the contribution of liquid fuels in LDCs is only 6.1 thousand, out of a total of 912 thousand ktoe in the region (UN-ESCAP, 2008). Moreover, LDCs have few resources for financing infrastructure. The average value of domestic resources available for financing governance and investment was only 41 cents per capita in LDCs compared to $3.2 and $36.4 in lower-middle and high-income countries respectively (UNCTAD, 2009).

However, there is huge potential for developing modern bioenergy in LDCs. According to Batidzirai et al., (2006), there is a large bio-energy potential in Mozambique that can be harnessed without compromising food demand and creating deforestation. FAO (2010) evaluated suitable pathways for developing biofuel produc-tion in conjunction with food security and poverty reduction as a way of realizing the enormous potential of biofuels in Tanzania. In African LDCs, average commercial energy consumption per capita was only 30.4 koe compared to 313 koe (kg of oil equivalent) in Africa as a whole (UNIDO, 2008). Thus, LDCs lack a basic supply of modern energy services and the financial resources to invest in them. Although they still only constitute a limited market for commercial liquid fuels for transportation, and are the lowest emit-

Page 15: Dissertation on Sugar Production in Nepal

3

ters of GHGs, LDCs are highly vulnerable to global warming and its related consequences (Huq et al., 2003).

Bioethanol has been used in the transport sector as a substitute for conventional gasoline. Bioethanol helps to reduce the use of fossil fuels, and to mitigate against climate change, while also promoting the socio-economic transformation of developing societies. Bio-ethanol already contributes 90% of the total biofuel market in the world, and its production could be significantly increased, particu-larly in sugar producing countries, where it can be used to replace fossil fuels (Balat et al., 2008; Balat and Balat, 2009). However, the production of biofuels has been debated in the context of envi-ronmental performance, food versus energy security and land use, among others.

Nepal, a least developed and landlocked country in South Asia, does not have fossil fuel reserves. Nepal’s total primary energy supply (TPES) system is dominated by the use of traditional bio-mass (87.71%), followed by fossil fuels (9.94%), hydroelectricity (1.82%), and renewable sources 0.53% (WECS, 2006). The transport sector is the largest consumer of petroleum products. Kathmandu Valley, the capital city alone, consumes about 70% of the total imported gasoline. This area is also the place where 56% of the total number of vehicles run. Vehicular emissions are a ma-jor source of air pollution in the Valley, and its bowl-shaped to-pography tends to exacerbate local pollution problems. The accu-mulation of foreign debts for oil imports, at a rising cost, the fre-quent shortage of transport fuels, public unrest due to rises in the subsidized price of petroleum products, and alarming air pollution have contributed to the initiation of discussions about alternative sources of transport fuel in the Kathmandu Valley. Increasing for-eign debts have also put pressure on the national economy as they divert money away from the scarce developmental budget of the country.

As a result, the Government of Nepal (GoN) decided to blend 10% ethanol with gasoline (in 2004), and formed a high level committee with the task of finding energy alternatives to reduce oil consumption (in 2008). One of the sugarcane factories, Sri Ram Sugar Mills Pvt. Ltd. (SRSM) has also constructed an ethanol plant in Nepal. However, the potential of ethanol production has not yet

Page 16: Dissertation on Sugar Production in Nepal

4

been realized due to conflicting economic, technical and political issues, and a lack of promising trust amongst major stakeholders.

Least developed countries (LDCs) have not yet harnessed their huge potential in producing ethanol from sugarcane systems. However, in recent times, they have been showing interest in the development and deployment of sugarcane bioenergy in an effort to reduce dependence on imported fuels and enhance domestic energy security, as is the case with Nepal. Both private and public sectors are willing to promote this commercial biofuel. Interna-tional cooperation on the climate change agenda could also help to initiate work in sustainable sugarcane bioenergy systems in LDCs, such as the Bioenergy and Food Security (BEFS) program in Tan-zania (FAO, 2010). Versteeg (2007) has evaluated the environmen-tal sustainability of sugarcane-bioethanol production in Fiji, a small island developing state in the Pacific, estimating reductions in life cycle GHG emissions, net energy balances, and ecological foot-prints in the context of sustainable development. The feasibility study focused on how to select LDCs to produce bioethanol in an effective and sustainable way, indicating that surplus cane sugar, dependency on imported fuels, and economic production potential are the key selection criteria (DSDG, 2005). UNDESA (2007) has also discussed the technical, socio-economic, and environmental benefits of small scale biofuel production as a means of promoting sustainable development in sub-Saharan Africa, focusing on the poor’s access to energy, the reduction of oil imports, income gen-eration, rural development and the improvement of local environ-mental pollution. However, detailed analyses of the production of bioethanol have not been carried out for LDCs in general, and Nepal in particular. This study aims to make a contribution to-wards this, with an analysis of the case of Nepal using the life cycle perspective.

This thesis uses three pillars of sustainable development to analyse sugarcane-molasses based bioethanol (MOE) production in Nepal. Sustainability criteria and life cycle assessment (LCA) provide the methodological framework for the study. It is the first of its kind in LDCs and assesses the sustainability criteria of bioethanol in the case of Nepal. The study provides useful information for decision makers, private investors, and other associated stakeholders, inter-ested in developing ethanol production in Nepal. The example of

Page 17: Dissertation on Sugar Production in Nepal

5

Nepal also serves the purpose of motivating the assessment of ethanol production potential in other LDCs.

1 . 2 T h e s i s o b j e c t i v e

The main objective of this thesis is to investigate the net energy balance, GHG emissions of bioethanol from a life cycle perspec-tive, and prospects for sustainable development in Nepal. The ob-jective has been achieved in the following steps:

1. Estimation of the net energy balance in the production of sugarcane-molasses-based bioethanol (MOE)

2. Examination of greenhouse gas (GHG) balances in the production and use of bioethanol

3. Evaluation of bioethanol production for the purposes of sustainable development

1 . 3 R e s e a r c h q u e s t i o n s a n d h y p o t h e s e s

The following research questions have been asked in the thesis:

Is bioethanol energy efficient; how much energy does it take to produce one liter of bioethanol?

How many greenhouse gas (GHG) emissions and sav-ings occur in the production and use of bioethanol?

What are the direct benefits of bioethanol substitution in the transport sector?

The first and second questions are life cycle assessment (LCA) re-lated questions, and the third is concerned with the immediate benefits, and sustainability issues observed from the production and use of bioethanol in the transport sector. Addressing these questions, this study performs a sustainability assessment of the production and use of bioethanol in Nepal. The answers to these questions provide valuable insights into the production of molas-ses-based ethanol in the least developed countries (LDCs) with re-spect to energy security, climate change mitigation, and sustainable development.

As per the research questions above, and based on reviews of pre-vious literature on bioethanol conversion technologies, life cycle

Page 18: Dissertation on Sugar Production in Nepal

6

assessment and aspects of sustainability, the following hypotheses have been tested:

The production of bioethanol requires a small amount of fossil fuel compared to its energy content.

Life cycle greenhouse gas (GHG) emissions from bioetha-nol are lower than conventional gasoline.

Bioethanol contributes to improved socio-economic and environmental performance, and can be promoted in Ne-pal in order to achieve sustainable development.

1 . 4 S c o p e a n d l i m i t a t i o n s

This thesis considers the full energy life cycle, material/waste flows, and carbon (GHG) flows involved in producing anhydrous ethanol (EtOH) from sugarcane molasses in Nepal. The system boundary covers local agricultural practices, the harvesting of sug-arcane, cane milling, the ethanol conversion phase, through the fermentation, distillation and dehydration route, and waste man-agement. Figure 1 provides a simplified schematic diagram of the sugarcane energy system in Nepal. Data sources relating to materi-al, energy, and waste flows have been taken from an intensive field study visit made to one of the established sugar factories in Nepal – Sri Ram Sugar Mills Pvt. Ltd. (SRSM). SRSM is the only factory which has installed a molasses-based ethanol conversion unit, and associated ancillaries such as wastewater treatment plants with bio-gas recovery. It is assumed that the factory operations for molas-ses-based ethanol conversion at SRSM are the best available in Nepal. Energy and greenhouse gas (GHG) balances have been es-timated from local inventory data for material and energy flows. The corresponding energy values and emission factors have been derived from regional and international studies.

Solar energy inputs have not been considered in the analysis of the net energy balance. Energy inputs and GHG emissions from hu-man labour have been considered. Energy generation and GHG emissions avoided by the commercial utilization of cane trash / waste have not been taken into account. In addition, energy inputs and corresponding GHG emissions for raw materials (for industri-al installations), and oil/lubricants/chemicals (for factory opera-tions) have also been excluded from this thesis. Sensitivity analyses have been performed to scrutinize the impacts of the variation in

Page 19: Dissertation on Sugar Production in Nepal

mateincorin oth

Figur

The ivestowho certethe fo

1 . 5

This thesisand othe-atransworkcle asviouspects

Chapcussiings o

rial and enerporate the fher sugar/di

re 1: SimplNepal

intended auors, researchare interested efforts to

form of bioe

O r g a n

thesis is divs is presenteobjectives oart technoloport fuel, ar

ks, with regassessment (Ls research lis of biofuel p

pter 4 is theon of the firof the paper

ergy flows, future expanistillery indu

lified layout

udience of thhers, and othed and moti

owards the pethanol in th

n i z a t i o n

vided into fived in Figuref the study.

ogies in biore presentedard to sustaiLCA) are exiterature regproduction

main bodyrst paper onr concerning

7

and scenarionsion of moustries in Ne

t of sugarc

his thesis arher stakehoivated enougproduction ohe least deve

o f t h e

ve chapters.e 2. Chapter In Chapterfuel produc

d. Methodolinability assexplained in garding LCAhave also be

y of the thesn ‘net energyg life cycle ‘g

os have beeolasses-basedepal.

cane bioene

re policy maolders (e.g. dgh to considof commerceloped count

s t u d y

The layout r 1 deals wir 2, an overvction, and blogical concessment critChapter 3. R

A, and the seen carried o

sis which bey balances’. greenhouse

en developed ethanol pl

ergy system

akers, privatedonor agencder making cial bioenergtries (LDCs)

and flow ofith the ratioview of statebioethanol epts and frateria and lifeReviews of sustainabilityout.

egins with a The major fgas (GHG)

d to lants

ms in

e in-cies), con-gy in ).

f the onale e-of-as a ame-e cy-pre-

y as-

dis-find-bal-

Page 20: Dissertation on Sugar Production in Nepal

ancesductisubstopmedatestion ithosesentstowa

Figur

s’ are also dion and the titution in Nent and clims the generalin Nepal. Fie from a sms concludingrds a PhD.

re 2: Layout

discussed. Sufindings of

Nepal - Oppmate changel prospects inally, the re

mall number g remarks an

t of the thesi

8

ustainability the paper ‘E

portunity to mitigation’

for sustainabesults are preof internationd indicates

is

aspects ofEthanol prod

promote suare explain

ability in bioesented andonal studiess the next s

bioethanol duction andustainable dened, which eethanol pro

d compared . Chapter 5 teps in rese

pro-fuel

evel-luci-duc-with pre-arch

Page 21: Dissertation on Sugar Production in Nepal

9

2 Sta te -of -a r t t echno log ies in b ioe thano l p roduc t ion and u t i l i za t ion

2 . 1 B i o f u e l s – a n o v e r v i e w

Bioenergy is obtained from biomass, in the form of different solid, liquid or gaseous fuels. Food crops (sugarcane, corn, soybean, wheat, and sugar beet), hydrocarbon-rich plants, wastes (crop, food, and municipal), weeds and wild growths, and lignocellulosic biomass are the potential sources of biomass for bioenergy genera-tion (Abbasi and Abbasi, 2010). Biodiesel is obtained through the esterification of plant oils, whereas bioethanol is mainly derived from agricultural feedstocks. The use of biofuels in the transport and industrial sectors tends to be on the increase due to growing concerns about fossil-fuel reserves, climate change and sustainable development. Liquid biofuels, namely biodiesel and bioethanol, are used in their pure or blended form (with conventional gasoline or diesel) in automobiles.

Biofuels from biomass are obtained primarily through two produc-tion processes: bio-chemical and thermo-chemical; bio-chemical processes may be further broken down into chemical and biologi-cal conversion technologies (Abbasi and Abbasi, 2010; Sheehan, 2009; Walter and Ensinas, 2010). With the thermo-chemical route, biomass is heated in the absence (or regulated/controlled concen-tration) of oxygen, which includes pyrolysis, gasification, and Fish-er-Tropsch processes. The Bio-chemical route consists of five al-ternatives - fermentation, esterification, anaerobic digestion, pho-tosynthetic organisms, and dark fermentation (Abbasi and Abbasi, 2010). Fermentation and esterification produce bioethanol and bi-odiesel respectively whilst anaerobic digestion creates biogas. Pho-tosynthetic organisms and dark fermentation are part of the exper-imental phase.

Fermentation and anaerobic digestion are classified as biological processes, whereas trans-esterification and hydro-treating follow chemical processes, in terms of bioenergy conversion technologies,

Page 22: Dissertation on Sugar Production in Nepal

as shcess ibiomlise tmainsion, fossil

Figur

Biofuon fstudi(IEALin, are wstarchreals,nol, palmHow

hown in Figuis that it con

mass into biothe polysacc

ntenance cosand these p

l fuel along

re 3: The prosources(IncludeAdopted

uels are broafeedstock cies provide

A, 2005; Roy2009; Naik

well establishes and the , grains and while oilsee

m and jatropwever, first g

ure 3. The anverts almooenergy, whcharide consts are quiteprocesses uthe product

oduction ofs s first, second

d from Sheeha

adly dividedharacteristicreviews of

yal Society, 2et al., 2010)hed, and intrans-esterisugar crops

ed crops supha can be cgeneration b

10

advantage ost all of the

hereas bio-chntent of thee high in thsually consu

tion chain (A

f biofuels fro

and third genn (2009)

d into severacs and prof biofuels t2008; Nigam). First gene

nclude the ffication of p

s can be fermuch as sunfconverted to

biofuels are

f the thermorganic comhemical pro

e biomass. he thermo-chume significAbbasi and A

om different

neration biofue

al categoriesduction patechnologie

m and Singheration biofufermentationplant oils. Fmented to pflower, rapeo methyl esbeing debat

o-chemical mponents ofocesses only

Operation hemical concant amountAbbasi, 2010

t biomass

els)

s, dependingthways. Sevs used glob

h, 2010; Yanuel technolon of sugars For exampleproduce bioee-seed, soybsters (biodieted due to

pro-f the

y uti-and

nver-ts of 0).

g up-veral bally and

ogies and

e, ce-etha-bean, esel). con-

Page 23: Dissertation on Sugar Production in Nepal

11

cerns over land use, food security/prices, water scarcity, and de-forestation. Second generation biofuel conversion technologies are complex, expensive and at an early stage of research & develop-ment and commercialization. They are obtained from, among oth-er things, lignocellulose (cellulose, hemicelluloses, and lignin – e.g. woodchips, straw and, cane bagasse) and feedstocks, through a conversion route which includes acid hydrolysis, followed by en-zymatic fermentation.

Second generation biofuels, produced from agricultural and forest-ry residues, municipal solid waste, and other forms of lignocellulo-sic biomass, can improve energy security, and reduce urban air pol-lution (Wyman, 1994) in spite of increased concerns about changes in land use patterns (Brennan and Ownede, 2010). Third genera-tion biofuels, derived from microalgae, could avoid land use changes since they can be grown in aquatic media i.e. water-surfaces (Brennan and Ownede, 2010; Goh and Lee, 2010). New research has been initiated in the development of genetically modi-fied crops/plants, and novel biofuels from non-food oil crops.

At present, commercial biofuels are mainly derived from energy crops (e.g. sugarcane, corn) and oil feedstocks (e.g. palm oil, oilseed rape). The production of biofuels has increased significant-ly in the past decade (GRFA, 2009). The reduction of greenhouse gas (GHG) emissions, achieving CO2 targets, the diversification away from commercial energy systems, favourable government policy and rural development are a few motivating factors in terms of encouraging biofuel production. Furthermore, biofuels can help to ensure energy security, reduce the environmental impacts arising from the transport sector, and create a conducive environment for economic growth in rural areas and the industrial sector at large. Nigam and Singh (2010) have highlighted energy security, econom-ic stability and environmental gains as the main advantages of us-ing biofuels. The key drivers of biofuel development in Asia are: (a) the security of the energy supply chain, (b) climate change, (c) land use changes and food security, and (d) rural development and poverty alleviation (Yan and Lin, 2009). Zhou and Thomson (2009) have also mentioned energy security, trade balances, foreign exchange, reduction in government expenditure, new markets for the principal agricultural products, employment in the agricultural sector, and climate change as being the driving forces, while defor-estation, problems with water security, the sdanger of monocul-

Page 24: Dissertation on Sugar Production in Nepal

12

ture, biofuels and food prices are highlighted as some of the nega-tive impacts of biofuels production in Asia. Escobar et al., (2009) have assessed issues relating to environment, technology and the food security of biofuels. Debates surrounding the production of biofuel using the same raw materials for both fuel and food pro-duction, and changing land use patterns have encouraged the as-sessment of the sustainability of biofuels.

2 . 2 B i o e t h a n o l p r o d u c t i o n

Bioethanol contributes more than 90% of the total liquid biofuel consumption in the world (IEA, 2007). Figure 4 shows different routes for the bioethanol production process. As can be seen in the figure, sugar/starch obtained from sugarcane/corn or cellulose feedstocks follows the process of fermentation, distillation, and dehydration in order to produce first and second generation etha-nol respectively. It should be noted that molasses (also a sugar-based product) is treated separately in the figure in order to make it distinct from other conversion routes. This thesis covers molas-ses-based bioethanol. First generation bioethanol, obtained from sugarcane and corn feedstocks has so far dominated the bioetha-nol market globally and other technologies are at an early stage of development. In 2009, global ethanol production was about 74 billion liters, a four-fold increase since 2000 and it has contributed to a reduction in GHG emissions by 87.6 million tonnes in a year (RFA, 2010). The United States (US) was the world largest pro-ducer of bioethanol, accounting for about 52% (i.e. 38.5 billion li-ters) of the total bioethanol production in 2009. Brazil was the largest bioethanol exporter and second largest producer with a share of 34% (25 billion liters). The EU produced 3.9 billion liters (5.3%) whereas two emerging developing countries, China and In-dia, contributed 2.8% and 0.5% of the total bioethanol production respectively. Bioethanol production could surpass 125 million liters by 2020 with the development of new agricultural poli-cies/programs along with the exploration of new feedstocks in America, Asia and Europe (Balat and Balat, 2009). The primary feedstocks for bioethanol production are corn (US), sugarcane (Brazil, Thailand, India, Australia), and beet/grain (EU). Different bioethanol production processes are discussed by various authors in the literature (Kumar et al., 2010, Abbasi and Abbasi, 2010; Najafi et al., 2009; Nigam and Singh, 2010; Cardona and Sanchez,

Page 25: Dissertation on Sugar Production in Nepal

2007mostlearn2004for in

Figur

Besidotherprodumolabioet2009veira% byzatiopointsiderjan e

; IEA, 2005t cost comp

ning curve in4; Bake et al.nternational

re 4: ProducAdoptedcane by-by Abbas

des producinr developingucing bioeth

asses. Few sthanol (Ngu; Prakash et, 2009). Moly weight, w/n and centrt when the eed to be thet al., 2009).

5). Ethanol etitive over n the produ, 2009), anddevelopmen

ction routes d from Penningproducts (mosi and Abbasi

ng bioethang countries hanol using studies haveuyen and Gt al., 1998; Klasses (with

/w) is the byrifugation prextraction oe cheapest sPakistan co

13

from sugarthe last few

uction of etd there is a stnt (Hira, 20

of bioethangton (2009) wilasses and bag(2010)

nol from susuch as Ththe by-prod

e been condGheewala, 2Kumar et ala fermentaby-product obrocess in th

of sugar is nosource of biould produce

rcane has prw decades, fothanol (Goltrong global10).

nol ith the inclusiogasse, which i

ugarcane juichailand andduct of the ducted into 2008a, b, c;l., 2010; Khble sugar conbtained duri

he productioo longer poioethanol pre 500 millio

roven to beollowing a sldemberg etl ethanol ma

on of sugar-is also cited

ce, as in Brd India are

sugar indusmolasses-b

; Harijan etatiwada andntent of 40 ing the cryson of sugar ssible. It is

roduction (Hon liters bioe

e the steep t al., arket

razil, also

stry– ased t al., d Sil-– 45 talli-at a

con-Hari-etha-

Page 26: Dissertation on Sugar Production in Nepal

14

nol from molasses which could be used in the transport sector in a blending ratio of 5 – 10%, saving US $ 200 – 400 million per year, bringing various environmental and health benefits (Harijan et al., 2009). Mozambique could extract 68 million liters of bioethanol from sugarcane by 2010 (Batidzirai et al., 2006). Nepal also has a sugar-molasses bioethanol production potential of 18 million liters per year (Silveira and Khatiwada, 2010). India could produce an abundant amount of bioethanol from its available molasses (Ku-mar et al., 2010). However, policy needs to be focussed on the de-velopment and use of bioethanol in order to realise such potential (Pohit et al., 2009).

In recent years, there have been a number of concerns with regard to the environmental, social and economic sustainability of bioeth-anol production. This thesis deals with the sustainability aspects of molasses-based bioethanol in the case of a sugar-producing least developed country, Nepal. Chapter 3 provides more details about the sustainability issues related to bioethanol production.

2 . 3 B i o e t h a n o l a s a t r a n s p o r t f u e l

Bioethanol is the most commonly used liquid biofuel in the trans-portation sector, especially in Brazil and the US, and its global use is growing quickly due to increased interest in both developed and developing countries. Pharmaceutical, cosmetic and beverage items are also obtained from the use of bioethanol. Thus bioethanol is not limited to the transport sector (EUBIA, 2005). However, the largest share of bioethanol (more than 80%) has been used to fuel automobiles and it is expected to represent a 4% share of the world’s motor gasoline consumption in 2010 and 6% in 2020 (IEA, 2005).

Vehicles can be fuelled either by pure or neat hydrous bioethanol (i.e. 95% ethanol v/v) or by a blend of gasoline and anhydrous (i.e. 99.5% v/v) ethanol – the most common blend ranges from 5 – 25% (Costa et al., 2010). It has been found that bioethanol as a fuel additive improves engine performance and reduces exhaust emissions in addition to increasing braking power and thermal and volumetric efficiency (Al-Hasan, 2003). Niven (2005) has exam-ined five important environment impacts of the ethanol enrich-ment of unleaded gasoline, viz. air pollution, subsurface contami-

Page 27: Dissertation on Sugar Production in Nepal

15

nations, greenhouse emissions, energy efficiency, and sustainabil-ity. Automobiles with 5 – 10 % ethanol blended fuels do not re-quire any engine adjustments or modifications while minor modifi-cations are needed for a 10 – 25 % ethanol blend (IEA, 2005).

Rising international oil prices, limited fossil-fuel reserves, envi-ronmental and climate change concerns, energy security, and di-versity of energy sources are the major driving forces behind the desire for developed countries to produce biofuels. Biofuels may also help to save foreign currency, improve access to commercial energy, and generate local employment. However, the biofuel agenda has not yet had any major impacts in the least developed countries (LDCs). One important reason is that development do-nors have not prioritized bioethanol production. In addition, proper government policies are still lacking, even though the po-tential for bioethanol production is high.

At the same time, there is increased apprehension about energy se-curity and climate change in both developing and developed coun-tries. Biofuels could contribute towards the mitigation of green-house gas emissions while also promoting development. Energy security concerns and climate threats for the least developed and land-locked countries are extremely high since they are too weak economically to invest in new domestic technologies, require agri-cultural land for a growing population, in order to produce food, and cannot afford imported fossil fuels. This study is an attempt to assess the sustainability of bioethanol in the case of a land-locked, least developed country, Nepal. The study not only highlights the potential which exists, but also the opportunities to enhance the potential further and actually contribute to addressing a large number of national and global questions simultaneously.

Page 28: Dissertation on Sugar Production in Nepal

16

3 Sus ta inab i l i t y c r i t e r i a and l i f e cyc l e a s sessment – conce pts and f rameworks

3 . 1 O v e r v i e w

In this chapter, the concept of sustainable development, sustaina-bility criteria, and life cycle assessment (LCA) are defined. Sustain-ability aspects of biofuels are presented and relevant criteria are developed for assessing bioethanol production, based on literature reviews, and existing local conditions. Issues related to the integra-tion of sustainability and LCA are also discussed. The life cycle as-sessment (LCA) tool is used to address the sustainable develop-ment of biofuels. Indeed, a life cycle based system approach serves an important role in addressing the economic, social and environ-mental integrity of any production system. This thesis uses a LCA methodology to evaluate the net energy and greenhouse gas (GHG) balances of molasses-based bioethanol (MOE) from cradle to grave. The case of Nepal, in terms of the production of bioethanol from sugarcane-molasses is realized and explained. Other general aspects of sustainability, such as the economy, local air pollution, and hard currency savings are also dealt with.

3 . 2 D e f i n i n g s u s t a i n a b l e d e v e l o p m e n t a n d s u s t a i n a b i l i t y

In general terms, sustainability covers the realms of environment (planet), society (people), and economy (prosperity). By sustainable development, we actually mean that the environment, comprising the earth and its ecosystems, biodiversity, scarce resources and cul-tures, needs to be sustained, while people (survival, life expectancy, education, equity and equality), economy (wealth distribution, con-sumption), and society (institutions, social capital, states, regions) need to be developed (Kates et al., 2005)

Page 29: Dissertation on Sugar Production in Nepal

17

The concept of sustainable development and its underlying three pillars of sustainability have become important in dealing with the prosperity of developing and least developed countries (LDCs). In finding indicators for sustainable energy systems, the current state, economic and social systems, driving forces, and the responses of the institutional set up should be dealt with, and their interconnec-tion considered, in order to determine the current situation regard-ing the sustainability of the energy system as shown in Figure 5. Economic prosperity, social development and environmental in-tegrity are well connected and involve trade-offs between their varying objectives. Thus it is very difficult to deal with these fac-tors in isolation. The three pillars always reinforce each other (He-diger, 2000). For instance, environmental pollution always involves economic costs/activities. Poverty, equality and social justice are also intertwined. Moreover, institutional strengthening i.e. net-working, collaboration and cooperation between stakeholders, and political stability are also vital in order to enable sustainable devel-opment in developing and least developed countries (LDCs). Sus-tainable development aims to keep the integrity of the overall sys-tem. Economic sustainability includes investment, benefits and the availability and mobility of scarce national resources. Environmen-tal sustainability is the ability of the natural environment to sustain human life. Social sustainability covers issues of equity and justice in wealth distribution, for example job creation, and human rights. Likewise, sustainable development of the bioenergy (biofuels) sys-tem is also very significant in terms of creating economic prosperi-ty, and putting in place social and environmental safeguards.

Energy security, rural development, and the climate change agenda motivate the production and utilization of biofuels derived from energy crops. Sustainability criteria are needed to justify the appro-priateness of these energy systems. Interaction between the three pillars of sustainable development are crucial, as well as being complex and multidimensional throughout the production chain, which includes types of feedstock, land use, conversion technolo-gies, material and energy flows, pollution, and geographical condi-tions.

Page 30: Dissertation on Sugar Production in Nepal

Figur

Thermentticulasustaconsu(e.g. sessinZhounomisociaprovematedevelhas pproduand tperitydevelergy form

re 5: The thtion in Adopte

re is a vast t of energy sar (Afgan et ainability indumption), ejobs), and

ng the sustau and Thomics (trade ba

al dimensionement in fa change andlopment of

proposed sixuction, viz. the local appy, social welloped a sustsystems in

mance, and so

hree pillars othe sustainad from IAEA,

amount ofsystems in gal., 2000; C

dicators, vizenvironmenteconomic (eainability of

mson (2009)alance, pricens (increasearmers’ incod air quality)f biodiesel ax criteria on greenhouse

plications ofll-being, andtainability frterms of e

ocial accepta

18

of sustainabiable energy s, Fact Sheets

literature oeneral and t

Cramer, 2006z. resource t (e.g. emisse.g. investmf energy sys have found

e of petroleued jobs in tome), and e are the mai

and bioethanthe theme o

e gas emissiof biomass, bd environmeramework foeconomic viability.

ility and thesystem

on the sustathe bioenerg6; Elghali et(e.g. fossil sions and p

ment, cost) astems (Afgad that energum, an imprthe agricultuenvironmentin driving fonol in Asia.of sustainabions, compet

biodiversity, ent. Elghali or the assessiability, env

eir interac-

ainability assgy system in t al., 2007). Ffuel and en

pollution), soare used foran et al., 20gy security, oved econoural sector, tal impacts orces behind Cramer (2ility for biomtition with feconomic pet al. (2007)sment of bi

vironmental

sess-par-

Four nergy ocial r as-000). eco-my), im-(cli-

d the 006) mass food pros-) has oen-per-

Page 31: Dissertation on Sugar Production in Nepal

19

Smeets et al. (2006) have assessed sustainability criteria viz. The ecological, economic and social impacts of sugarcane-based etha-nol production in Brazil, compared using the Dutch sustainability criteria. GHG balances, competition with food & energy supply, biodiversity, wealth, welfare and the environment were used as de-termining criteria. These criteria might also be useful to establish a product certification system for the international market. Envi-ronmental or ecological impacts cover water use, water pollution, land use, forest protection and biodiversity, soil erosion, green-house gas emissions and energy balance. On the other hand, socio-economic criteria might include competition with food production, number of jobs, income distribution and land tenure, wages, work-er rights, child labour, social responsibility and benefits (Smeets et al., 2006).

Goldemberg et al. (2008) have discussed the sustainability of etha-nol production from sugarcane, considering air quality improve-ment, rural development, biodiversity, deforestation, soil degrada-tion, water source contamination, food vs. fuel production, and la-bour conditions in the fields. They have also discussed sustainabil-ity aspects of ethanol production, namely environmental and social factors, along with the following sustainability criteria, as suggested by the Cramer commission (Cramer et al., 2006): (a) energy bal-ance, (b) environment aspects, such as gaseous emissions from sugarcane and ethanol production, or due to sugarcane burning), water (water availability, water pollution - organic pollutants, inor-ganic pollutants), land use (expansion of sugarcane, land competi-tion - ethanol versus food crops), soil, biodiversity; (c) social as-pects and social impacts such as labour conditions, jobs creation, wages and income distribution, land ownership, working condi-tions. Zhou et al. (2007) have selected four sustainability indicators for assessing biofuels - economics, environment, energy, and re-newability. The energy indicator represents how much energy is required to produce biofuel and renewability is evaluated using the rate of exploitation of natural resources, such as fuel-wood.

In this way, there is great concern over the sustainability of biofuel in both developed and developing countries. For the Least devel-oped countries (LDCs), whose main primary energy source is tra-ditional biomass, issues of sustainability are quite high on the agenda, since rural populations live in conditions of utter poverty and do not have enough resources for economic growth.

Page 32: Dissertation on Sugar Production in Nepal

20

3 . 3 D e f i n i n g l i f e c y c l e a s s e s s m e n t ( L C A )

Life cycle assessment (LCA) is a concept used to evaluate the envi-ronmental performance of a product or service during its entire life span. LCA is an holistic systems approach and takes into ac-count the inputs and outputs of the entire production system, viz. raw materials, energy and waste, at every stage, from resource ex-traction (raw materials acquisition) to the final utilization and dis-posal of the product. LCA has become important since it encom-passes all the processes and environmental discharges during the production phases of the product, thus avoiding the shift of envi-ronmental problems from one place to another along the produc-tion chain (USEPA, 2006). The results of LCA have increasingly been used as a decision-making policy tool for the selection of products, and for environmentally friendly product-certification.

Rebitzer et al. (2004) and Pennington et al. (2004) have elaborated on LCA application and practices. ISO 14040 - standards/series (ISO, 2006a and 2006b) also uses the LCA concept and methodol-ogies. LCA comprises four phases: goal and scope definition, in-ventory analysis, impact assessment, and interpretation (see Figure 6a). Goal definition and scoping describe the objectives of the analysis, the production processes and system boundaries. The purpose of the study is measured as a functional unit. In the inven-tory analysis, the material inputs/outputs are identified and quanti-fied, for example, natural resources (energy, land, water etc.) and environmental releases (e.g. emissions or wastes). Human and eco-logical effects that occur due to resource usage/consumption or emissions/waste released into the air, water or soil are taken into account in the impact assessment. This phase reveals the contri-bution made by different impact categories, for example: resource depletion, climate change, eco-toxicity, human and ecological health, acidification, and eutrophication. Following the inventory analysis and the impact assessment, the interpretation of the LCA is ultimately carried out to select the product or service based on the envisaged environmental performance and in order to comply with the objectives of the study. Thus, LCA provides a compre-hensive environmental overview of the product, from cradle to grave.

Page 33: Dissertation on Sugar Production in Nepal

21

There are lots of applications of the LCA concept in evaluating re-newable and sustainable energy systems. The LCA concept and methodologies have been widely applied in developing bioenergy systems. Liquid biofuels are increasingly seen as potential substi-tutes for gasoline and diesel in transportation. It is, therefore, im-portant to assess the environmental performance of biofuel pro-duction and consumption, and also to compare them with conven-tional fossil fuels. Several LCA studies and reviews have been con-ducted to investigate the impacts of the life cycle resource con-sumption and environmental burden of bioethanol production from different feedstocks, and they are primarily focused on the life cycle net energy balance and GHG balances (see, for example, Shapouri et al., 2004; Macedo et al., 2008; Dai et al., 2006; Nguyen et al., 2007a/b/c, 2010; Blottnitz and Curran, 2007; Gnansounou et al., 2009; Cherubini et al., 2009; Hoefnagels et al., 2010; Xunmin et al., 2009). In this thesis, the life cycle energy and greenhouse gas (GHG) balances have been investigated for molas-ses-based bioethanol (MOE). Molasses are a low-value by-product resulting from sugar production. The definition of system bounda-ries, local sugarcane growing practices, harvesting, factory opera-tions and waste management, and allocation methods in LCA are some of the key features of the sustainability assessment of bioeth-anol carried out for Nepal.

3 . 4 I n t e g r a t i n g s u s t a i n a b i l i t y a n d L C A

LCA conventionally covers environmental sustainability, but ef-forts have been made to extend the concept to cover the three pil-lars of sustainability, including economic prosperity and social in-tegrity. The future of LCA is likely to encompass all aspects of sus-tainable development, and the life cycle costing will provide policy decision-makers with information on investment and return, while social aspects might include indicators of millennium develop-ment goals (MDGs) in a holistic approach (Hunkeler and Rebitzer, 2005). LCA analyses have been carried out for the sustainability assessment of various products/services during the last decade. For example, Heller et al., (2000) have scrutinized economic, social and environmental dimensions of the US food system, taking into account the interaction between LCA and sustainability through-out the life cycle. Zhou et al. (2007) have analysed single- and mul-

Page 34: Dissertation on Sugar Production in Nepal

ti-dimassesbility

Fig.6

Figur

The sustasis anappliity asand cmenthensitainabtainabis opFigurtem csecurand C

mension susssment of fuy indicators a

6(a)Life cycle(LCA) frAdopted f

re 6: Integra

conceptual ainability assnd assessmeied to bioethssessment isconsumptiot. Sustainabiive approacbility criterible developm

ptimized forre 6b. Linkacan also be re the best, Clift, 1999).

stainablity asuels in the liand sustaina

e assessmenramework from ISO (200ation of LCA

framework sessment incent optimizahanol produs to evaluatn in relationility assessm

ch, and the a in detail. Iment has ber further image or integoptimized wmost envirIn this way

22

ssessment cife cycle fraability indexe

t

06)

Fig.6(

A and sustai

and basic cludes relevaation (DETEuction. The me and optimn to the targment is also

relevance aImpact analeen achieved

mprovement.gration seemwith the helronmentally

y, there is a c

criteria for thamework, ines.

(b) Sustainabprocedur

Adopted frinability asse

methodologance analysiEC, 2004). Tmain aim ofmize bioethagets of susta a systemat

analysis detelysis evaluatd or not. Fin These step

ms importanlp of object

y benign opclose link be

he sustainabcluding rene

bility assessmre rom DETEC (essment

gy guidelineis, impact anThis can alsf the sustainanol producainable devetic and comermines the tes whether nally, the sysps are shownt when the tive functionptions (Azapetween life c

bility ewa-

ment

(2004)

e for naly-o be abil-

ction elop-

mpre-sus-sus-

stem wn in

sys-ns to pagic cycle

Page 35: Dissertation on Sugar Production in Nepal

23

assessment and sustainability assessment of biofuel production (see Figure 6). Moreover, Zah et al., (2009) have recently outlined an idea for the standardization and simplification of life cycle as-sessment, as a driver for more sustainable biofuels, using a web-based sustainability check-list for benchmarking sustainability cri-teria. This should help developing countries conduct LCAs of bio-fuels when product-certification schemes become mandatory.

3 . 5 D e v e l o p m e n t o f s u s t a i n a b i l i t y c r i t e r i a f o r b i o e t h a n o l p r o d u c t i o n

The literature has been reviewed to find out more about the sus-tainability indicators of bioethanol production. Yan and Lin (2009) have mentioned energy security, climate change, rural development and poverty alleviation as the driving forces of sustainable biofuel production. The energy and food security debate is crucial when discussing the sustainability assessment of bioethanol since agricul-tural land is used to produce feedstocks, and these same feedstocks can alternatively be used for food production, such as sugarcane and corn. Biofuel and food prices have become an important fac-tor in Asia when considering biofuel production, due to their con-flicting nature, in terms of price, which could subsequently lead to political instability (Zhou and Thomson, 2009). Sheehan (2009) has mentioned that LCA is used for assessing the sustainability of biofuels not only when it comes to net energy balance or the car-bon footprint, but also expanding it to include global land and wa-ter resources, global ecosystems, air quality, public health and so-cial justice. As he has shown, analytical frameworks for LCA and sustainability assessment for biofuel have received increased atten-tion in recent years. Research on the topic 'biofuels and sustaina-bility' and 'ethanol and life cycle' have increased six-fold and three-fold respectively from 2006 to 2008 (Sheehan, 2009). Smeets et al. (2008) have evaluated the environmental and socio-economic im-pacts of the production of ethanol from sugarcane in the state of Brazil for the purposes of product certification. Phalan (2009) has given an overview of the social and environmental costs and bene-fits of biofuels in Asia, and the major factors identified were land use, feedstocks used, technology issues and scale. According to Schubert and Blasch (2010), bioenergy can only play an important role in greenhouse gas (GHG) reduction when it is produced in a

Page 36: Dissertation on Sugar Production in Nepal

24

sustainable way, thus the biofuel-pathways with minimum envi-ronmental and socio-economic problems should be promoted. In-itial subsidies could also be instrumental in promoting environ-mentally benign biofuel promotion processes. Government poli-cies, such as mandatory blending targets, tax exemptions and sub-sidies are the driving forces for biofuels production in many coun-tries (Sorda et al., 2010). The development and selection of the sustainability criteria for bioenergy depends on feedstock charac-teristics and different production pathways. Buchholz et al. (2009) have also screened 35 sustainability criteria from a survey of ex-perts, which are grouped into three pillars of sustainability. Regard-ing the experts’ views, which were based on attributes of relevance, practicality, reliability, and importance, only two criteria, namely energy balance and greenhouse gas balance, were found to be the most critical, and local social parameters such as compliance with laws, food security, participation, human rights and social cohesion were ranked lower down. Competition between food and bioener-gy production, and deforestation were two of the sustainability cri-teria used in the potential assessment of modern bioenergy sources in one of the least developed countries (LDCs) in Africa - Mozambique (Batidzirai et al., 2006)

3 . 5 . 1 I d e n t i f i c a t i o n o f s u s t a i n a b i l i t y i n d i c a t o r s f o r b i o e t h a n o l i n N e p a l

Within the context of the sustainability assessment criteria for bio-ethanol production in the least developed countries (LDCs) such as Nepal, the scarcity of commercial transport fuels, the flow of hard currency, with state-subsidies on the imports of petroleum, and local air pollution in urban cities are motivating factors for us-ing a blend of bioethanol in gasoline. Energy security and the di-versification of transport fuels, along with issues of food security (i.e. sugar), environmental problems, such as water pollution, and GHG emissions, play a vital role in the sustainability of bioethanol. Employment generation in sugarcane cultivation and industrial op-erations, and the use of domestic resources for economic growth at a local and regional level are to be assessed when evaluating the sustainability of bioethanol. The technical viability of bioethanol production is also important. Empowering local communities, strengthening institutions among the concerned stakeholders and

Page 37: Dissertation on Sugar Production in Nepal

25

political stability are all necessary for sustainable development of bioethanol in Nepal.

Thus there are many different and important criteria to be consid-ered in this context. This thesis focuses on some of the most im-portant sustainability criteria. An overview of the indicators identi-fied is presented in Table 1. The indicators marked with an asterisk (*) are the focus of the present study. Many of the other criteria have been discussed from a sustainability point of view, but more as a means of analysing and defining the problem, thus lacking the necessary depth for arriving at major conclusions.

Table 1: Selected sustainability criteria for evaluating the appro-priateness of bioethanol production and use in transport – the case of Nepal

Environmental

Fossil fuel substitution * Life cycle energy balances * CO2 emissions from fuel substitution in automobiles * Life cycle GHG balances * Local air pollution * Wastewater management * Change in land use pattern Soil pollution Utilization of natural resources Protecting forests (avoiding deforestation)

Economic

Investment (costs and benefits analysis) Savings on oil imports * Availability of resources (Capital) Industrial growth Agriculture growth Energy security and diversification * Improved trade balances Economic instruments: subsidies/tax exemptions Carbon trading (under CDM)

Social

Food vs. energy security * Employment generation, and wages Rural and local development Trade union, workers' facilities & safety Poverty reduction Equality, equity and cultural sovereignty

Others Institutional Technical Political

Page 38: Dissertation on Sugar Production in Nepal

26

Two important sustainability indicators: net energy and greenhouse gas (GHG) balances have been analysed in the life cycle frame-work. The economic and social factors of biofuel production, which play a key role in determining the sustainability of bioetha-nol production, are also discussed so as to justify the research questions and hypotheses of the thesis. However, this study is lim-ited to evaluating the direct economic and social benefits. The life cycle assessment of economic and social sustainability and the op-timization of relevant sustainability indicators could possibly be the scope of future analysis.

3 . 5 . 2 D e f i n i n g n e t e n e r g y a n d g r e e n h o u s e g a s ( G H G ) b a l a n c e s

Two important sustainability criteria – energy efficiency (net ener-gy balances) and greenhouse gas (GHG) balances have been de-fined along the entire product-chain. The actual net energy and GHG balances of bioethanol production in Nepal can then be es-timated.

a. Net energy balance

Energy balances primarily deal with the life cycle energy efficiency of bioethanol and the savings in non-renewable fossil fuels com-pared to bioethanol in the entire product-chain. There are defined terminologies for dealing with energy balances. The net energy value or balance (NEV or NEB) of bioethanol (EtOH) is the difference be-tween the energy content of the bioethanol produced and the total primary energy inputs (fossil plus renewable) in the entire fuel production cycle.

NEV = EF EI where, EF is the energy content (lower heating value) of ethanol, EI is the total amount of primary energy inputs

Net renewable energy value/balance (NREV) is calculated as fol-lows:

NREV = EF NEI where, NEI is the non-renewable energy or fossil fuel in-put.

Page 39: Dissertation on Sugar Production in Nepal

27

The energy yield ratio is defined as the ratio between the energy con-tent of bioethanol and the total fossil energy required to produce it.

energy yield ratio= energy content in ethanol

fossil energy input

NREV and the energy yield ratio provide essential information necessary to assess the contribution of biofuels to energy security. The threshold limit is NREV > 1, while NEV gives and analysis of the total input/output of energy, including renewable inputs. In this study, energy recovered from by-products within the system, i.e. excess bagasse and biogas are also incorporated into estimates of NEV, NREV, and energy yield ratio.

b. Greenhouse gas balances

Total net emissions of greenhouse gases (GHG) are estimated from greenhouse gas balances, including both release and absorp-tion through the life cycle. The main GHGs considered in the analysis are: carbon dioxide (CO2), methane (CH4), and nitrous ox-ide (N2O). The effect of these gases is measured using Global Warming Potential (GWP), expressed in CO2 – equivalent (CO2eq.). The estimation of GHG emissions is carried out by taking account of the direct consumption of fossil fuels, the production of ferti-lizers/chemicals, activities taking place on agricultural farm land, operations in industrial premises, and the ultimate combustion of fuels.

This thesis uses the life cycle assessment (LCA) methodology to evaluate greenhouse gas (GHG) balances and avoided emissions compared to conventional gasoline. Material and energy inputs, and their GHG emissions in sugarcane farming (fertilizer applica-tion and irrigation), transportation, milling, fermentation, distilla-tion and the dehydration processes are considered in the analysis. The system boundary covers local agricultural practices, the har-vesting of sugarcane, cane milling, the ethanol conversion phase (through the fermentation, distillation and dehydration route), and waste management.

The functional unit in LCA is a measure of quantified performance of products or services, and it enables comparison between the

Page 40: Dissertation on Sugar Production in Nepal

28

products / services under consideration. GHG emissions in terms of the kgCO2eq m-3 (also, in kgCO2eq MJ -1) functional unit are eval-uated without considering the mechanical efficiency of the end us-er of bioethanol as the transport fuel. Material and energy flows in the sugarcane bioenergy systems are normalized to this functional unit.

Avoided emissions in the production and combustion/use of bio-ethanol (as the gasoline substitute) are estimated using the follow-ing equation, considering energy equivalencies of gasoline and bio-ethanol i.e. 1 GJ of bioethanol replaces 1 GJ of gasoline.

Avoided life cycle GHG emissions %

= GHG emissions in gasoline - GHG emissions in bioethanol

GHG emissions in gasolinex 100

3 . 5 . 3 R e a l i z a t i o n o f a c a s e s t u d y – s e n s i t i v i t y a n a l y s i s a n d d e v e l o p m e n t o f s c e n a r i o s

Sugarcane is one of Nepal’s cash crops, and 2.6 million tonnes of sugarcane was produced from 64 thousand hectares of land, giving an average yield of 40.6 tonnes per hectare in 2006/07. The trend has been towards an increase in production, cultivation area, and productivity since 1999/00. Nine sugar mills are operational with a total installed capacity of 17,050 cane-tonnes per day, and are lo-cated in different districts of the fertile plain land of the South. The sugar industry produces low-value molasses (4 - 5% of the cane-stalk, w/w) as a by-product, which can be used for bioetha-nol production. At present, an ethanol plant with a production ca-pacity of 30 m3 per day has been installed to produce molasses-based ethanol at Sri Ram Sugar Mills Pvt. Ltd. (SRSM).

In order to evaluate sustainability aspects of bioethanol production in Nepal, a field case study was carried out at SRSM. Field data based on material, energy, and waste flows (inputs and outputs) in both agricultural practices and industrial operations are considered. Figure 7 provides details of energy and material flows, including emissions and waste at each stage along the ethanol production chain in Nepal.

There are actually two main by-products in the sugar milling pro-cess: molasses and bagasse. Bagasse is used as the fuel input to

Page 41: Dissertation on Sugar Production in Nepal

29

boilers. The steam from bagasse-fired boilers is used in power tur-bines to generate electricity, and the exhaust steam is utilized as the heat required for the process of sugarcane milling, distillation and dehydration. Molasses are converted into anhydrous ethanol fuel (EtOH) via the route of hydrous ethanol (95% (v/v) ethanol, called rectified spirit). The fermentation of molasses and the sub-sequent process of repeated distillation generate rectified spirit. To produce anhydrous ethanol (99.5% v/v), rectified spirit (95% v/v) is passed through a typical molecular sieve dehydration col-umn/plant and following this the anhydrous vapour of EtOH are condensed and cooled down to produce the final bioethanol.

Distillery waste water effluent (spent wash) is treated prior to dis-posal since treatment is essential from an environmental point of view. An anaerobic effluent treatment plant generates biogas, which is later used as a fuel, which is input into the boilers. Ba-gasse, which is used to generate steam for electricity and the heat production, is considered as a source of renewable energy input in-to the system. Thus, bioethanol is only produced from low-value molasses in Nepal at this point. Sugar juice is mainly dedicated to the production of sugar.

In LCA, economic allocations are used to divide the resource con-sumption (primary energy), and environmental burdens (GHG emissions) in upstream operations when we get co-products (sugar and molasses). The market prices of sugar and molasses determine the division of energy consumption, and greenhouse gas (GHG) emissions between these two products. The average allocation ra-tio was found to be 22.2:1.

Figure 8 (a-j) shows actual field conditions in agricultural practices, transportation of feedstocks, and factory operations, including the generation of the co-products. SRSM is the only plant in Nepal which has an installed molasses-based ethanol conversion unit, and associated ancillaries such as wastewater treatment with biogas re-covery. Therefore, factory operations for molasses-based ethanol conversion in SRSM are considered to be the best available ethanol plant in Nepal.

In order to cover the effect of variations in input parameters, such as fertilizers, diesel consumption for irrigation, allocation ratio (i.e. the prices of co-products), and agricultural yields, sensitivity anal-

Page 42: Dissertation on Sugar Production in Nepal

30

yses have been performed for estimating both net energy and GHG balances. Scenarios have also been developed at the plant level to evaluate the consequences of adopting different wastewater treatment processes, with or without biogas recovery, and selling surplus bagasse electricity to the grid.

Page 43: Dissertation on Sugar Production in Nepal

Figuree 7: System bboundary ancane-bas

31

nd material fed systems i

flows (per hin Nepal

hectare) for s

sugar-

Page 44: Dissertation on Sugar Production in Nepal

b. Trato ttruc

c. Feethe

f. Cog(righ

nsportation: Dthe factory gateck (20%).

eding of feedstmilling proces

generation plaht) to generate

Different modee; they include

tock intoss

d. Ol

e. InLthatiosugathtai

nt: Bagasse-fire heat and elec

32

a. Sugarcane ing are donal inputs acides, and for irrigatifor sugarcaharvesting erage prodtare.

es of transporte animal-power

Open burningleaves)

dustrial comptd. (SRSM) runarvesting seasoons include sugar as the maisse as co-prode crushing of ined at the cry

red industrial ctricity required

plantation, grne by human lare fertilizers,diesel (to op

ion). The totaane growth is time lasts up

ductivity is 40.

t for carrying red cart (50%)

g of sugarcan

plex – Sri Ramns for about 5on of sugarcanugarcane millinin product, anducts. Bagassef sugarcane whystallization/ce

boilers (left), d for the plant

rowth, and halabour; main m pesticides, in

perate water pal duration req

11-12 monthto five month.61 tonnes pe

sugarcane feed), tractor (30%

e wastes (top

m Sugar Mills5 months durinne. Industrial ong, which prond molasses ane is separated dhile molasses entrifugal proc

and steam tut

arvest-materi-nsecti-pumps quired s, and s. Av-r hec-

dstock

%), and

ps and

s. Pvt. ng the opera-oduces nd ba-during is ob-ess.

rbines

Page 45: Dissertation on Sugar Production in Nepal

g. Ge7 –

i. DistDeApto

Figur

eneration of su– 9 % of the su

tillation plant ehydration plapprox. 120 tongenerate 30 m

re 8 (a – j): farming a

Photograp(SRSM), N

ugar: The yielugarcane crush

(left) – molasant (right) - mnnes of molas

m3 of ethanol inj

Realizationand factory

phs: Author’s Nepal

33

ld is hed.

h. Genof th35 –

sses based biomolasses based

ses (42% w/wn the distillatioj. Effluent (w

ment planttal load ocbiogas, whthe boilersthane) is ption. In thSRSM, 100Anaerobic rectly fed in

n of the caseoperationsfield visit at

neration of baghe milling pro– 37% of the c

oethanol (95%bioethanol (9

w - fermentablon plant.wastewater or t where reductccurs along withich is later uss. 0.53 Nm3 oproduced per he present stat0% biogas is Digestion Pro

into boilers.

e study in N

Sri Ram Sug

gasse: a co-process and the ycane crushed.

% v/v ethanol)99.5% v/v ethle sugar) is req

spent-wash) tion in environth the generatised as fuel inpof biogas (68%kg of COD r

te-of-the-art crecovered fromocess (ADP) a

Nepal: sugar

gar Mills Pvt

roduct yield is

), and hanol). quired

treat-nmen-ion of put in

% me-reduc-ase in m the nd di-

rcane

. Ltd.

Page 46: Dissertation on Sugar Production in Nepal

34

4 Resu l t s and Discuss ions

4 . 1 O v e r v i e w

In this chapter, the findings of the research and case study are dis-cussed. The results of the evaluation of the net energy balances, energy yield ratios, and GHG balances are presented for the case of Nepal. Sensitivity analyses are performed taking into account economic allocation, material inputs, energy consumption, and sugarcane yield. Different scenarios for the treatment of wastewater and the case of surplus electricity derived from bagasse are also dealt with for the purposes of evaluating GHG balances. Finally, important sustainability aspects of the production of mo-lasses-based bioethanol are discussed and summarized. The vari-ous steps taken in the calculations are explained in detail in the fol-lowing papers: Khatiwada and Silveira (2009), Khatiwada and Sil-veira (2010), and Silveira and Khatiwada (2010) which are annexed at the end of this thesis.

4 . 2 L i f e c y c l e n e t e n e r g y b a l a n c e s a n d t o t a l e n e r g y y i e l d r a t i o

In the case of sugarcane farming in Nepal, the primary energy con-sumption (per hectare) is 45,371.6 MJ (see, Table 2). The share of fossil fuel and renewable energy inputs are 67.5% and 32.5% re-spectively. Out of the fossil fuel inputs, diesel used for irrigation contributes 43.2% and fertilizers/chemicals comprise 45.7%. Since transportation is mainly carried out using animal-driven carts, it has only a small share, that is to say 5.9%, of total fossil fuel in-puts. In the factory operations, 737.3 tonnes of bagasse is generat-ed per day, which has a heating value (HHV) of 7,036.5 GJ. Ba-gasse and biogas supply energy for the plant’s processes. The sum of the primary energy requirements of the different processes gives the total energy demand.

Page 47: Dissertation on Sugar Production in Nepal

35

Table 2: Primary energy requirement of one hectare of sugar-cane farmland in Nepal (40.61 tonne/ha)

Activities Fossil fuel inputs (MJ/ha)

Renewable energy inputs (MJ/ha)

1. Sugarcane farming

Fertilizers

Phosphorous (P2O5) 382.1 - Potash (K2O) 387.8 - Nitrogen 7,883.7 -

Pesticides/Insecticides 4,761.4 - Herbicides 586.7 - Diesel (irrigation) 13,227.7 - Human Labor 1,625 14,723.5 2. Diesel (Transportation) 1,793.6 - Sub-total (fossil and re-newable) 30,648.1 14,723.5 Total 45,371.6 MJ/ha

Table 3 shows the primary energy balance in all the processes. The sugar milling process consumes a large amount of primary energy (73%). It should be noted that surplus bagasse amounts to 17%, and is also taken into account in the calculation.

To produce one liter of anhydrous bioethanol (99.5% EtOH or MOE), the life cycle energy input analysis shows that the renewa-ble energy contribution amounts to 91.7% (31.42 MJ/L) since most of the operations are run using bagasse, biogas and non-motorized transportation. The only exceptions are the application of fertilizers/chemicals and irrigation. Fermentation/distillation consumes 12.63 MJ/L, which is the most energy intensive part of the process, followed by sugar milling which consumes 10.46 MJ/L (see Figure 9).

Page 48: Dissertation on Sugar Production in Nepal

36

Table 3: Primary energy balance of sugar milling in Nepal (in-cluding distillation, dehydration and ETP)

Processes Sectors GJ/day

Primary energy required

Sugarcane milling Power (including elec-tricity to facilities) 990.3

Heat 4,600.0

Fermentation/Distillation Power 73.8

Heat 240.2

Dehydration Power 78.1

Heat 54

Effluent treatment plant (ETP) Power 32.8

Lighting in the distillation, dehydration, ETP plus electricity in their facilities

Power 54.5

Total primary energy required 6,123.7

Primary energy supply Bagasse primary energy input 7,036.5 ETP biogas input 319.3 Total primary energy input 7,355.8 Excess bagasse 1,232.1 % excess bagasse 16.75 %

Taking the energy content of anhydrous bioethanol (EtOH) to be 21.2 MJ/L, the net renewable energy value (NREV) is positive (18.36 MJ/L) but the net energy value (NEV) is negative ( 13.05 MJ/L). The higher positive value of NREV shows that the amount of fossils fuels used in the production cycle of bioethanol is quite low. In fact, the ratio between the energy content of bioethanol fuel to fossil fuel inputs (energy yield ratio) is 7.47. However, the neg-ative value of NEV shows that more energy is required to make EtOH than there is in its final energy content. In any case, low quality biomass feedstock, i.e. molasses (in terms of market and energy values), is converted into a high quality commercial energy carrier - bioethanol.

Page 49: Dissertation on Sugar Production in Nepal

Figur

4 . 2

Sensieconproce

(a) V

The molaof m50%,and econstrenew

re 9: The coto prodstage of

. 1 S e n sb a l a

itivity analysomic allocatess heat) on

Variation of a

price of moasses-based e

molasses will , 100%, 150energy yieldtant. It has wable energ

ontribution oduce 1 literf the ethano

s i t i v i t y aa n c e s )

ses are perfotion ratio, an the net ene

allocation ratio

olasses is quethanol incrrise. The pr% and 200%

d ratio, whilbeen found

gy value (NR

37

of fossil andr of EtOH ol production

a n a l y s i s

ormed to finnd (b) energ

ergy values a

o related to mo

uite low in reases, it canrice of mola

% to see thest the price

d that the neREV), and

d renewable (MOE) in

n chain

( n e t e n e r

nd out the gy consumpand energy y

olasses price

Nepal. As tn be expecteasses has bee effect on the of sugar iset energy vaenergy yield

energy requNepal, at

r g y

effect of (a)tion (power

yield ratio.

the demanded that the peen increasehe energy vas assumed toalue (NEV),d ratio also

uired each

) the and

d for price d by alues o be , net

o de-

Page 50: Dissertation on Sugar Production in Nepal

creasFor ereducrespoenerghighethe fu

Figur

se with an inexample, a ction of 90.2onding energy yield ratier value for fuel.

re 10 (a-c): ENEV, N

ncrease in th100% increa2% in the Nrgy values oio is also rethe energy y

Effect of chNREV, and

38

he price of mase in the p

NEV and 14.f (-24.83) M

educed to 3.yield ratio eq

anges in thethe energy y

molasses, seeprice of mol.7% in the N

MJ/L and 15.88 (a 48.8%quates to a

e price of moyield ratio

e Figure 10 (lasses leads NREV with 5.66 MJ/L. % reductionhigher meri

olasses on

(a-c). to a cor-The

n). A t for

Page 51: Dissertation on Sugar Production in Nepal

(b) E

In ththe eimpoFigurin threducNEVoccurpossiachie

Figur

4 . 3

GHGkgCOTablelizerspumptrashemiss

Energy consum

he factory openergy balanortant way tore 11 shows

he plant’s enction in ene

V by 33.5%.rs at a 30% ible from aeve given the

re 11: Effecat the

L i f e ce m i s s i

G emissionsO2eq and thee 4. The shas/chemicals ps and truck

h burning, ansions, with f

mption in the p

perations, thnce of the pro achieve ths the variationergy consumergy consum. The breakreduction in

a technologe current tec

ct of differeethanol pla

c y c l e G Hi o n s

s (per hectare contributioare of produ

is 55 %, wks/tractors cnd returned figures of 3.

39

plant is reduced

here is signiroduction ohis is to savon in NEV mption. It hmption in tkeven point,n energy congical point chnological

nt levels of nt on NEV

H G b a l a

re) from sugon from diffuction and thwhile diesel uconstitutes 2residues ha

9%, 6.3% an

d

ificant potenof bioethanove energy (p

V resulting frhas been fothe plant he, when NEVnsumption. of view, itsettings of t

f energy convalues

a n c e s a n

garcane farmferent activihe total appused to pow29.9%. Humave small shnd 4.9% res

ntial to impol in Nepal. power and hrom a reducund that a elps to incrV reaches zAlthough tht is difficulthe plant.

nsumption

n d a v o i d

ming are 36ities is show

plication of fwer diesel w

man labour, ares of the pectively.

rove One

heat). ction 10% rease zero, his is lt to

d e d

625.3 wn in ferti-water cane total

Page 52: Dissertation on Sugar Production in Nepal

40

Table 4: GHG emissions from sugarcane farm land per hec-tare in Nepal (sugarcane yield: 40.61 tonne/ha)

Particulars Emissions (kgCO2eq Ha-1)

% share

Production of fertilizers/ chemicals 1013.34 27.9 Application of N-fertilizers 982.45 27.1 Human labour (fossil fuel inputs) 142.12 3.9 Use of diesel (irrigation and transporta-tion) 1082.72 29.9

Cane trash burning (dry trash) 228.43 6.3 Returned residues 176.20 4.9 Total kgCO2eq emissions per hectare 3625.27

Table 5 shows the results of the estimation of GHG balances. The life cycle greenhouse gas (GHG) emissions from the production of 1 m3 of molasses-based anhydrous bioethanol (EtOH) are 432.5 kgCO2eq, considering the best available molasses-based ethanol conversion plant at Sri Ram Sugar Mills Pvt. Ltd. (SRSM), Nepal. The net avoided emissions come out at 1418.4 kgCO2eq m-3 ethanol, compared to conventional gasoline (of an equivalent energy amount) which is a 76.6% reduction in the life cycle GHG emis-sions (see Table 6). Moreover, the life cycle emissions of EtOH measured as a functional unit, per MJ, is 20.42 gCO2eq MJ-1.

Fossil fuels used in the production of fertilizers/chemicals, diesel combustion (in water pumps and trucks/tractors), and human la-bour contributes 51.9% (224.4 kgCO2eq) of the total emissions. Soil emissions from fertilizer-application and returned residues is the second largest source with a share of 26.8% (116.1 kgCO2eq). Emissions from boilers as a result of bagasse/biogas combustion, trash burning, and combustion of ethanol in vehicles all corre-spond to small shares.

Total life cycle GHG emissions have been calculated to be 1251 kgCO2eq m-3 ethanol when all the sugarcane is used to produce bio-ethanol (without sugar), considering that 1 tonne sugarcane pro-duces 80 liters of ethanol. It should be noted that the allocation has not been made here since bioethanol accounts for the entire GHG share in this case. Avoided emissions are 599.7 kgCO2eq m-3 ethanol or a 32.4% reduction in the life cycle GHG emissions compared to gasoline, thus much lower than the case of molasses-based ethanol.

Page 53: Dissertation on Sugar Production in Nepal

41

Table 5: Life cycle GHG (CO2eq) balance of molasses-based eth-anol (MOE, EtOH) fuel in Nepal

Activities and constituents Emissions (kgCO2eq m-3)

Fertilizer production Phosphorous (P2O5) 5.95 Potash (K2O) 3.89 Nitrogen (N) 48.92 Chemical production Insecticides/pesticides 38.66 Herbicides 4.16 Diesel (irrigation): production & combustion 95.57 Diesel (transport): production & combustion 12.96 Fertilizer application N2O from fertilizer N-application 76.11 CO2 from fertilizer N-application 22.37 Human labour (fossil fuel inputs) 14.25 Cane trash burning 22.90

Returned residues

N2O (spent wash/stillage) 1.06 N2O (filter cake/mud) 9.13 N2O (unburned trash) 7.48

Bagasse combustion in boilers (for heat & power) 35.57 Biogas combustion in boilers 8.56 Sub-total (emissions along the ethanol production chain) 407.53

Emissions from combustion of 1 m3 ethanol (EtOH) in vehicles 25.00

Total life cycle emissions (production & combus-tion of EtOH) 432.53

Table 6: Life cycle comparison of GHG emissions, ethanol (EtOH) and gasoline

Equivalent fuels (EtOH and gasoline) Emissions (kgCO2eq)

Emissions from production and combustion, 1 m3 ethanol (EtOH) 432.53

Emissions from production and combustion, 0.658 m3 gasoline (= 1 m3 of EtOH)

1850.95

Net avoided emissions (kgCO2eq EtOH) 1418.42

% reduction in life cycle GHG emissions 76.63

Page 54: Dissertation on Sugar Production in Nepal

4 . 3

Sensicreasmolathe wIt shbe thprice10.88844.7cycleThe ethanan allnot epal.

Figur

. 1 S e n s

Variat

itivity analyse when theasses. Figurewhole range ould be not

he normal be of molasse8 (keeping 7 kgCO2.eq me GHG emifull trade-o

nol are the location ratieconomically

re 12 : Sensiavoidetion ra(Note: emissiolocation

s i t i v i t y a

tion of alloca

sis shows he market prie 12 depicts

of sensitivited that thebase case foes increases the market

m-3 ethanol wssions comp

off situationsame as thoio of 4.43 (by viable to p

itivity analysed emissionatios for sugDots on the p

ons and % avon ratio, i.e. 22.

42

a n a l y s i s

ation ratio re

how the lifeices change the result ofity from theaverage allor analysis, wtwo-fold, tprice of su

which is a 5pared to gas, i.e. when

ose of convebreak-even pproduce mo

sis for life cys (%) as a fugar and molaprimary and seoided emission2:1 (molasses:

( G H G b

elated to molas

e cycle GHGtowards a h

f GHG emie allocation rocation ratiowas 22.2. Wthe new allougar consta54.4% redusoline (also,the life cycentional gas

point). Belowolasses-based

ycle GHG emunction of dasses condary y-axis

ns respectively sugar)

a l a n c e s )

sses price

G emissionshigher priceissions, coveratio of 24 to, considere

When the maocation ratioant) would ction in the, see Figure cle emissionsoline, occurw this point,d ethanol in

missions andifferent allo

s represent theat the base ca

s in-e for ering to 4.

ed to arket o i.e. give

e life 12).

ns of rs at , it is Ne-

d ca-

e total ase al-

Page 55: Dissertation on Sugar Production in Nepal

Withconsution),ramefromIt cangen-fof dienitrolevel appliand 4sugarthe liin theof 40m-3 e83.5%Nepaprove

Figur

Alternayield

h a variationumption of , the life cyc

eters have bem the present

n be observfertilizer hasesel and pesgen-fertilizeof 506 kgC

ication of pe452 kgCO2eqrcane yields ife cycle GHe cane yield 0.61 tonnes/ethanol (14.% comparedal. Thereforements.

re 13: Sensitputs

ation of m

n in the threpesticides, ncle GHG emeen varied frt value. Figuved that thes a higher imsticides. Forer will lead t

CO2eq m-3 ethaesticides woq m-3 ethanol are improv

HG emission(i.e. 71 tonn

/ha could re4 gCO2eq M

d to gasolinere, there is

tivity analys and sugarca

43

material/ener

ee importannitrogen-fertmissions havrom a 75% rure 13 showe productionmpact on GHr example, ato an increaanol, while d

ould only incl respectivelyved, there isns (see also nes per hecteduce GHG

MJ-1) and ave. Cane yield

plenty of

sis for variatane yield in

rgy inputs,

nt input parartilizer, and dve been estireduction to

ws the resultsn and appliHG emissioa 50% increaase in GHGdiesel consucrease the ey. On the ots a significaFigure 13).tare) from th

G emissions voided emisds are currenscope for

tions in matNepal

and sugar

ameters, namdiesel (for irimated. The

o a 75% incrs of the analication of nons than thease in the us

G emissions umption andemissions tother hand, want reductioA 75% incrhe present vto 306 kgCsions wouldntly quite loimmediate

terial/energy

rcane

mely riga-e pa-rease lysis. itro-

e use se of to a

d the 480

when n in

rease value CO2eq d be w in im-

y in-

Page 56: Dissertation on Sugar Production in Nepal

44

4 . 3 . 2 A l t e r n a t i v e s c e n a r i o s a n d s y s t e m e x p a n s i o n

Alternative scenarios in wastewater treatment plants

GHG emissions from wastewater (effluent or spent wash) treat-ment plants at the factories/distillery plants are quite significant, and are related to the types of treatment process used. The Anaer-obic Digestion Process (ADP, a biological digester) and Pond Sta-bilization (PS, also called the lagoon system) are two common treatment practices for the treatment of wastewater from sugar and distillery industries. The present scenario (at the plant level) in SRSM comprises the best available case in Nepal with wastewater treatment facilities treating 100% of the wastewater, using ADP to recover biogas, whereby no leakage of biogas is allowed into the atmosphere. Recovered biogas is fed directly into boilers as fuel. Given a scenario of 100% biogas leakage into the open atmos-phere from ADP, the total amount of emissions would be 2602.1 kgCO2eq (per hectare). The Pond Stabilization (PS) process releases 1551.4 kgCO2.eq Ha-1 into the atmosphere. A close examination of the GHG emissions associated with each of these waste treatment options shows that the ADP treatment process, without any biogas leakage, is preferred.

The results of emissions from ADP and pond stabilization (PS) treatment plants have been scrutinized. When 100% of the spent wash is sent through the pond stabilization process, the life cycle emissions may increase to 118% with a value of 4032 kgCO2eq m-3

ethanol. When 50% of the spent wash is treated using PS and the remaining 50% fed into the ADP (with biogas recovery), there is a 21% increase in emissions, compared with those for gasoline. However, if 25% of the spent wash is treated using PS and the re-maining 75% with the ADP, the emissions are reduced by 28% to a level of 1332 kgCO2eq m-3 ethanol, as shown in Figure 14. Thus, the installation and operation of the ADP in sugar and distillery factories not only recovers energy but also reduces the life cycle GHG emissions.

Page 57: Dissertation on Sugar Production in Nepal

Figur

WhenfromsionsGHGshowthe rathen emissfore, of th

As foexcesSugardors fer fr– Ma

re 14: Life ment

n considerinm ADP), 10%s compared G emissionsws the total ange of 5 – the life cyc

sions level it is essenti

he emissions

Grid ctechnolo

ound in the ss bagasse ar mills/factowhere many

rom power ay), the perio

cycle emissiof wastewat

ng the leaka% leakage w

to gasolines becomes emissions,25%. If the

cle GHG emof its counial to avoid reduction f

connection foogical impro

estimation oarising fromories in Nepy industrial shortages, eod when hy

45

ions in the ter in PS and

age of biogwould avoid e. In this ca1038 kgCOtaking intoe total leakagmissions of nterpart, con

leakage in ofrom fuel sub

for electricityvements

of the net enm the sugar p

pal are locatcomplexes o

especially in ydroelectricit

case of pard ADP

gas from a b44% of thease, the val

O2eq m-3 ethaaccount bioge of biogasbioethanol

nventional gorder to takbstitution.

y from exce

nergy balancproduction ted near to operate. Th

n the dry seaty generatio

rtial treat-

bio-digester e life cycle elue of life canol. Figureogas leakages exceeds 23will surpass

gasoline. Thke full advan

ess bagasse

ces, there is chain at SRindustrial ce industries

ason (Decemon is limited

(i.e. mis-cycle e 15 es in 3.4% s the here-ntage

and

17% RSM. orri-suf-

mber and

Page 58: Dissertation on Sugar Production in Nepal

the hstandthe gtricitytricityrenewemisscurreexcesboth

Figur

Withdiese(-213cane/emissGHGlassessionsnotedtween

harvesting d-by diesel pgrid. Excessy to the gridy produced wable bioelsions. It shoent installed ss electricityeconomic a

re 15: Life cy

h the avoidanel-based elec3 kgCO2eq /ethanol prosions into th

G emissionss-based ethas from differd that the an sugar and

of sugarcanpower plants bagasse cad along thesby the diese

lectricity wiould be notcapacities c

y though imand environm

ycle emissio

nce of GHGctricity, the tm-3 ethanooduction-chhe atmosph is 112% baanol (EtOH)rent activitieavoided GH

d molasses w

46

ne occurs. ts when no an be used tse industrial el power plath a conse

ted that boilan operate i

mproved effmental value

ons in the ca

G emissions total emissio

ol) indicatinhain absorbs here. The toased on the ), when comes are shownHG emissiowhen consid

Industries, electricity is

to generate acorridors. P

ants can be equent redulers and turin such a wa

fficiency, whe.

ase of biogas

through theons of ethan

ng that the GHG rathe

otal percentaproduction

mpared withn in Figure

ons are not dering the ex

therefore, s available fand supply ePart of the ereplaced by

uction in Gbines with tay as to genehich would

s leakage

e substitutionol are negae entire suer than releaage reductioof 1 m3 of

h gasoline. E16. It shoulpartitioned

xpansion of

run from elec-elec-

y this GHG

their erate add

on of ative ugar-asing on in

mo-mis-d be be-f the

Page 59: Dissertation on Sugar Production in Nepal

system618 show

Techand pturbinrohit resouhuge cane bioeltrashoptimemiss

Figur

m with surkgCO2eq an

wn in Figure

hnological impower plantne, can gene

t and Michaurce efficien potential tosystems of

lectricity to rh/wastes formization of sions.

re 16: GHGanol psurplu

rplus electricnd 28 kgCO

16.

mprovementt (CHP), suerate 1 kWh

aelowa, 2007nt than the o trade-off tf Nepal by replace dieser electricity

industrial p

G emissions production us electricity

47

city. Sugar aO2eq at an al

ts in the bagch as a high

h electricity f7) which is m

ones foundthe entire Ggenerating el power plageneration, processes c

shares fromchain in N

y to substitut

and molassllocation rat

gasse-fuelledh pressure afrom 1.6 kgmore than d in Nepal.

GHG balancand selling

ants. The utand the im

ould furthe

m different stNepal (in thte diesel)

es actually tio of 22.2:

d combined and temperag of bagasse five times m. Thus, therces in the su

bagasse-fuetilization of

mprovement er reduce G

tages of the e case of u

emit 1 as

heat ature (Pu-

more re is ugar-elled cane and

GHG

eth-using

Page 60: Dissertation on Sugar Production in Nepal

48

4 . 4 C o m p a r i s o n o f r e s u l t s w i t h o t h e r s t u d i e s

Several studies have estimated the life cycle energy and GHG bal-ances of bioethanol derived from various feedstocks, such as sug-arcane, cassava, corn and cane-molasses. Macedo et al., (2008) found that the energy yield ratio in the production phase of sugar-cane was 9.3 in Brazil during 2005/06, taking into account the di-rect consumption of external fuels and electricity, the energy re-quired for the production of chemicals and materials, and the addi-tional energy necessary for the manufacture, construction and maintenance of equipment and buildings. The total GHG emis-sions for anhydrous ethanol production were 436 kg CO2eq m-3 ethanol in the same period and could decrease to 345 kgCO2eq m-3 for a conservative scenario in 2020 (Macedo et al., 2008). Cane productivity and ethanol yield were the most important parameters affecting the estimation of GHG balances. However, the study has not dealt with wastewater treatment of spent wash.

Nguyen et al. 2007a have calculated the NEV and NREV for cas-sava-based bioethanol in Thailand with respective positive values of 8.8 MJ/L and 9.15 MJ/L. Shapouri et al. (2004) reported that the net energy balance (energy yield ratio) for producing corn eth-anol in the USA was 1.67. The results of NEV and NREV for cas-sava fuel ethanol, as reported by Dai et al. (2006), were 7.47 MJ/L and 7.88 MJ/L respectively, in the case of China. Nguyen et al. (2008b)’s life cycle analysis of sugarcane-molasses-based ethanol calculated the values of NEV (-5.67 MJ/L), NREV (5.95 MJ/L), and energy yield ratio (6.12 per MJ petroleum inputs) in Thailand. The study was quite similar to that of molasses bioethanol in Ne-pal. However, the results contrast with the values of NEV (-13.05 MJ/L) and NREV (18.36 MJ/L) found in the Nepalese case. In the Thai case, the plant’s energy requirements are not met by ba-gasse alone; rice husks and wood wastes are also used as supple-mentary fuels in the sugar milling process. Coal is a major fuel in the ethanol conversion process, and biogas is not utilized for pro-cess energy. At the same time, excess electricity is sold to the grid as energy outputs. In the case of Nepal, the difference in NEV is due to higher total energy inputs (fossil fuel plus renewable) while favourable conditions for NREV occur, since energy requirements are mostly met by renewable sources.

Page 61: Dissertation on Sugar Production in Nepal

49

Nguyen et al. (2007b) have analysed the life cycle GHG emissions for molasses-based ethanol in Thailand, demonstrating that there is a 31.3% increase in GHG emissions (per liter of ethanol) with an allocation ratio (between sugar and molasses) of 8.6:1. Emissions from anaerobic pond stabilization contributed the largest share, of 54.1%. However, the study also showed that biogas recovery from 100% spent wash could reduce GHG emissions by 60.6% com-pared to conventional gasoline, and further improvements are pos-sible, up to an 88.8% reduction. In comparison, a 76.6% reduction in total emissions per liter of ethanol is observed in the Nepalese case, assuming the best case currently available in one of the estab-lished sugar factories.

Greenhouse gas savings (tonnes of CO2eq per hectare) in sugarcane bioenergy systems have also been identified by Nguyen et al. (2010) in the sugar industry in Thailand. Electricity generation from cane trash/residues and excess bagasse, and energy extrac-tion from stillage (wastewater) would reduce GHG emissions. When considering molasses as a feedstock for ethanol production in the average Brazilian mill, Gopal and Kammen (2009) found that the life cycle GHG emissions were 15.1 gCO2eq MJ-1 , and sugar and molasses prices play a key role in determining the emissions. In comparison, emissions of 20.4 gCO2eq MJ-1 of GHGs were found in the case of Nepal, for sugarcane-molasses-based ethanol. The life cycle emissions in the production and use of 1 m3

of cassava-based ethanol were 964 kgCO2eq, which corresponds to 62.9% of the total reduction in emissions Nguyen et al. (2007c).

Moreover, Blottnitz and Curran (2007) conducted a review of assessments of bioethanol as a transporation fuel from the net energy, greenhouse gas and environmental life cycle perspective, comparing energy yield ratios and GHG balances, though with differing assumptions and system boundaries. The values of GHG emissions and energy yield ratios differ significantly depending on the feedstock used and the production practices applied. Recent literature also points out that it is essential to distinguish between the bioenergy systems referred to, the energy conversion technologies used and the resultant energy and GHG balances, when contrasting LCA and sustainability issues for different biofuels (Gnansounou et al., 2009 ; Cherubini et al., 2009; Hoef-nagels et al., 2010). These studies are important points of reference for the evaluation of biofuels, but an in depth comparison of the

Page 62: Dissertation on Sugar Production in Nepal

50

energy values and GHG emissions of ethanol production methods is difficult without precisely defining the methodological approach, system boundaries, allocation methods, and specific feedstock characteristics, among other things. Thus, unified methodological procedures in the production of bioethanol are required globally, including LDCs.

4 . 5 P r o s p e c t s f o r s u s t a i n a b l e d e v e l o p m e n t

Nepal has great potential to produce molasses-based ethanol and for it to be used as part of a blend in gasoline-run vehicles. The in-creased use of biofuels not only reduces dependency on fossil fuels but also reduces the greenhouse gas (GHG) emissions and local air pollution caused by vehicular emissions. In addition, the produc-tion of biofuels can serve as a driver for improvements in agricul-ture. The prospects for sustainable development are discussed in detail in Silveira and Khatiwada (2010). This section highlights the key issues related to the potential for ethanol to contribute to sus-tainable development in Nepal.

4 . 5 . 1 E t h a n o l p r o d u c t i o n p o t e n t i a l i n N e p a l

With an installed production capacity of 30 m3 of bioethanol per day, Sri Ram Sugar Mills Pvt. Ltd. (SRSM) can produce 4,500 m3

annually, assuming the plant runs for 150 crop days. If SRSM pur-chased molasses from other sugar mills, then the production ca-pacity reaches 8,760 m3, assuming that the ethanol plant runs dur-ing the whole year at a plant utilization factor of 80%.

Of the total sugarcane production in 2006/07 (i.e. 2.6 million tonnes), 70% was processed by sugar industries to produce sugar in Nepal. 78,684 tonnes of molasses were generated, assuming an average production of 4.3% of the sugarcane milling. Thus the bi-oethanol production potential was 18,045 m3 for the same year.

4 . 5 . 2 S u b s t i t u t i n g g a s o l i n e w i t h E 1 0 a n d E 2 0 i n t h e K a t h m a n d u V a l l e y

The Kathmandu Valley consumes 71,338 m3 of gasoline (70% of the gasoline imported to Nepal) per year. 56% of the country’s au-tomobiles run in the valley. Most light automobiles, such as cars,

Page 63: Dissertation on Sugar Production in Nepal

51

jeeps and vans, and a huge fleet of two-wheeler motor-bikes use gasoline. Automobiles fuelled by gasoline can use E5-E20 blended fuel in the existing engine with only minor adjustments, and it also has a high octane number (ON) with better combustion efficiency.

When considering the energy content or lower heating value (LHV), and the volumetric equivalency between the ethanol blend (E10) and pure gasoline, i.e. one liter of pure gasoline is equal to 1.0354 liters of E10, it is found that the substitution of the gasoline presently used in the Kathmandu Valley adds up to a total of 73,864 m3 of E10, which corresponds to a blend of 66,478 m3 gas-oline and 7,386 m3 of ethanol. It should be noted that the LHV of anhydrous ethanol (99.5% v/v, EtOH) and gasoline are 21.183 MJ/L and 32.192 MJ/L respectively. As examined by Silveira and Khatiwada (2010), The Kathmandu Valley could save 4,860 m3 of gasoline per year, which is a reduction in imports of 6.8% if gaso-line automobiles went for E10. The demand for E10 could be met if SRSM purchased molasses from other sugar mills and ran the dehydration ethanol plant annually at a plant utilization factor of 68% assuming other sugar mills were not equipped to produce an-hydrous ethanol (EtOH).

When the vehicles go for an E20 blend, a reduction of 14% in gasoline imports, i.e. an annual saving of 10,078 m3, is achievable, which corresponds to an ethanol requirement of 15,315 m3 in a year. This annual requirement is still lower than the total potential capacity of the sugar mills, given the availability of molasses for ethanol production.

Looking at the economics of petroleum imports, Nepal Oil Cor-poration (a state owned enterprise, NOC) accumulated annual losses of US$ 78 million in 2007/08, US$ 27 million in 2006/07, and US$ 55 million in 2005/06. With the introduction of ethanol blends, direct annual import savings of US$ 4.9 million (with E10), and US$ 10.1 million (with E20) can be achieved, given the current retail price of gasoline.

4 . 5 . 3 E n v i r o n m e n t a l g a i n s o f i n t r o d u c i n g E 1 0 a n d E 2 0 i n t h e K a t h m a n d u V a l l e y

The Kathmandu Valley suffers from a severe air pollution problem due to increased vehicular emissions and its specific geographic lo-

Page 64: Dissertation on Sugar Production in Nepal

52

cation. Various international studies have shown that the use of biofuels not only reduces dependency on fossil fuels but also re-duces greenhouse gases and local air pollution caused by vehicular emissions. In Nepal, the environmental life cycle analysis of an E10 and pure gasoline car shows that E10 fuel works better than pure gasoline with regards to greenhouse gas emissions, the release of carcinogens, and ozone layer destruction, although the quantity of substances causing acidification/eutrophication increases with the E10 (Khatiwada, 2007). A piece of research conducted to in-vestigate the performance of E10 and E20 in automobiles in the Kathmandu Valley showed ethanol blends work better than con-ventional gasoline (AEPC, 2008).

The Kathmandu Valley consumed 71,338 m3 of gasoline, 46,003 m3 of diesel, and 5400 tonnes of LPG in the transport sector in 2006/07. The total CO2 emissions resulting from the consumption of these transport fuels were estimated to be 304,000 tonnes (pet-rol: 54.4%, diesel: 40.3%, and LPG: 5.3%). The introduction of E10 could avoid 11,283 tonnes (7% of total gasoline emissions) of CO2 emissions, while E20 could contribute to the avoidance of 23,397 tonnes of CO2 emissions, which is 14% of the total gaso-line emitted in a year in 2006/07 (Silveira and Khatiwada, 2010).

4 . 5 . 4 O t h e r i m p o r t a n t a s p e c t s o f s u s t a i n a b l e d e v e l -o p m e n t

First generation bioethanol, derived from food crops such as corn/maize and sugarcane is often debated when it comes to food security and land use. In Nepal, the production of bioethanol oc-curs from the low-value by-product of the sugar milling process: molasses. Without compromising sugar and other indigenous sug-ar-based food products (such as Chaku and Shakhar), Nepal could today produce enough bioethanol to introduce an E20 blend for gasoline replacement in the Kathmandu Valley (Silveira and Khatiwada, 2010). Therefore, there is no trade-off between food and fuel in terms of bioethanol production in Nepal at its present scale. Our study has also shown that there is still a significant po-tential to increase cane yields, which would guarantee a significant increase in ethanol production without the need to bring more land into cultivation.

Page 65: Dissertation on Sugar Production in Nepal

53

Given the present conditions, sugar industries are self-sufficient in their energy requirements. Bagasse generates the heat and electrici-ty required to run the whole plant. Excess bagasse could be used to provide surplus electricity to replace diesel-powered electricity in the industrial corridor. Bioethanol derived from molasses could replace gasoline in the transport sector. Having made more effi-cient utilization of bagasse and cane-trash, surplus bioelectricity could be generated to provide power for nearby industries or to provide lighting for the rural poor, with the help of rural electrifi-cation in the countryside, where 61% of the population still lack electricity. Therefore, the development of sugarcane bioenergy sys-tems would enhance energy security.

Of the total land area of 14.72 million hectares in Nepal, cultivated land accounts for 21%, non-cultivated 7%, forest including shrubs 39.6%, grass land 12% and water bodies and others 20.4%. Culti-vated land is used for cereal/food products, cash crops, pulses, and fruit/vegetables. Cash crops consist of oilseed, potato, tobac-co, sugarcane, and jute. The production of cash crops takes place in 13.2% of the total cultivated land, of which 14.5% is allocated for sugarcane farming. Thus, it can be observed that the area oc-cupied by sugarcane is significantly smaller than the area dedicated to other cash or food crops. At present, sugarcane yields reach an average of 40.6 tonnes/ha, and could be improved with the help of regional experience and practice in sugarcane cultivation. Mechani-zation of agricultural practices should also be considered in the medium term. This would enhance food production as well as that of energy products without the need for more cultivated land.

Wastewater (spent wash), generated by bioethanol conversion units, is treated using an Anaerobic Digestion Process (ADP) with biogas recovery, and the final effluents are only discharged into water bodies, within acceptable limits, after the treatment has met the effluent standards set out by the environmental protection rules/regulations in Nepal. If the wastewater treatment plant is properly operated and maintained, there will be no significant wa-ter pollution resulting from distillery operations.

The institutional collaboration between concerned private and public stakeholders, including donor agencies/partners plays an important role in the sustainability of any development project. The institutional set-up and public-private-partnerships seem weak

Page 66: Dissertation on Sugar Production in Nepal

54

in the case of Nepal. For example, government policy on the in-troduction of the E10 blend was enacted in 2004 but has not yet been implemented due to institutional bottle-necks.

Nepal is currently at the verge of a period of political transition, and internal conflicts still exist within the country, especially in the plains of the south, which affects sugarcane production and productivity. Proper renewable energy policy is required to boost the production and use of bioethanol, providing on the one hand incentives for sugarcane farmers and industries who want to make the investment in bioethanol production and, on the other hand, the proper institutional conditions to promote the switch to a new fuel.

4 . 6 R e s u l t s o f s u s t a i n a b i l i t y a s s e s s m e n t : a s u m m a r y s h e e t

With the above discussion on the development of sustainability criteria, and the findings from the case of molasses-based bioetha-nol production and use in Nepal, a summary sheet of sustainability criteria for bioethanol production is presented in Table 7. While Table 1 indicated a large number of important criteria in the con-text of bioethanol production and use, Table 7 shows a summary of the most important messages derived from the in depth analysis carried out using some of these sustainability criteria. The second column summarizes the main contributions or arguments of the thesis, indicating what can be achieved in the short run.

Page 67: Dissertation on Sugar Production in Nepal

55

Food vs. energy security

C. Social

Energy security and diversi-

fication

Savings on oil import

B. Econom

ic

Wastew

ater managem

ent

Local air pollution

Life cycle GH

G balances

CO2 em

issions from fuel

substitution in automobiles

Life cycle energy balances

Fossil fuels substitution

A. E

nvironmental

Criteria

Table 7: Evaluating selected sustainability criteria for bioethanol production and use in N

epal – Summ

ary of thesis results

Molasses, a low

-value by-product of the sugar milling process is used for bioethanol production w

ithout com

promising the production of sugar and other indigenous sugar based food products (such as Chaku and

Shakhar).

National bioethanol potential =

18 million liters. Bioethanol can replace im

ported gasoline, enhancing do-m

estic energy security. Moreover, a com

bined heat and power (CH

P) plant, fuelled by bagasse and recovered biogas, provides energy at the plant level, w

hile surplus bioelectricity can be sold to the grid.

Direct annual savings are U

S$ 4.9 million (using E

10) and US$ 10.1 m

illion (using E20) in the K

athmandu

Valley

Exam

ination of the wastew

ater treatment processes show

s that it is essential to treat distilleries’ wastew

ater (spent w

ash) using the Anaerobic D

igestion Process (AD

P) with biogas recovery. Biogas contributes 4%

of total available prim

ary energy, and AD

P (without biogas leakage) contributes to reducing life cycle G

HG

em

issions.

Bioethanol blends reduce air pollution problems in the K

athmandu V

alley

Life cycle GH

G em

issions = 433 kgCO

2eq m-3 (or 20.4 gCO

2eq .MJ -1.); net avoided em

issions = 1418 kgCO

2eq

m-3 ethanol or a 76.6%

reduction in the life cycle GH

G em

issions compared to conventional gasoline

11,283 tonnes and 23,397 tonnes of CO2 are avoided by substituting E

10 and E20 for gasoline respectively.

Net renew

able energy value (NRE

V) =

18.36 MJ/L; N

et energy value (NE

V) =

- 13.05 MJ/L; Total energy

(fossil and renewable) inputs =

34.26 MJ /L; E

nergy yield ratio = 7.47

With the use of bioethanol blends in the transport sector, the consum

ption of imported gasoline is reduced.

Gasoline savings are 4,860 m

3 (for E10) and 10,078 m

3 (for E20) per year in the K

athmandu valley.

Contributions of the thesis

Page 68: Dissertation on Sugar Production in Nepal

56

5 Conclusions and future work

5 . 1 C o n c l u s i o n s

This study has estimated the net energy balance of the production of molasses-based bioethanol in Nepal, examined the GHG bal-ances associated with the production and use of bioethanol in the country, and showed how bioethanol production and use can con-tribute towards sustainable development. The thesis now turns to the three key questions that were asked at the beginning, as a way of putting the analysis into perspective and drawing appropriate conclusions.

(a) Is bioethanol energy efficient i.e. how much energy does it take to produce one liter of bioethanol?

The fossil fuel required to produce 1 liter of molasses-based bio-ethanol (MOE or EtOH) is 2.84 MJ, giving a good energy yield ra-tio (7.47). The net renewable energy value (NREV) is 18.36 MJ/L, and a higher value of NREV indicates the low amount of fossil fuels used in the production cycle of ethanol in Nepal. Thus, bio-ethanol production is energy efficient in terms of the amount of fossil fuel used to produce it. The total energy (fossil fuel and re-newable) requirement is 34.26 MJ/L, which is higher than the en-ergy content of 1 liter of bioethanol (i.e. 21.2 MJ/L), giving a nega-tive NEV ( 13.05 MJ/L). However, low quality biomass feedstock i.e. molasses (in terms of market and energy values) is converted into a high quality modern renewable transport fuel. In addition, there is plenty of room for significant improvements in the short term.

The life cycle renewable energy contribution amounts to 91.7%, required to produce 1 liter of EtOH, since bagasse, biogas and non-motorized transportation cover most of the operations with the exception of the application of fertilizers/chemicals and irriga-tion. There is huge potential for energy savings in sugar milling and ethanol production: a 10% reduction in energy consumption

Page 69: Dissertation on Sugar Production in Nepal

57

helps to increase NEV by 33.5%. An improvement of 30% in the efficiency of the plant will result in a break-even situation for NEV, i.e. a point where the total energy input into the system is equal to the output in terms of the energy content provided by bi-oethanol. This is fully possible with readily available technology. (b) How many greenhouse gas (GHG) emissions and savings occur in the pro-

duction and use of bioethanol?

The total life cycle emission of bioethanol is 433 kgCO2eq m-3 (i.e. 20.4 gCO2eq MJ-1), which is a 76.6% reduction in GHG emissions compared to conventional gasoline from a life cycle perspective. Thus, the production and consumption of bioethanol saves 1418 kgCO2eq m-3 of GHG emissions when an equivalent volumetric amount (i.e. 1 m3 ethanol = 0.658 m3 gasoline) of gasoline is re-placed by ethanol as the transport fuel in Nepal.

(c) What are the direct benefits of bioethanol substitution in the transport sec-tor?

The direct benefits of bioethanol substitution in the transport sec-tor are: replacement of gasoline fuel, enhancement of energy secu-rity, diversification of energy products, improvement of local air quality in the Kathmandu Valley, saving hard foreign currency, and a reduction in GHG emissions. The variation in the price of molasses has a significant effect on the net energy values, energy yield ratio, and GHG balances. When the market price of molasses doubles, the energy yield ratio is re-duced to 3.88 (a 48.8% reduction). NEV and NREV also decrease by 90.2% and 14.7% respectively. On the other hand, the life cycle GHG emissions would be 844.7 kgCO2eq m-3 ethanol given a two-fold increase in the price of molasses.

The analysis of scenarios concerning the choice of wastewater treatment plant, from either Anaerobic Digestion Process (ADP) or Pond Stabilization (PS), shows that ADP with biogas recovery significantly reduces GHG emissions, particularly if leakages are avoided. The pond stabilization (PS) treatment process contrib-utes to an alarming increase in GHG emissions. The expansion of the system, with the sale of surplus electricity obtained from the

Page 70: Dissertation on Sugar Production in Nepal

58

combustion of excess bagasse, could also help to reduce GHG emissions.

This thesis has identified a number of opportunities for improve-ments to the net energy balance and GHG emissions along the bi-oethanol production chain. Improvements can be achieved through: (a) improvement in cane yields, with the help of the mod-ernization of agricultural practices, (b) cane bagasse and trash/wastes being used efficiently to generate bioelectricity, and (c) the technological upgrading and optimization of industrial op-erations. However, it is difficult to compare and benchmark these improvements with similar studies carried out elsewhere due to a lack of methodological coherence in evaluating bioethanol produc-tion globally.

In spite of the international debate on biofuels, bioethanol produc-tion in Nepal does not pose any threats to food security since the feedstock is a low-value industrial by-product obtained from the sugarcane milling process. Nepal can produce 18 million liters of bioethanol annually without compromising the production of food products, and savings of US$ 10 million could be possible through the implementation of the E20 blend in the Katmandu Valley to replace conventional gasoline. Vehicles running on ethanol blends (E10 or E20) also release less air pollutants compared to pure gas-oline.

It is envisaged that favorable governmental policies, such as man-datory bioethanol blends and incentives/subsidies for sugarcane farmers and private investors, will be put in place to explore the bioethanol potential in Nepal. Proper institutional mechanisms and coordination amongst concerned stakeholders, including both pri-vate and public sectors, are required for the production and com-mercialization of bioethanol in Nepal. Both political and institu-tional concerns have become the most urgent issues to address at this stage, when mature conversion technologies are already avail-able and accessible in the region. The insight provided using the example of this country could also motivate the assessment and production of bioethanol in other LDCs.

Page 71: Dissertation on Sugar Production in Nepal

59

5 . 2 F u t u r e w o r k s

(a) This research is focused on the direct economic and envi-ronmental benefits, along with the life cycle energy assess-ment and GHG balances of bioethanol production in Nepal. The generation of bioelectricity from bagasse and cane trash/wastes has not been discussed in detail. There is a huge potential, not only to generate bioelectricity in order to improve net energy balances and efficiency, but also to trade-off entire GHG balances in the sugarcane systems of Nepal. Therefore, life cycle economic and social sustainabil-ity, and the optimization of relevant sustainability indicators, such as net energy and GHG balances and the utilization of cane trash/wastes for electricity generation is another step worthy of investigation.

(b) The development of life cycle case studies for sustainability assessment, and the optimization of sugarcane-based com-mercial energy sources (i.e. bioelectricity and bioethanol) are important for many least developed countries (LDCs). In this regard, a similar case study in one of the African LDCs would be interesting to investigate. After the compilation of field data from the production chain of bioethanol in differ-ent LDCs, the modelling of climate, energy, land use, envi-ronmental performance, and the consumption of other natu-ral resources, such as water, could be carried out.

(c) Last but not the least, in order to allow a comparative analy-sis of the sustainability assessment of bioethanol production from sugarcane feedstock, methodological coherence and unification should be established and benchmarked globally in the context of the evaluation of sustainable bioenergy sys-tems for product certification, and international trade from the life cycle perspective. Therefore, the evaluation of sugar-cane bioethanol, with methodological improvements to-wards international common ground, is the next step of this research work.

Page 72: Dissertation on Sugar Production in Nepal

60

6 References

Abbasi, T., Abbasi, S.A., 2010. Biomass energy and the environ-mental impacts associated with its production and utilization. Renewable and Sustainable Energy Reviews 10, pp. 919 – 937.

AEPC, 2008. Report on Assessing the Economic, Technical and Environmental Aspects of Using Petrol-Ethanol Blend in the Automobiles in Nepal. Kathmandu, Nepal. Alternative Energy Promotion Centre (AEPC), Government of Nepal.

Afgan, H.A., Carvalho, M.G., Hovanov, N.V., 2000. Energy sys-tem assessment with sustainability indicators. Energy Policy 28, pp 603 - 612.

Al-Hasan, M., 2003. Effect of ethanol–unleaded gasoline blends on engine performance and exhaust emission. Energy Conver-sion and Management 44, pp. 1547–1561. Available at http://www.erec.org/fileadmin/erec_docs/Projcet_Documents/RESTMAC/Brochure5_Bioethanol_low_res.pdf

Azapagic, A., Clift, R., 1999. Life cycle assessment and multiobjec-tive optimisation. Journal of Cleaner Production 7, pp. 135–143.

Bake, J.D.W., Junginger, M., Faaij, A., Poot, T., Walter, A., 2009. Explaining the experience curve: Cost reductions of Brazilian ethanol from sugarcane. Biomass and Bioenergy 33, pp. 644 - 658.

Balat, M., Balat, H., 2009. Recent trends in global production and utilization of bio-ethanol fuel. Applied Energy 86, pp 2273-2282

Balat, M., Balat, H., Oz, C., 2008. Progress in bioethanol pro-cessing. Progress in Energy and Combustion Science 34, pp 551-573

Batidzirai, B., Faaij, A.P.C., Smeets, E., 2006. Biomass and bioen-ergy supply from Mozambique. Energy for Sustainable Devel-opment, Volume X No. 1. pp. 54 - 80.

Blottnitz, H.V., Curran, M.A., 2007. A review of assessments con-ducted on bio-ethanol as a transportation fuel from a net energy, greenhouse gas, and environmental life cycle perspective. Journal of Cleaner Production 15, 607- 619.

Brennan, L., Ownede, P., 2010. Biofuels from microalgae—A re-view of technologies for production,processing, and extractions

Page 73: Dissertation on Sugar Production in Nepal

61

of biofuels and co-products. Renewable and Sustainable Energy Reviews 14, pp. 557 - 577.

Buchholz, T., Luzadis, A.V., Volk, T.A., 2009. Sustainability crite-ria for bioenergy systems: results from an expert survey. Journal of cleaner production 17, S86–S98.

Cardona, C.A., Sanchez, O.J., 2007. Fuel ethanol production: Pro-cess design trends and integration opportunities. Bioresource Technology 99, pp 2415 – 2457.

Cherubini, F., Bird, N. D., Cowie, A., Jungmeier, G., Schlamading-er, B., Gallasch, S.W., 2009. Energy- and greenhouse gas-based LCA of biofuel and bioenergy systems: Key issues, ranges and recommendations. Resources, Conservation and Recycling 53 , 434–447

Costa, R.C., Sodre, J.R., 2010. Hydrous ethanol vs. gasoline-ethanol blend: Engine performance and emissions. Fuel 89, pp 287 – 293.

Cramer, J., Wissema, E., Lammers, E., Faaij, A., Hamelinck, C., Bergsma, G., van den Heuvel, E., Junginger, M., Smeets, E., 2006. Criteria for sustainable biomass production, Netherlands.

Creutzig, F., He, D., 2009. Climate change mitigation and co-benefits of feasible transport demand policies in Beijing. Trans-portation Research Part D: Transport and Environment 14, pp 120-131.

Dai, D., Hu, Z., Pu, G., Li, H., Wang, C., 2006. Energy efficiency and potentials of cassava fuel ethanol in Guangxi region of Chi-na. Energy Conversion and Management 47, 1686–1699.

Demirbas, A., 2008. Biofuels sources, biofuel policy, biofuel econ-omy and global biofuel projections. Energy Conversion and Management 49, pp. 2106–2116.

DETEC, 2004. Sustainability assessment Conceptual framework and basic methodology. Department of Environment, Transport, Energy and Communications (DETEC), Federal Office for Spa-tial Development ARE (2004), Zurich, the Switzerland.

DSDG, 2005. Dutch Sustainable Development Group (DSDG). Feasibility study on an effective and sustainable bio-ethanol pro-duction program by least developed countries as alternative to cane sugar export. Ministry of Agriculture, Nature and Food Quality (LNV), The Hague, The Netherlands, May 20; 2005, <li-brary.wur.nl/WebQuery/catalog/lang/1845441>.

Elghali. L., Cliff, L.R., Sinclair, P., Panoutsou, C., Bauen, A., 2007. Developing a sustainability framework for the assessment of bio-energy systems. Energy Policy 35, pp 6075 – 6083.

Page 74: Dissertation on Sugar Production in Nepal

62

Escobar, J.C., Lora, E.S., Venturini, O.J., Yanez, E.E., Castillo E.F., 2009. Biofuels: Environment, technology and food security. Renewable and Sustainable Energy Reviews 13, pp 1275 - 1287.

EUBIA, 2005. Creating markets for renewable energy Technolo-gies EU RES Technology Marketing Campaign - Bioethanol production and use. European Biomass Industry Association (EUBIA).

FAO, 2010. Bioenergy and Food Security. The BEFS (Bioenergy and Food Security) analysis for Tanzania. The Bioenergy and Food Security Project, Food and Agriculture Organization of the United Nations (FAO).

Gnansounou, E., Dauriat, A., Villegas, J., Panichelli, L., 2009. Life cycle assessment of biofuels: Energy and greenhouse gas balanc-es. Bioresource Technology 100, 4919–4930.

Goh, C.S.., Lee, K.T., 2010. A visionary and conceptual macroal-gae-based third-generation bioethanol (TGB) biorefinery in Sa-bah, Malaysia as an underlay for renewable and sustainable de-velopment. Renewable and sustainable energy Reviews 14, pp 842 – 848.

Goldemberg, J., Coelho, S.T., Guardabassi, P., 2008. The sustaina-bility of ethanol production from sugarcane. Energy Policy 36, pp. 2086 - 2097.

Goldemberg, J., Coelho, S.T., Nastari, P.N., Lucon, O., 2004. Eth-anol learning curve - the Brazilian experience. Biomass and Bio-energy 26, pp. 301 – 304.

Gopal, A.R., Kammen, D.M., 2009. Molasses for ethanol: the eco-nomic and environmental impacts of a new pathway for the lifecycle greenhouse gas analysis of sugarcane ethanol. Environ-mental Research Letters 4, 1-5.

GRFA, 2009. GHG emission reductions from world biofuel pro-duction and use. Global Renewable Fuels Alliance. Prepared by (S&T)2Consultants Inc. (A research institute in Canada). Availa-ble at http://www.globalrfa.org/pdf/120809_final_report_ghg_emissions_biofuels_1.pdf as accessed on 25 June 2010.

Harijan, K., Memon, M., Uqaili, M.A., Mirza, U.K., 2009. Potential contribution of ethanol fuel to the transport sector of Pakistan. Renewable and Sustainable Energy Reviews 13, 291-295.

Hediger, W., 2000. Sustainable development and social welfare. Ecological Economics 32, pp. 481–492.

Page 75: Dissertation on Sugar Production in Nepal

63

Heller, M.C., Keoleian, G.A., 2003. Assessing the sustainability of the US food system: a life cycle perspective. Agricultural systems 76. pp 1007 - 1041.

Hira, A., 2010. Sugar rush: Prospects for a global ethanol maket. Energy Policy. Article in press. doi:10.1016/j.enpol.2010.05.035

Hoefnagels, R., et al., 2010 Greenhouse gas footprints of different biofuel production systems. Renewable and Sustainable Energy Reviews. doi:10.1016/j.rser.2010.02.014 (article in press).

Hunkeler, D., Rebitzer, G., 2005. The future of lice cycle assess-ment. Internatin Journal of Life Cycle Assessment 5, pp. 305 – 308.

Huq, S., Rahman, A., Konate, M., Sokona, Y., Reid, H., 2003. Mainstreaming adaptation to climate change in least developed countries (LDCs). International Institute for Environment and Development (iied), Available at http://www.un.org/special-rep/ohrlls/ldc/LDCsreport.pdf

IAEA-Fact Sheets. Indicators for sustainable energy development. International Atomic Energy Agency (IAEA). http://www.iaea.org/Publications/Factsheets/English/indicators.pdf

IEA, 2005. Biofuels for transport: an international perspective. In-ternational Energy Agency (IEA) Available at http://www.ifri.org/files/Agriculture/FultontalkIFRI29March.pdf

IEA, 2007. IEA Energy Technology Essentials - Biofuel Produc-tion. International Energy Agency (IEA). Available at http://www.iea.org/techno/essentials2.pdf

ISO, 2006a. International Standard ISO 14040. Environmental management - Life cycle assessment - Principles and framework.

ISO, 2006b. International Standard ISO 14044. Environmental management - Life cycle assessment - Requirement and guide-lines

Kates, W.K., Parris, T.M., Leiserowitz, A.A., 2005. Environment: Science and Policy for Sustainable Development 47, pp. 8–21.

Khatiwada, D., 2007. A Comparative Environmental Life Cycle Assessment of Ethanol Blended (E10) and Conventional Petrol Fuel Car- A Case Study in Nepal. 14th LCA Case Studies Sympo-sium of ‘LCA of Energy - Energy in LCA’. Society of Environ-mental Toxicology and Chemistry (SETAC), Gothenburg, Swe-den.

Page 76: Dissertation on Sugar Production in Nepal

64

Khatiwada, D., and Silveira, S., 2009. Net energy balance of molas-ses based ethanol: the case of Nepal. Renewable and Sustainable Energy Reviews 13, 2515–2524.

Khatiwada, D., Silveira S., 2010. Greenhouse gas balances of mo-lasses based ethanol in Nepal (under review), International Jour-nal of Cleaner Production).

Kumar, S., Singh, N., Prasad, R., 2010. Anhydrous ethanol: A re-newable source of energy. Renewable and Sustainable Energy Reviews 14, 1830 – 1844

Macedo, I.C., Isaias, C., Seabra, J.E.A., Silva, J.E.A.R., 2008. Green house gases emissions in the production and use of ethanol from sugarcane in Brazil: the 2005/2006 averages and a prediction for 2020. Biomass Bioenergy 32, 582–95.

Naik, S.N., Goud, V.V., Rout, R.K., Dalai, A.K., 2010. Production of first and second generation biofuels: A comprehensive review, Renewable and Sustainable Energy Reviews 14, pp. 578–597.

Najafi, G., Ghobadian, B., Tavakoli, T., Yusaf, T., 2009. Potential of bioethanol production from agricultural wastes in Iran. Re-newable and Sustainable Energy Reviews 13, pp. 1418–1427

Nguyen, T. L.T., Gheewala, S.H., 2008a. Life cycle assessment of fuel ethanol from cane molasses in Thailand. Int J Life Cycle As-sess 13, 301–311

Nguyen, T.L.T., Gheewala, S.H., 2008c. Fuel ethanol from cane molasses in Thailand: Environmental and cost performance. En-ergy Policy 36, 1589–1599.

Nguyen, T.L.T., Gheewala, S.H., Garivait, S., 2007a. Full chain en-ergy analysis of fuel ethanol from cassava in Thailand. Environ Sci Technol 41, 4135–4142.

Nguyen, T.L.T., Gheewala, S.H., Garivait, S., 2007b. Fossil energy savings and GHG mitigation potentials of ethanol as a gasoline substitute in Thailand. Energy Policy 35, 5195–5205.

Nguyen, T.L.T., Gheewala, S.H., Garivait, S., 2007c. Energy bal-ance and GHG-abatement cost of cassava utilization for fuel eth-anol in Thailand. Energy Policy 35 , 4585-4596.

Nguyen, T.L.T., Gheewala, S.H., Garivait, S., 2008b. Full chain en-ergy analysis of fuel ethanol from cane molasses in Thailand. Ap-plied Energy 85, 722 – 734.

Nguyen, T.L.T., Gheewala, S.H., Sagisaka, M., 2010. Greenhouse gas savings potential of sugar cane bio-energy systems. Journal of Cleaner Production 18, 412–418.

Page 77: Dissertation on Sugar Production in Nepal

65

Nigam, P.S., Singh A., 2010. Production of liquid biofuels from renewable resources. Progress in Energy and Combustion Sci-ence, Article in Press, doi:10.1016/j.pecs.2010.01.003

Niven, R.K., 2005. Ethanol in gasoline: environmental impacts and sustainability review article. Renewable and Sustainable Energy Reviews 9, pp 535 – 555.

Pennington et al., 2004. Life cycle assessment Part 2: Current im-pact assessment practice. Environment International 30, pp. 721– 739.

Pennington, D., 2009. Bioenergy: Today & Tomorrow - Bringing Knowledge To Life! Michigan State University. Available at http://www.maes.msu.edu/upes/agtomm_2009/bioenergy.pdf

Phalan, B., 2009. The social and environmental impacts of biofuels in Asia: An overview. Applied Energy 86, S21–S29.Phalan (2009)

Pohit, S., Biswas, P.K., Kumar, R., Jha, J., 2009. International ex-periences of ethanol as transport fuel: Policy implications for In-dia. Energy policy 37, pp 5540 – 4548

Prakash, R., Henham, A., Bhat, I.K., 1998, Net energy and gross pollution from bio-ethanol production. Fuel 77, pp. 1629–1633

Rebitzer et al., 2004. Life cycle assessment Part 1: Framework, goal and scope definition, inventory analysis, and applications. Envi-ronment International 30, pp. 701– 720.

RFA, 2010. Ethanol industry outlook - climate of opportunity. Re-newable Fuels Association (RFA). Available at http://www.ethanolrfa.org/page/-/objects/pdf/outlook/RFAoutlook2010_fin.pdf?nocdn=1

Royal Society, 2008. Sustainable biofuels: prospects and challenges. Available at http://royalsociety.org/Sustainable-biofuels-prospects-and-challenges/

Schubert, R., Blasch, J., 2010. Sustainability standards for bioener-gy—A means to reduce climate change risks? Energy policy 38, pp. 2797–2805.

Shapouri, H., Duffield, J., McAloon, A., Wang, M., 2004. The 2001 net energy balance of corn ethanol. US Department of Agricul-ture. US.

Sheehan, J.J., 2009. Biofuels and the conundrum of sustainability, 20. pp 318–324.

Silveira, S., Khatiwada, D., 2010. Ethanol production and fuel sub-stitution in Nepal—Opportunity to promote sustainable devel-opment and climate change mitigation. Renewable and Sustaina-ble Energy Reviews 14, 1644–1652

Page 78: Dissertation on Sugar Production in Nepal

66

Smeets, E., Junginger, M., Faaij, A., Walter, A., Dolzan P., 2006.Sustainability of Brazilian bio-ethanol. Copernicus Institute – Department of Science, Technology and Society, Utrecht Uni-versity, the Netherlands. Report NWS-E-2006-110, ISBN 90-8672-012-9.

Smeets, S., Jungingera, M., Faaij, A., Walter, A., Dolzan, P., Tur-kenburg, W., 2008. The sustainability of Brazilian ethanol—an assessment of the possibilities of certified production. Biomass and bioenergy 32, 781 – 813.

Sorda, G., Banse, M., Kemfert, C., 2010. An overview of biofuel policies across the world. Energy policy (Article in Press), doi:10.1016/j.enpol.2010.06.066

UNCTAD, 2008. The least developed countries report 2008. Unit-ed Nations Conference on Trade and Development (UNCTAD).

UNCTAD, 2009. The least developed countries report 2009 - the state and development governance. United Nations Conference on Trade and Development (UNCTAD).

UNDESA, 2007. Small-scale production and use of liquid biofuels in Sub-Saharan Africa: Perspectives for sustainable development. United Nations Department of Economic and Social Affairs (UNDESA) commission on sustainable development: fifteen-session 30 April-11 May 2007, New York. Background paper no. 2. DESA/DSD/2007/2.

UNDP, 2006. Human Development Report - 2006. United Na-tions Development Program (UNDP).

UNESCAP, 2008. Energy Security and Sustainable Development in Asia and the Pacific. United Nations Economic and Social Commission for Asian and the Pacific (UNESCAP). Available at http://www.unescap.org/esd/energy/theme

UNIDO, 2006. Energy Security in Least Developed countries. United Nations Industrial Development Organization (UNIDO).

UNIDO, 2008. Powering Industrial Growth - the Challenge of Energy Security for Africa - Working paper, United Nations In-dustrial Development Organization (UNIDO).

UNMCLDC, 2007. Energizing the least developed countries to achieve the Millennium Development Goals: the challenges and opportunities of globalization issues. Making globalization work for the LDCs Istanbul; 9-11 July 2007. United Nations Ministeri-al Conference of the Least Developed Countries (UNMCLDC). Available at http://www.un.int/turkey/4.pdf

USEPA, 2006. Life cycle assessment: principles and practice. Na-tional Risk Maangment Research Laboratory, Office of Research

Page 79: Dissertation on Sugar Production in Nepal

67

and Development, U.S. Environmental Protection Agency (USEPA). Avaialble at http://www.epa.gov/nrmrl/lcaccess/pdfs/600r06060.pdf

Versteeg, S., 2007. Bioethanol production in Fiji: An environmen-tally sustainable project? Evidence Based Environmental Policy and Management 1: 82-106.

Walter, A., Ensinas A., 2010. Combined production of second-generation biofuels and electricity from sugarcane residues. En-ergy 35, pp. 874 - 879.

Wyman, C.E., 1994. Ethanol from lignocellulosic biomass: Tech-nology, economics, and opportunities. Bioresource Technology 50, pp.3-15.

Xunmin, Q., Xiliang, Z., Shiyan, C., Qingfang, G., 2009. Energy consumption and GHG emissions of six biofuel pathways by LCA in (the) People’s Republic of China. Applied Energy 86, 197–208.

Yan, J., Lin, T., 2009. Biofuels in Asia. Applied Energy 86 (edito-rial supplement), S1–S10.

Yan, X., Crookes, R.J., 2010. Energy demand and emissions from road transportation vehicles in China. Progress in Energy and Combustion Science, Article in press, doi:10.1016/j.pecs.2010.02.003

Zah, R., Faist, M., Reinhard, J., Birchmeier, D., 2009. Standardized and simplified life-cycle assessment (LCA) as a driver for more sustainable biofuels. Journal of cleaner production 17, S102–S105.

Zhou, A., Thomson, E., 2009. The development of biofuels in Asia. Applied Energy 86 (editorial supplement), S11–S20.

Zhou, Z., Jaing, H., Qin, L., 2007. Life cycle sustainability assess-ment of fuels. Fuel 86, pp. 256–263.