UNESCO Desire – Net project Wind Energy Luciano Pirazzi Enea – Renewable Sources and Innovative Energy Cycles [email protected].

UNESCO UNESCO Desire – Net projectDesire – Net project

Wind EnergyWind Energy

Luciano Pirazzi Luciano Pirazzi Enea – Renewable Sources and Innovative Energy CyclesEnea – Renewable Sources and Innovative Energy Cycles

[email protected]@casaccia.enea.it

Operational experience

Nowadays wind turbines are very reliable and perform with few operational difficulties. The average availability is generally over 98%. The availability of a wind turbine describes the amount of the time that it is actually functional, not out of order or being serviced.

The capacity factor, which is an index mainly dependent on the site characteristics, is ranging from 0.20 to 0.35, with higher values in Ireland and New Zealand, where capacity factors over 0.35, and in some areas exceeding 0.40, are quite frequent. The capacity factor is expressed by ratio between the net electricity generated, for the time considered, and the amount of energy that could have been generated at continuous full-power operation during the same period.

Operational experience

Wind turbines are designed with a life of 20 years or more. Danish studies have found that consumables such as gearbox oil and brake pads are often replaced at intervals of one to three years. Parts of the yaw system may be replaced every five years, and vital components exposed to fatigue loading, such as main bearings might be replaced once in the design light.

Selecting the right turbine

In order to select the right turbine the following factors should be taken into consideration:

• IEC Class of the site• Turbulence and spacing of turbines• Site area. How big is the site• Installed MW• Hub height and visual impact• Sound restrictions

•Real time data collection

• OPC client server

• Met Mast monitoring

• Historical Data Subsystem

• > SQL• > Report Engine

Supervisory Control And Data Acquisition (SCADA)

Economics

Wind energy prices:Wind energy prices are decreasing continuously. They fell by a factor of four from 1981 to 1996 Items included in energy price:Planning cost – capital cost of plant - construction costs – interest during construction – land costs – operating costs (O & M), including labour, materials, rents, taxes and insurance) - decommisioningValue of the global energy market in 2003 and 2004:8 billion Euros each year in 2005 > 11 billion eurosJob creation: about 200,000

Current plant costs Key factors

Installed costsTurbine pricesBalance of plant costs: foundation costs, electrical interconnection costs, access trackInstalled costs and wind speedsOperational costsSize of wind farmWind energy priceInfluence of wind speedNational wind energy prices

External costs

Hidden costs borne by governmentsCosts of damage caused to healthCost of global warming due to CO2 emissions

Future price trends

Trend towards larger wind turbinesFalling infrastructure costsReduction costs of raw materials?

Wind plant costs have been falling steadily and this trend is likely to continue

No single figure can be assigned to price of wind energy

On best sites, current wind prices are competitive with nuclear and gas plants

External costs of thermal plants need to be taken into account

Additional value of wind energy

Offshore wind energy prices are moving down too but not so rapidly

Costs of wind energy and other energy sources

$700/kW

$1000/kW

$1500/kW offshore

6 6,5 7 7,5 8 8,5 9site mean wind speed at hub hight m/s

0,02

0,03

0,04

0,05

0,06

0,07

0,08

0,09

0,1

0,11

0,12N

ucle

ar

Coa

l

Gas

$/kW

h

Wind energy

Source: EWEA, 2003

Calculated Costs per kWh Wind Power as a Function of a Wind Regime at a Chosen Site (Number of full Load Hours)

Technology

Coal Oil Gas Nuclear

Biomass

Ydro PV Wind

c€/kWh 215 311 13 0,20,7 0,083 0,031 0,6 0,050,25

External costs of electricity production in the EU countries

0,0002,0004,0006,0008,000

10,00012,00014,00016,00018,00020,000

Germ

any

18,4

28 M

W

Spain

10,02

7

USA 9,14

9

India

4,43

0

Denm

ark

3,12

2

Italy

1,71

8

UK 1,3

53

China

1,26

1

Japa

n 1,23

1

the

Nethe

rland

1,21

9

Portuga

l 1,02

2

Market Cumulative wind installed capacity at end 2005

WIND FORCE 12SUMMARY RESULTS IN 2020

Total MW installed 1,254,030Annual MW installed 158,728TWh generated to meet 12% global demand 3,054Co2 reduction (annual million tonnes) 1,832Co2 reduction (cumulative million tonnes) 10,771Total investment per annum €80 billionTotal job years 2.3 millionInstallation costs in 2020 €512/kWElectricity generation costs in 2020 €2.45cents/kWh

GWEC

GWECGWEC

GWEC

GWEC

GWEC

GWEC

Global Wind Power StatusCumulative MW by end of 2002 & Forecast 2007

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

Europe USA Asia Rest of World

2002 (32.037 MW) 2007 (83,317 MW)Source: BTM Consult ApS - March 2003

Wind Energy and the Environment

The large-scale use of renewable energy sources is essentialif the necessary reductions in CO2 and other emissionsfrom electricity generation are to be metand if sustainable development and sustainable growth are to be achieved.

Carbon dioxide savings and market development 2003-2020

(Wind Force 12 scenario)

Environmental benefits

Environmental pollution and the emission of CO2(carbon dioxide) from the use of fossil fuels constitutea threat to health, the environment and sustainableeconomic growth. Other major pollutantsfrom conventional electricity, which are avoidedthrough wind power, include SO2,NOx and PM10.

External costs

The environmental benefits associated with the generation of electricity from renewable energy, including wind power, can be quantified in economicterms. These benefits are not fully reflected in the market prices paid for wind generated electricity. Examples of external costs include effects on human health, damage to the environment, loss of amenity as well as economic effects such as payment of subsidies and employment benefits.

External costs

The most detailed analysis of external costs to datehas been carried out through the EuropeanCommission’s ExternE project.The ExternE report estimates that the cost of producingelectricity from coal or oil would double andthe cost of electricity production from gas wouldincrease by 30 %, if external costs, in the form ofdamage to the environment and health, were takeninto account.

Environmental impacts of wind energy

Visual impact: Wind turbines are a relatively new feature in the European countryside, and have an impact on amenity. Attitudes towards them willdepend on aesthetic judgements on beauty and diversity, which are subjective and with general reactions towards the technology. Consultation with, and acceptance by, local communities is essential, especially in rural areas where a particularly high value is placed on landscape amenity.

Sound emissions

Modern wind turbine designs have improved to the point where mechanical noise is insignificant, so the issue is now aerodynamic noise from the turning blades. At a distance of 300 metres from a 1 MW wind turbine, the expected sound level would be 45 decibels (dBA).

Noise level around a wind turbine

distance 500 m 300 m 250 m 200 m

660 kW turbine: 37.4 dBA 42.7 dBA 44.4 dBA 46.5 dBA1650 kW turbine:37.9 dBA 43.2 dBA 44.9 dBA 47.0 dBA

Birds

Collisions with turbines have been an issue at some older wind farm sites form the 1980s, especially the Altamont Pass in California – a result of poor siting, out-moded turbines and tower technology.Subsequent experiences in Germany and Denmark show that such effects can be avoided by responsible planning practice. Proper siting of turbines is important if adverse impacts are to be avoided.Wind-related avian collision fatalities represent 0.01 - 0.02%of annual avian fatalities in the US.

Construction

The construction process usually takes no more than a few weeks depending on the size of the project. Once complete, apart from access roads, agricultural activity can resume right up to the turbine bases of an operational wind farm.Between 1-3% of a wind farm area is utilized by turbines,so up to 99% of the land is available for other uses.

Energy balance

A 1997 study of a typical turbine bythe Danish Wind Industry Association shows that amodern wind turbine recovers all the energy inputsinvolved in its manufacture and operating life withinthree to four months – i.e. that over its 20 year lifetime,an average turbine will provide 63-78 timesmore energy than used to construct, operate andeventually dismantle the turbine.

Public acceptance

An analysis of public opinion surveys carried out in anumber of EU countries, including Spain, the UK, Denmark, Germany and Sweden shows substantial majorities in favour of developing wind energy, especially when compared with other fuel sources. The surveys also show that local approval rises once a windfarm starts operating. In some countries, direct involvement of the general public in wind energy projects has helped to encourage acceptance.

Market stimulation

• Policy 1. legislative measures and targets 2. capital cost and feed-in price incentives

• Environmental benefits

• Domestic and free resource

• Job creation

DIRECTIVE 2001/77/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL

of 27 September 2001 on the promotion of electricity produced from renewable energy sources in the

internal electricity market

National indicative targetsSupport schemesGuarantee of origin of electricity produced from renewableenergy sourcesAdministrative proceduresGrid system issuesSummary report

The Commission shall assess to what extent:

— Member States have made progress towards achieving theirnational indicative targets,

— the national indicative targets are consistent with the globalindicative target of 12 % of gross national energy consumptionby 2010 and in particular with the 22,1 % indicative share of electricity produced from renewable energy sources in total Community electricity consumption by 2010.

Wind power is now a mainstream option for electricity generation. “I recognize the importance of wind power,” said President George Bush on February 20, 2006. “It’s possible we could generate up to 20% of our electricity needs through wind.” Twenty percent is the share that nuclear power provides today. Wind energy development creates jobs, and will inject $4 billion worth of investment into the U.S. economy in 2006. In rural communities where wind projects are installed, farmers earn $2,000 to $4,000 or more per year per turbine installed on their land, while continuing to grow crops up to the foot of the turbines.

Legislative measures in the US supporting renewablesFederal Production Tax Credit

In 1992 the Energy Policy Act was signed into law and included enactment of a Production Tax Credit (PTC) under Section 45 of the Internal Revenue Code of 1986. This credit was available to corporate entities building new renewable energy production facilities such as solar, biomass, wood chip, geothermal, and wind electric power production plants. The tax credit at inception of the law was $0.015 per kilowatt hour (kWh) produced by the facility, increased each year by the official rate of inflation from the previous year, for the first ten years of operation of the equipment. The current PTC rate is approximately $0.019 per kWh.

The Renewables Portfolio Standard

The Renewables Portfolio Standard (RPS) is a flexible, market-driven policy that can ensure that the public benefits of wind, solar, biomass, and geothermal energy continue to be recognized as electricity markets become more competitive. The policy ensures that a minimum amount of renewable energy is included in the portfolio of electricity resources serving a state or country, and -- by increasing the required amount over time -- the RPS can put the electricity industry on a path toward increasing sustainability. Because it is a market standard, the RPS relies almost entirely on the private market for its implementation. Market implementation will result in competition, efficiency and innovation that will deliver renewable energy at the lowest possible cost.