NBSLM01E Climate Change and Energy: Past, Present and Future 2010 1.Introduction 2. Units and GDP Relationships 3.Definitions N.K. Tovey ( 杜杜杜 ) M.A, PhD, CEng, MICE, CEnv Н.К.Тови М.А., д-р технических наук Energy Science Director CRed Project 1
Dec 30, 2015
NBSLM01E Climate Change and Energy: Past, Present and Future
2010
1. Introduction
2. Units and GDP Relationships
3. Definitions
N.K. Tovey (杜伟贤 ) M.A, PhD, CEng, MICE, CEnv
Н.К.Тови М.А., д-р технических наук
Energy Science Director CRed Project
HSBC Director of Low Carbon Innovation1
Aim of Energy Section
• To review historic uses of Energy
• Provide basis for understanding Units and Definitions
• An overview of Global Energy Resources
• Barriers to Conservation
• Overview of Conservation Opportunities
• Brief Review of UK Energy Supply and Demand
• Issues of Electricity Supply and Fuel Mix
• An introduction to basic thermodynamics and opportunities arising from working with rather than against thermodynamics
• Energy Balance Tables
NBSLM01E Climate Change and Energy: Past, Present and Future
Some Administrative Matters
All the Handouts and other information, including these PowerPoint Presentations may be accessed from the
Energy Home Page (on the INTERNET)
www2.env.uea.ac.uk/gmmc/env/energy.htm
www2.env.uea.ac.uk/gmmc/env/energy.htm3
• In UK each person is consuming energy at a rate of
5kW
• In USA it is 10 kW
1/20th or World’s Population consumes 25% of all energy
• In Europe it is 5.7 kW
• Globally it is around 2kW
• ENERGY Consumption > Carbon Dioxide > Global Warming
1.1 INTRODUCTION
4
1.1 INTRODUCTION
0 1000 1500 2000 2500500
Year
En
ergy
Con
sum
pti
on
Nuclear Fusion ??
5
How much Carbon Dioxide is each person emitting as a result of the energy they use?
In UK 9 tonnes per annum.
What does 9 tonnes look like?
Equivalent of 5 Hot Air Balloons!
To combat Global Warming
we must reduce CO2 by 60%
i.e. to 2 Hot Air Balloons
How far does one have to drive to emit the same amount of CO2 as heating an old persons room for 1 hour?
1.6 miles
1.1 INTRODUCTION
6
ENERGY
PHYSICAL
TECHNICAL
ECONOMIC
ENVIRONMENTAL
SOCIAL
POLITICAL
Fuel Poverty Issues
UEA Heat Pump
7
Energy must be studied from a multi-disciplinary standpoint
Peter Chapman’s book – Fuel’s Paradise
• written in 1970s
• some figures are out of date
• concepts still relevant providing an alternative view on energy where the unit of currency is linked to the unit of energy
In 1974 Bramber Parish Council decided to go without street lighting for three days as a saving.
( this was during a critical power period during a Miner’s Strike).
Afterwards, the parish treasurer was pleased to announce that, as a result electricity to the value of £11.59 had been saved.
He added, however, that there was a bill of £18.48 for switching the electricity off and another of £12.00 for switching it on again.
It had cost the council £18.89 to spend three days in darkness.
An example of where saving resources and money are not the same
9
From the Independent
29th January 1996
similar warning have been issued in press for this winter
What is wrong with this title?
10
• No shortage of energy on the planet
• Potential shortage of energy in the form to which we have become accustomed.
Fossil fuels
• FUEL CRISIS.
1.2 THE ENERGY CRISIS - The Non-Existent Crisis
11
• ~ 15% of energy derived from food used to collect more food to sustain life.
+ energy used for
making clothing, tools, shelter
• Early forms of non-human power:-
• 1) fire
• 2) animal power
1.3 HISTORICAL USE OF ENERGY up to 1800
• OTHER ENERGY FORMS HARNESSED
1) Turnstile type windmills of Persians
2) Various water wheels (7000+ in UK by 1085)
3) Steam engines (?? 2nd century AD by Hero)
4) Tidal Mills (e.g. Woodbridge, Suffolk 12th Century)
12
LONDON - late 13th /early 14th Century
Shortage of timber for fires in London Area
Import of coal from Newcastle by sea for poor
Major environmental problems -high sulphur content of coal
Crisis resolved - The Black Death.
1.4 The First Fuel Crisis
13
UK - Late 15th/early 16th century
Shortage of timber - prior claim for use in ship-
building
Use of coal became widespread -even eventually for
rich
Chimneys appeared to combat problems of smoke
Environmental lobbies against use
Interruption of supplies - miner's strike
Major problems in metal industries led to many patents
to produce coke from coal (9 in 1633 alone)
1.5 The Second Fuel Crisis:-
14
Problems in Draining Coal Mines and Transport of coal
> threatened a third Fuel Crisis in Middle/late 18th Century
Overcome by Technology and the invention of the steam engine by Newcommen.
a means of providing substantial quantities of mechanical power which was not site specific (as was water power etc.).
NEWCOMMEN's Pumping Engine was only 0.25% efficient
1.6 Problems in Draining Coal Mines
WATT improved the efficiency to 1.0%
15
Current STEAM turbines achieve 40% efficiency,
1.6 Current Limitations
further improvements are
• LIMITED PRIMARILY BY PHYSICAL LAWS
• NOT BY OUR TECHNICAL INABILITY TO DESIGN AND BUILD THE PERFECT MACHINE.
Coal fired power stations: ultimate efficiency ~ 45%
even with IGCC
CCGT Stations are currently 47-51% efficient > ultimately ~ 55%.
16
• Explosive sports - e.g. weight lifting
500 W for fraction of second
• Sustained output of fit athlete --> 100 - 200 W
• Normal mechanical energy output << 50 W
• Heat is generated by body to sustain body at pre-determined temperature:-
Thermal Comfort
• approx.: 50 W per sq. metre of body area when seated
• 80 W per sq. metre of body area when standing.
1.7 Energy Capabilities of Man
17
Early Wind Power Devices
C 700 AD in Persia
•used for grinding corn
•pumping water
•evidence suggests that dry valleys were “Dammed” to harvest wind
18
NUCLEAR
CHEMICAL - fuels:- gas, coal, oil etc.
MECHANICAL - potential and kinetic
ELECTRICAL
HEAT - high temperature for processes
- low temperature for space heating
• All forms of Energy may be measured in terms of Joules (J),
• BUT SOME FORMS OF ENERGY ARE MORE EQUAL THAN OTHERS
1.8 Forms of Energy
19
Energy does not usually come in the form needed:
convert it into a more useful form.
All conversion of energy involve some inefficiency:-
Physical Constraints (Laws of Thermodynamics)
can be very restrictive
MASSIVE ENERGY WASTE.
This is nothing to do with our technical incompetence. The losses here are frequently in excess of 40%
1.9 ENERGY CONVERSION
20
Technical Limitations
(e.g. friction, aero-dynamic drag in turbines etc.) can be improved, but losses here are usually less than 20%, and in many cases around 5%.
Some forms of energy have low physical constraints converted into another form with high efficiency (>90%).
e.g. mechanical <--------> electrical mechanical/electrical/chemical -----------> heat
Other forms can only be converted at low efficiency
e.g. heat ------------> mechanical power - the car!
or in a power station
1.9 ENERGY CONVERSION
21
USE MOST APPROPRIATE FORM OF ENERGY FOR NEED IN HAND. • e.g. AVOID using ELECTRICITY for• LOW TEMPERATURE SPACE heating• Hot Water Heating
in UK, Germany, India, China
but using electricity in Norway, Canada. Colombia, France is sensible
• Cooking (unless it is in a MicroWave).
1.9 ENERGY CONVERSION
22
HEATING - space and hot water demand
(80%+ of domestic use excluding transport)
LIGHTING
COOKING
ENTERTAINMENT
REFRIGERATION
TRANSPORT
INDUSTRY
- process heating/ drying/ mechanical power
• IT IS INAPPROPRIATE TO USE
ELECTRICITY FOR SPACE HEATING
1.10 WHAT DO WE NEED ENERGY FOR?
23
HIGH GRADE:
- Chemical, Electrical, Mechanical
MEDIUM GRADE: - High Temperature Heat
LOW GRADE: - Low Temperature Heat
• All forms of Energy will eventually degenerate to Low Grade Heat
• May be physically (and technically) of little practical use - i.e. we cannot REUSE energy which has been degraded
- except via a Heat Pump.
1.11 GRADES OF ENERGY
24
Energy Conservation is primarily concerned with MINIMISING the degradation of the GRADE of ENERGY.
(i.e. use HIGH GRADE forms wisely
- not for low temperature heating!!).
To a limited extent LOW GRADE THERMAL ENERGY may be increased moderately in GRADE to Higher Temperature Heat using a HEAT PUMP.
However, unlike the recycling of resources like glass, metals etc., where, in theory, no new resource is needed, we must expend some extra energy to enhance the GRADE of ENERGY.
1.12 ENERGY CONSERVATION
25
NBSLM01E Climate Change and Energy: Past, Present and Future
2010
2. Units and GDP Relationships
N.K. Tovey (杜伟贤 ) M.A, PhD, CEng, MICE, CEnv
Н.К.Тови М.А., д-р технических наук
Energy Science Director CRed Project
HSBC Director of Low Carbon Innovation26
2.0 UNITS of Energy: INTRODUCTION
• How much Energy is there in different fuels?
MegaJoules Yogurts kWh
Yogurt 85000 calories (85kcal)
0.365 1 0.1
1 cubic meter gas 39.6 106.8 10.8
1 litre petrol 32.9 90.1 9.1
1 litre diesel 35.7 97.8 9.9
1 litre LPG 25.0 68.6 7.0
1 litre heating oil 35.3 96.6 9.8
• How much CO2 is given of by different fuels ?MJ kg CO2 CO2 to provide 1
kWh of useful heat
Gas 39.6 MJ/m3 2.035 kg/m3 0.21 – 0.26 kg
Petrol 32.9 MJ/litre 2.315 kg/litre
Diesel 35.7 MJ/litre 2.630 kg/litre
LPG 25.0 MJ/litre 1.495 kg/litre 0.24 - 0.31 kg
Heating oil 35.3 MJ/litre 2.518 kg/litre 0.27 – 0.35 kg
Electricity 0.54 kg
Electricity (Heat Pump) 0.12 – 0.18 kg
Figures in RED assume heating is provided by condensing appliances
•A litre of diesel has 8.6% more energy than 1 litre of petrol
•How far does one have to drive in a small family car to emit as much CO2 as heating and old persons room for 1 hour?
1.6 miles 28
2.0 UNITS of Energy: INTRODUCTION
The study of ENERGY is complicated by the presence of numerous sets of UNITS OF MEASURE which frequently confuse the issue.
It is IMPORTANT to recognise the DIFFERENCE between the TWO BASIC UNITS:-
a) the JOULE (a measure of quantity)
b) the WATT (a RATE of acquiring/ converting/ or using ENERGY).
2.0 UNITS of Energy: INTRODUCTION
29
The basic unit of Energy is the JOULE.
the WORK DONE when a force moves through a distance of 1 metre in the direction of the force. The SI unit is the JOULE, and all forms of Energy should be measured in terms of the JOULE.
FORCE is measured in Newtons (N)DISTANCE is measured in metres (m)
Thus WORK DONE = Newtons x metres = Joules.
A 1 kg lump of coal, or a litre of oil will have an equivalent Energy Content measured in Joules (J).
Thus 1 kg of UK coal is equivalent to 24 x 106 J.or 1 litre of oil is equivalent to 42 x 106 J.
The different units currently in use are shown in Table 2.1
2.1 Quantity of Energy
30
JOULE (J). calorie (cal) erg Kalorie (or kilogram calorie Kcal or Kal) British Thermal Unit (BTU) Therm kilowatt-hour (kWh) million tonnes of coal equivalent (mtce) million tonnes of oil equivalent (mtoe) - (often also seen as - mtep - in International Literature). litres of oil gallons (both Imperial and US) of oil barrels of oil million tonnes of peat equivalent
Table 2.1 Energy units in common use.
2.1. QUANTITY OF ENERGY
31
Situation is confused further• US (short) ton • Imperial (long) ton • metric tonne.
European Coal has an Energy content 20% than the equivalent weight of UK coal.
See Data Book for conversion factors.
Always use the SI unit (JOULE) in all essays etc. If necessary cross refer to the original source unit in brackets.
CONSIDERABLE CONFUSION SURROUNDS THE USE OF THE KILOWATT-HOUR -- DO NOT USE IT!!!!
2.1. QUANTITY OF ENERGY
32
The RATE of doing WORK, using ENERGY is measured in WATTS.
i.e. 1 Watt = 1 Joule per second 1 W = 1 J s-1
Burn 1 kg coal (Energy Content 24 x 106 J) in 1 hour (3600 seconds) – RATE of consumption is:-
24 x 106 / 3600 = 6666.7 W
Equally, a Solar Panel receiving 115 W m-2 (the mean value for the UK), the total energy received in the year will be:-
115 x 24 x 60 x 60 x 365 = 3.62 x 109 J.
2.2. RATE OF USING ENERGY
33
NOTE: THE UNITS:-
KILOWATTS per HOUR
KILOWATTS per YEAR
KILOWATTS per SECOND
are MEANINGLESS (except in very special circumstances).
WARNING: DO NOT SHOW YOUR IGNORANCE IN EXAM QUESTIONS BY USING SUCH UNITS
2.2. RATE OF USING ENERGY
34
Implies that the cost of Sizewell would be about £15!!!!!!!
35
milli - m x 10-3
kilo - k x 103
Mega - M x 106
Giga - G x 109
Tera - T x 1012
Peta - P x 1015
Exa - E x 1018
NOTE:-
1) The prefix for kilo is k NOT K2) There are no agreed prefixes for 1021 or 1024
3) Avoid mixing prefixes and powers of 10 wherever possible.
i.e. 280 GJ is permissible but not 28000 GJ or 2.8 x 10 4 GJ.
2.3. SI PREFIXES
36
0 5 10 15 20 25 30
kW per Head
0
5000
10000
15000
20000
25000
30000
35000
40000
GD
P p
er h
ead
(U
S$
(95)
USA
Russia
Canada
China
India
UK
Japan
Germany
Poland
France
Qatar
Other EU Countries
Nordic EU New EU
Mediterranean EU
The wealth of a country and energy requirements are related
Energy – GDP Relationships
Energy – GDP relationships• As an exercise in unit conversion download the energy-
GDP relationships file from the Web Page.• Convert the units of thousand tonnes of oil equivalent into
PetaJoules.• Work out the energy requirement associated with £1 of
GDP.• Plot the relationship with time - How has this changed
over the last 60 years?• Noting the energy requirement for £1 wealth, estimate
what the price of petrol and diesel should be if society valued energy at the same level as wealth generally if the energy content of a litre of petrol is 32.9 MJ/litre and that of diesel is 35.7 MJ/litre
• As an exercise in your own time – repeat the analysis for each of the fuels Coal, Gas, Oil, Electricity separately.
NBSLM01E Climate Change and Energy: Past, Present and Future
2010
3. Energy Definitions
N.K. Tovey (杜伟贤 ) M.A, PhD, CEng, MICE, CEnv
Н.К.Тови М.А., д-р технических наук
Energy Science Director CRed Project
HSBC Director of Low Carbon Innovation39
All uses of energy involve conversion of one form of energy to another.
Energy conversion processes is inherently inefficient
3. ENERGY - DEFINITIONS
the amount of useful energy outEfficiency () = ----------------------------------------- x 100% the amount of energy put in
Some Typical Efficiencies:-
steam (railway) engines 10% cars 20 - 25% electric fire ~100%gas central heating boiler 70 - 75%oil central heating boiler 65 - 70%
UEA boiler ~87%Power Station Boiler 90-92%Open Coal fire 10%Coal Central Heating 40-50% Steam Turbine 45-50%
40
3.2 PRIMARY ENERGY -
The energy content of the energy resource when it is in the ground.
3.3 DELIVERED ENERGY -
The energy content of the fuel as it is delivered to the place of use.
3.4 USEFUL ENERGY -
The actual amount of energy required for a given function IN THE FORM USABLE FOR THAT FUNCTION.
ENERGY DEFINITIONS
41
Primary Energy Content of fuel PER = ------------------------------------------ Delivered Energy content of fuel
EXAMPLES:-
Gas - 1.06 : Oil - 1.08 : Coal - 1.02 --------------------------------------e.g. for gas, 6% of the energy extracted is used either directly, or indirectly to deliver the energy to the customer.
- exploration - making production platforms - making pipelines - pumping - administration and retail of fuel - fractionating/blending fuel
3.5 PRIMARY ENERGY RATIO (PER)
For Electricity, the PER has varied over the years - it is currently around 2.80
42
Appliances are not, in general 100% efficient in converting the fuel into a useful form of energy.
Thus (from 3.1 above):-
The efficiency of the appliance may be expressed as:-
useful energy out (in form required) = ------------------------------------------------ energy input to appliance (+) + in most cases, the energy input will be the delivered energy, so:-
useful energy = ------------------------------- delivered energy
3.6 Appliance Efficiency ()
43
Life Cycle Analysis
• If we want 1 GJ of useful energy, • How much energy must we dig from the ground if we require the energy as heat from as gas boiler with an efficiency of 70%?
Primary Energy Required = 1 / 0.7 x 1.06 = 1.51 GJ =======
Be sure you understand this relationship, and why it is not:-
0.7 x 1.06
or 1.3 x 1.06
3.7 FURTHER COMMENTS ABOUT EFFICIENCY
44
Energy Efficiency is the efficient use of energy.
IT DOES NOT NECESSARILY MEAN A SAVING OFRESOURCES.
e.g.Producing 20% more products for same energy input would not save energy overall even though it would reduce energy requirement per product.
Insulating a poorly heated house will increase the efficiency of using energy, but the savings in resources will be small
increased temperature avoiding hypothermia is efficient use of energy.
3.8 ENERGY EFFICIENCY
45
Energy Conservation is the saving of energy resources.
Energy Efficiency is a necessary pre-requisite for Energy Conservation
(remember Energy Efficiency does not necessarily mean Energy Conservation).
It is interesting to note the Government Office was termed
THE ENERGY EFFICIENCY OFFICE
Some members of the Government still believe Energy Efficiency and Energy Conservation are the same.
However, the ENERGY SAVING TRUST (relevant for domestic applications is closer to what is needed. The CARBON TRUST is the equivalent organisation for businesses
3.9 ENERGY CONSERVATION
46
Industry/Commerce often consider Energy Conservation only as a saving in MONETARY terms
The moral definition is the saving of resources. This often will not result in a MONETARY saving
The so called Energy Conservation Grants to Industry in late 1970's early 1980's were not Conservation Grants at all, but Grants to encourage switching of fuels from oil to coal.
3.10 OTHER DEFINITIONS OF ENERGY CONSERVATION
47
Energy Content of the fuel per unit mass or unit volume.
- maximum amount of energy that can be extracted from a unit of the fuel.
There are two Calorific Values:-
lower calorific value (LCV)
This is amount of energy derived by combusting a fuel when the products of combustion are emitted at temperatures in excess of 100oC i.e. any water present is emitted as steam.
upper calorific value (UCV)
This is amount of energy derived by combusting a fuel when the products of combustion are emitted at temperatures below 100oC i.e. any water present is emitted as water vapour.
The difference between the two calorific values is about 5% (UCV > LCV)
3.11 CALORIFIC VALUE
48
This is the Energy required to raise the temperature of 1 kg of a body through 1 degree Celsius.
This parameter is needed when storage of Energy is considered. (e.g. size of Hot Water Cylinder in a House)
3.12 SPECIFIC HEAT
49
50
This is the Energy required to raise the temperature of 1 kg of a body through 1 degree Celsius.
This parameter is needed when storage of Energy is considered. (e.g. size of Hot Water Cylinder in a House)
3.12 SPECIFIC HEAT
51
Finally a point for reflection
52
1.33 billion people
0.94 billion people
Raw materials
1.03 billion people
Products: 478 M
tonnes CO 2
increase (2002-05)
Aid &
Education
The Unbalanced Triangular Trade
Each person in Developed Countries has been responsible for an extra 463 kg of CO2 emissions in goods imported from China in just 3 years (2002 – 2005)
53
And Finally
Lao Tzu (604-531 BC) Chinese Artist and Taoist philosopher 老子 ( 604-531BC )中国古代思想家、哲学家
“If you do not change direction, you may end up where you are heading.” (直译):“如果你不改变,你将止步于原地。”
N.K. Tovey (杜伟贤 ) M.A, PhD, CEng, MICE, CEnv