1 recipient of james watt gold medal aramco: science pathway: 8th july 2013 the energy trilema: the...
TRANSCRIPT
1
Recipient of James Watt Gold Medal
ARAMCO: Science Pathway: 8th July 2013
The Energy Trilema: The Triple Challenges of Carbon Reduction, Energy Security
and Cost of our Future Energy Supplies
Keith Tovey ( 杜伟贤 ) M.A., PhD, CEng, MICE, CEnv Reader Emeritus: University of East AngliaН.К.Тови
Energy is a key driver for Modern Economies
However, energy production, generation and use is having an impact on the Climate.
•Brief Review of Climate Change Issues
•Overview of Energy Supply and Demand and consequential CO2 issues
•Energy Security Issues – particularly for the UK
including Renewable Energy Options for a Sustainable Future
•Technical options to reduce demand
•Reducing Demand and Carbon Emissions and saving money through Awareness and good Management
•Conclusions
2
Overview of oil, gas and alternative energy industry in the UK and Low Carbon options for the future
3
Increasing Occurrence of Drought
3
4
Increasing Occurrence of Flood
4
5
Arctic Sea Ice Cover 1979 - 2012
• Minimum Summer Sea Ice in 1979 ~ 7.01 million sq km• Red line outlines extent for reference• Minimum Summer Sea Ice in 2012 ~ 3.44 million sq km a loss of 51% in 33 years• Significantly lower in 2012 than average minimum• Source http://www.nasa.gov/topics/earth/features/2012-seaicemin.html
Is Global Warming natural or man-made?
Natural causes• Earth’s Orbit• Sunspot Activity• Volcanic Eruptions • Etc.
Reasonable agreement up to ~ 1960
Man-made causes do not show particularly good agreement in early part of period.
BUT including both man- made and natural gives good agreement
6
Temperature variations in last 160 years
www.nasa.gov/home/hqnews/.../HQ_11-014_Warmest_Year.htm
7
• Brief Review of Climate Change Issues
• Overview of Energy Demand and consequential CO2
issues
• Energy Security Issues – particularly for the UK
including Renewable Energy Options for a Sustainable Future
• Technical options to reduce demand
• Reducing Demand and Carbon Emissions and saving money through Awareness and good Management
• Conclusions
8
Overview of oil, gas and alternative energy industry in the UK and Low Carbon options for the future
9Per capita Carbon Emissions (tonnes per capita)
How do UK and Saudi Arabia compare with other countries?
Why do some countries emit more CO2 than others?
What is the magnitude of the CO2 problem?
9
UKFrance
World Average
Saudi Arabia
10
How does electricity consumption vary between countries?
• Why do very similar countries (e.g. Norway and Sweden) have very different levels of consumption?
• What environmental impact might these differences have?
11
Conventional Generation of Electricity
Diagram illustrates situation with conventional generation using coal, oil, gas or nuclear
Overall efficiency ~ 35%
Largest loss in Power Station
1.0 Unit
12
Fossil Fuel Options for Electricity Generation
BoilerHP
Generator
Pump
Fuel InCoal/Oil/Gas/
Nuclear
Schematic of a conventional coal, gas, oil or nuclear power plantTypical Maximum Efficiency for coal/oil/gas ~ 38 - 39%with super critical steam conditions ~ 42 – 45%Nuclear Efficiencies ~ 30 – 34% for PWR or 38 – 40% for AGR
High and Low Pressure Turbines
LP
Superheated Steam 563oC 160 bar
Steam at ~ 0.03 bar
CondenserElectricity In
13
Fossil Fuel Options for Electricity Generation
BoilerHP
Generator
Pump
Fuel InCoal/Oil/Gas/
Nuclear
Schematic of a conventional coal, gas, oil or nuclear power plantTypical Maximum Efficiency for coal/oil/gas ~ 38 - 39%with super critical steam conditions ~ 42 – 45%Nuclear Efficiencies ~ 30 – 34% for PWR or 38 – 40% for AGR
High and Low Pressure Turbines
LP
Superheated Steam 563oC 160 bar
Steam at ~ 0.03 bar
CondenserElectricity In
Why do we condense the steam to water only to heat it up again?.
Does this not waste energy?
NO!!
Thermodynamics is the key
14
Chemical or Nuclear
EnergyCoal / Oil / Gas/Nuclear
Electrical Energy Out
Heat Energy
Boiler
Turbine
GeneratorMechanical Energy
Electricity used in Station
Power Station
100 units
38 units
90 units
3 units
90%
95%
48%
41 units
Conventional Electricity Power Station
15
Elementary Thermodynamics - History.
Newcomen Engine
pushes piston up
3) At end of stroke, close steam value open injection valve
(and pumping rod down)
4) Water sprays in condenses steam in cylinder creating a vacuum and sucks piston down - and pumping rod up
2) Open steam valve
1) Boil Water > SteamProblem:
Cylinder continually is cooled and heated.
15
16 Watt Engine
1) Cylinder is always warm
2) cold water is injected into condenser
3) vacuum is maintained in condenser so “suck” out exhaust steam.
4) steam pushes piston down pulling up pumping rod.
Higher pressure steam used in pumping part of cycle.
16
Elementary Thermodynamics – Watt Engine
17
Thermodynamics is a subject involving logical reasoning.
Much of it was developed by intuitive reasoning.
• 1825 - 2nd Law of Thermodynamics - Carnot
• 1849 - 1st Law of Thermodynamics - Joule
• Zeroth Law - more fundamental - a statement about measurement of temperature
• Third Law - of limited relevance for this Session
17
Elementary Thermodynamics - History.
•The Newcomen Engine was 0.25% efficient•The Watt Engine was 1% efficient
18
Carnot’s reasoning
Water at top has potential energy
Water at bottom has lost potential energy but gained kinetic energy
18
Elementary Thermodynamics – 2nd Law.
19
Carnot’s reasoning
Water looses potential energy
Part is converted into rotational energy of wheel
Potential Energy = mgh
• Theoretical Energy Available = m g (H1 - H2)
• Practically we can achieve 85 - 90% of this
H1
H2
19
Elementary Thermodynamics – 2nd Law.
20
Carnot’s reasoningTemperature is analogous to Head of Water
• Energy out Temperature Difference
• Energy out (T1 - T2)
• T1 is inlet temperature
• T2 is outlet temperature
Carnot Efficiency
But temperatures must be in Kelvin
i.e. Degrees Celcius + 273
20
Elementary Thermodynamics – 2nd Law.
1
21
T
TT
inputyouwhat
outgetyouwhat
Schematic Representation
of a Power Station
Heat In Q1
Heat Out Q2
Work Out
W
Heat Engine
The Carnot efficiency is the theoretical efficiency, practical issues such as friction, windage losses in the turbine and heat losses from the casing reduce this to around 75% of the theoretical value.
so overall efficiency in power station:-
Boiler xEfficiency
90%
21
Power Station Efficiency
1
21
T
TT
Practical x Efficiency
~75%
Generator xEfficiency
95%
Carnot xEfficiency
Depends on temperatures
Station UseEfficiency
94%
=
How will efficiency of power station vary:• from summer to winter in UK?• in Saudi Arabia?• if new generation super critical steam station are built?
Boiler xEfficiency
90%
22
Examples of Power Station Efficiency
Practical x Efficiency
~75%
Generator xEfficiency
95%
Carnot xEfficiency
Station UseEfficiency
94%
=
Working in 5 Groups with each Group taking a separate task work out the station efficiencies using the standard formula:
1
21
T
TT
• T1 is ~565 oC in a conventional steam stations and ~ 650 oC in a super critical steam station.
• Effective T2 is about 10 oC warmer than relevant ambient temperature.
• Remember to add 273 to convert to degrees Kelvin!!Group T1 Ambient Temp Efficiency
1 UK Winter 565 oC 8 oC
2 UK Summer 565 oC 18 oC
3 Saudi Arabia Winter 565 oC 15 oC
4 Saudi Arabia Summer 565 oC 35 oC
5 Super Critical UK Winter 650 oC 8 oC
23
Combined Cycle Gas Turbine for Electricity Generation
HP LP
Generator
CondenserPump
Generator
C T
Air
Combustion
Gas
Exhaust
C – CompressorT – TurbineWHB – WasteHeat Boiler Efficiency 47 – 56%
WHB
Approximate Carbon Emission factors during electricity generation including fuel extraction, fabrication and transport.
24
Impact of Electricity Generation on Carbon Emissions.
Fuel Approximate emission factor
per kWh
Comments
Coal ~900 – 1000g Depending on grade and efficiency of power station
Oil ~800-900 Depending on grade and efficiency of power station
Gas (Steam) ~600g Conventional Steam Station
Gas (CCGT) ~400g Most modern may be as low as 380g
Nuclear 5 – 10g Depending on reactor type
Renewables ~ 0 For wind, PV, hydro
• Transmission/Distribution losses • UK ~ 8%: Saudi Arabia 9%: India ~ 24%
Overall UK ~530gVaries on hour by hour basis depending on generation mix
25
CO2 Emissions and Electricity (kg/kWh)
25
France
UK
Saudi Arabia
Overall: UK ~500 gm/kWh: France ~80 gm/kWh Saudi Arabia ~700 gm/kWh
World Average 0.550
Saudi Arabia
26
Electricity Generation Mix in selected Countries
26
Coal
Oil
Gas
Nuclear
Hydro/ Tidal/Wave
Other Renewables
Biofuels/Waste
• Brief Review of Climate Change Issues
• Overview of Energy Demand and consequential CO2
issues
• Energy Security Issues – particularly for the UK
including Renewable Energy Options for a Sustainable Future
• Technical options to reduce demand
• Reducing Demand and Carbon Emissions and saving money through Awareness and good Management
• Conclusions
27
Overview of oil, gas and alternative energy industry in the UK and Low Carbon options for the future
28
Energy Security is a potentially critical issue for the UKUntil 2004, the UK was a net exporter of gas.
Currently only 50% now provided by UK sources.
Import Gap
In early March 2013, technical issues with pipe line from Norway and restrictions on LNG imports made UK gas supply tight.
In late March things became even more critical with less than 1 days supply available.
Reduction because of switch back to coal
29
Options for Electricity Generation in 2020 - Non-Renewable Methods
Potential contribution to electricity supply in 2020 and drivers/barriers
Energy Review
2002
9th May 2011 (*)
Gas CCGT0 - 80% (at present 45-
50%)Available now (but gas
is running out)~2p +
8.0p[5 - 11]
* Energy Review 2011 – Climate Change Committee May 2011
?
Carbon sequestration either by burying it or using methanolisation to create a new transport fuel will not be available at scale required until mid 2020s if then
30
Options for Electricity Generation in 2020 - Non-Renewable Methods
Potential contribution to electricity supply in 2020 and drivers/barriers
Energy Review
2002
9th May 2011 (*)
Gas CCGT0 - 80% (at present 45-
50%)Available now (but gas
is running out)~2p +
8.0p[5 - 11]
nuclear fission (long term)
0 - 15% (France 80%) - (currently 18% and
falling)
new inherently safe designs - some
development needed2.5 - 3.5p
7.75p [5.5 - 10]
nuclear fusion unavailablenot available until 2040 at earliest not until
2050 for significant impact
"Clean Coal"Coal currently ~40% but
scheduled to fall
Available now: Not viable without Carbon
Capture & Sequestration
2.5 - 3.5p
[7.5 - 15]p - unlikely
before 2025
* Energy Review 2011 – Climate Change Committee May 2011
0
2000
4000
6000
8000
10000
12000
14000
1950 1960 1970 1980 1990 2000 2010 2020 2030 2040
In
sta
lled
Ca
pacit
y (
MW
)
New Build ?
ProjectedActual
Nuclear New Build assumes one new station is completed each year after 2020.
?
31
Options for Electricity Generation in 2020 - Renewable
Future prices from
* Renewable Energy Review – 9th May 2011 Climate Change Committee
1.5MW TurbineAt peak output provides sufficient electricity for 3000 homes – operating for 12 years
On average has provided electricity for 700 – 850 homes depending on year
~8.2p +/- 0.8p
Potential contribution to electricity supply in 2020 and
drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p) *
On Shore Wind ~20% [~15000 x 3 MW turbines]
available now for commercial exploitation ~ 2+p
32
Options for Electricity Generation in 2020 - Renewable
~8.2p +/- 0.8p
Potential contribution to electricity supply in 2020 and
drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p) *
On Shore Wind ~20% [~15000 x 3 MW turbines]
available now for commercial exploitation ~ 2+p
Scroby Sands has a Load factor of 28.8% - 30% but nevertheless produced sufficient electricity on average for 2/3rds of demand of houses in Norwich. At Peak time sufficient for all houses in Norwich and Ipswich
Climate Change Committee (9th May 2011) see offshore wind as being very expensive and recommends reducing planned expansion by 3 GW and increasing onshore wind by same amount
Off Shore Wind 20 - 40%some technical
development needed to reduce costs.
~2.5 - 3p 12.5p +/- 2.5
33
Options for Electricity Generation in 2020 - Renewable
~8.2p +/- 0.8p
Potential contribution to electricity supply in 2020 and
drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p) *
On Shore Wind ~20% [~15000 x 3 MW turbines]
available now for commercial exploitation ~ 2+p
Off Shore Wind 20 - 40%some technical
development needed to reduce costs.
~2.5 - 3p 12.5p +/- 2.5
Micro Hydro Scheme operating on Siphon Principle installed at
Itteringham Mill, Norfolk.
Rated capacity 5.5 kW
Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Hydro (mini - micro)
5%technically mature, but
limited potential2.5 - 3p
11p for <2MW projects
34
Options for Electricity Generation in 2020 - Renewable
~8.2p +/- 0.8p
Potential contribution to electricity supply in 2020 and
drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p) *
On Shore Wind ~20% [~15000 x 3 MW turbines]
available now for commercial exploitation ~ 2+p
Off Shore Wind 20 - 40%some technical
development needed to reduce costs.
~2.5 - 3p 12.5p +/- 2.5
Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Hydro (mini - micro)
5%technically mature, but
limited potential2.5 - 3p
11p for <2MW projects
Climate Change Report suggests that 1.6 TWh (0.4%) might be achieved by 2020 which is equivalent to ~ 2.0 GW.
Photovoltaic<<5% even
assuming 10 GW of installation
available, but much further research needed to bring down
costs significantly15+ p
25p +/-8 13-15p (2012 projection)
35
Options for Renewable Electricity Generation in 2020 in desert climates
but not in UK
Central Solar Power Plants in SpainIn foreground PS10 – 11 MW – in background PS20 – 20 MW
A 500 MW plant is due for completion in 2013 at Crescent Dunes in USA
36
Integrated Solar Combined Cycle Plant
CondenserPump
HP LPC T
Air
Combustion
Gas
Exhaust
GG
C – CompressorT – TurbineG – GeneratorWHB – Waste Heat Boiler
WHB
Parabolic Solar Power Plant
Example: Hassi R’Mel , Algeria 25 MW Solar & 130 MW Combined Cycle
37
Options for Electricity Generation in 2020 - Renewable
~8.2p +/- 0.8p
Potential contribution to electricity supply in 2020 and
drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p) *
On Shore Wind ~20% [~15000 x 3 MW turbines]
available now for commercial exploitation ~ 2+p
Off Shore Wind 20 - 40%some technical
development needed to reduce costs.
~2.5 - 3p 12.5p +/- 2.5
Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Hydro (mini - micro)
5%technically mature, but
limited potential2.5 - 3p
11p for <2MW projects
Photovoltaic<<5% even assuming
10 GW of installation
available, but much further research needed to bring down costs significantly
15+ p 25p +/-8
Transport Fuels:
• Biodiesel?
• Bioethanol?
• Compressed gas from methane from waste.
To provide 5% of UK electricity needs will require an area the size of Norfolk and Suffolk devoted solely to biomass
Sewage, Landfill, Energy Crops/ Biomass/Biogas
??5% available, but research needed in some areas e.g. advanced gasification
2.5 - 4p7 - 13p
depending on technology
38
Options for Electricity Generation in 2020 - Renewable
Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Potential contribution to electricity supply in 2020 and drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p)
On Shore Wind
~20% available now ~ 2+p ~8.2p +/- 0.8p
Off Shore Wind
20 - 40%available but costly
~2.5 - 3p 12.5p +/- 2.5
Small Hydro 5% limited potential 2.5 - 3p11p for <2MW projects
Photovoltaic <<5% available, but very
costly15+ p 25p +/-8
Biomass ??5% available, but research
needed 2.5 - 4p 7 - 13p
Wave/Tidal Stream
currently < 10 MW may be
1000 - 2000 MW (~0.1%)
technology limited - major development not
before 20204 - 8p
19p +/- 6 Tidal 26.5p
+/- 7.5p Wave
No sound on video
39
Options for Electricity Generation in 2020 - Renewable
Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Potential contribution to electricity supply in 2020 and drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p)
On Shore Wind
~20% available now ~ 2+p ~8.2p +/- 0.8p
Off Shore Wind
20 - 40%available but costly
~2.5 - 3p 12.5p +/- 2.5
Small Hydro 5% limited potential 2.5 - 3p11p for <2MW projects
Photovoltaic <<5% available, but very
costly15+ p 25p +/-8
Biomass ??5% available, but research
needed 2.5 - 4p 7 - 13p
Wave/Tidal Stream
currently < 10 MW may be
1000 - 2000 MW (~0.1%)
technology limited - major development not
before 20204 - 8p
19p +/- 6 Tidal 26.5p
+/- 7.5p Wave
Open Hydro commissioned off Eday – Sept 2007
Alstom Device seen at Hatston April 2013
Video of device
There is no sound to this video, but it demonstrates some of technicalities of the device
Video of device
There is no sound to this video, but it demonstrates some of technicalities of the device
ScotRenewablesFloating device
40
Options for Electricity Generation in 2020 - Renewable
Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Potential contribution to electricity supply in 2020 and drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p)
On Shore Wind
~20% available now ~ 2+p ~8.2p +/- 0.8p
Off Shore Wind
20 - 40%available but costly
~2.5 - 3p 12.5p +/- 2.5
Small Hydro 5% limited potential 2.5 - 3p11p for <2MW projects
Photovoltaic <<5% available, but very
costly15+ p 25p +/-8
Biomass ??5% available, but research
needed 2.5 - 4p 7 - 13p
Wave/Tidal Stream
currently < 10 MW may be
1000 - 2000 MW (~0.1%)
technology limited - major development not
before 20204 - 8p
19p +/- 6 Tidal 26.5p
+/- 7.5p Wave
Severn Barrage/ Mersey Barrages have been considered frequently
e.g. pre war – 1970s, 2009
Severn Barrage could provide 5-8% of UK electricity needs
In Orkney – Churchill Barriers
Output ~80 000 GWh per annum - Sufficient for 13500 houses in Orkney but there are only 4000 in Orkney. Controversy in bringing cables south.
Would save 40000 tonnes of CO2
Tidal Barrages 5 - 15%
technology available but unlikely for 2020. Construction time ~10 years.
In 2010 Government abandoned plans for development
26p +/-5
41
Options for Electricity Generation in 2020 - Renewable
Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Potential contribution to electricity supply in 2020 and drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p)
On Shore Wind
~20% available now ~ 2+p ~8.2p +/- 0.8p
Off Shore Wind
20 - 40%available but costly
~2.5 - 3p 12.5p +/- 2.5
Small Hydro 5% limited potential 2.5 - 3p11p for <2MW
Photovoltaic <<5% available, but very
costly15+ p 25p +/-8
Biomass ??5% available, but research
needed 2.5 - 4p 7 - 13p
Wave/Tidal Stream
currently < 10 MW ??1000 - 2000 MW
(~0.1%)
technology limited - major development not
before 20204 - 8p
19p Tidal 26.5p Wave
Tidal Barrages 5 - 15%In 2010 Government abandoned
plans for development26p +/-5
Geothermal unlikely for electricity generation before 2050 if then -not to be
confused with ground sourced heat pumps which consume electricity
42
Options for Electricity Generation in 2020 - Renewable
Future prices from Climate Change Report (May 2011) or RO/FITs where not otherwise specified
Potential contribution to electricity supply in 2020 and drivers/barriers
2002 (Gas ~ 2p)
May 2011 (Gas ~ 8.0p)
On Shore Wind
~20% available now ~ 2+p ~8.2p +/- 0.8p
Off Shore Wind
20 - 40%available but costly
~2.5 - 3p 12.5p +/- 2.5
Small Hydro 5% limited potential 2.5 - 3p11p for <2MW
Photovoltaic <<5% available, but very
costly15+ p
13-15p (2012 projection
Biomass ??5% available, but research
needed 2.5 - 4p 7 - 13p
Wave/Tidal Stream
currently < 10 MW ??1000 - 2000 MW
(~0.1%)
technology limited - major development not
before 20204 - 8p
19p Tidal 26.5p Wave
Tidal Barrages 5 - 15%In 2010 Government abandoned
plans for development26p +/-5
Geothermal unlikely for electricity generation before 2050 if then -not to be
confused with ground sourced heat pumps which consume electricity
43
Do we want to exploit available renewables i.e onshore/offshore wind and biomass?. Photovoltaics are mature but much more expensive than on shore wind.
Tidal and wave are not options for next 10 - 15 years except as demonstration projects. [technically immature ]
If our answer is NO
Do we want to see a renewal of nuclear power ?
Are we happy with this and the other attendant risks?
If our answer is NO
Do we want to return to using coal? • then carbon dioxide emissions will rise significantly
• unless we can develop carbon sequestration within 10 years UNLIKELY – confirmed by Climate Change Committee
[9th May 2011]If our answer to coal is NO
Do we want to leave things are they are and see continued exploitation of gas for both heating and electricity generation? >>>>>>
Our Choices: They are difficult
44
Our Choices: They are difficult
If our answer is YES
By 2020 • the UK will be dependent on GAS
for around 70% of our heating and electricity
The majority of which will be imported at volatile prices
Are we happy with this prospect? >>>>>>If not:
We need even more substantial cuts in energy use.
Or are we prepared to sacrifice our future to effects of Global Warming? - the North Norfolk Coal Field?
Do we wish to reconsider our stance on renewables?
Inaction or delays in decision making will lead us down the GAS option route and all the attendant Security issues that raises.
We must take a coherent integrated approach in our decision making – not merely be against one technology or another
45
Our looming over-dependence on gas for electricity generation
Data for modelling derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030.
Existing Coal
Existing Nuclear
Oil
Data for modelling derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030.
0
100
200
300
400
500
600
1970 1980 1990 2000 2010 2020 2030
TW
H (b
illio
ns o
f uni
ts (k
Wh)
)
Existing Coal
UK GasImported Gas
New Nuclear?
New Coal
Existing Nuclear
Other Renewables
Offshore Wind
Onshore Wind
Oil
• 1 new nuclear station completed each year after 2020.• 1 new coal station with CCS each year after 2020• 1 million homes fitted with PV each year from 2020 - 40% of homes fitted by 2030 • 15+ GW of onshore wind by 2030 cf 4 GW now
Data for modelling derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030.
• No electric cars or heat pumps
Version suitable for Office 2003, 2007 & 2010
• Brief Review of Climate Change Issues
• Overview of Energy Demand and consequential CO2
issues
• Energy Security Issues – particularly for the UK
including Renewable Energy Options for a Sustainable Future
• Technical options to reduce demand
• Reducing Demand and Carbon Emissions and saving money through Awareness and good Management
• Conclusions
46
Overview of oil, gas and alternative energy industry in the UK and Low Carbon options for the future
47
Generation of Electricity – Combined Heat & Power
Overall Efficiency - 73%
• Heat is rejected at ~ 90oC for supply to heat buildings.• City Wide schemes are common in Eastern Europe
EngineGenerator
36% Electricity
50% Heat
Gas
Heat Exchanger
Exhaust Heat
Exchanger
11% Flue Losses3% Radiation Losses
86%
Localised generation makes use of waste heat.
Reduces conversion losses significantly
Conversion efficiency improvements –
Building Scale Combined Heat/Cooling and Power
61% Flue Losses
36%
48
UEA’s Combined Heat and Power
3 units each generating up to 1.0 MW electricity and 1.4 MW heat
49
50
1997/98 electricity gas oil Total
MWh 19895 35148 33
Emission factor kg/kWh 0.46 0.186 0.277
Carbon dioxide Tonnes 9152 6538 9 15699
Electricity Heat
1999/2000
Total site
CHP generation
export import boilers CHP oil total
MWh 20437 15630 977 5783 14510 28263 923Emission
factorkg/kWh -0.46 0.46 0.186 0.186 0.277
CO2 Tonnes -449 2660 2699 5257 256 10422
Before installation
After installation
This represents a 33% saving in carbon dioxide50
Carbon Savings at UEA CHP Plant
5151
Load Factor of CHP Plant at UEA
Demand for Heat is low in summer: plant cannot be used effectivelyMore electricity could be generated in summer
51
Conversion efficiency improvements –
Building Scale Combined Heat/Cooling and Power
52
Schematic Representation
of a Power Station/ Heat Engine
Heat In Q1
Heat Out Q2
Work Out
W
Heat Engine
The Heat Pump / Refrigerator / Air Conditioner.
Schematic Representation
of a Heat Pump
Heat Pump
Heat Out Q1
Work IN
W
Heat In Q2
A Heat Pump is a reversed Heat Engine.
It is identical with a refrigerator/ air-conditioner
We define performance by Coefficient of Performance (COPP
If T1 = 323K (50oC) and T2 = 273K (0oC)
Practical efficiencies of 3 – 4 can be achieved
53 53
Throttle Valve
Condenser
Heat supplied to house
Evaporator
Heat extracted from outside
Low TemperatureLow Pressure
High TemperatureHigh Pressure
Responding to the Challenge: Technical SolutionsThe Heat Pump
Any low grade source of heat may be used• Typically coils buried in garden• Bore holes
Compressor
A heat pump delivers 3, 4, or even 5 times as much heat as electricity put in. We are working with thermodynamics not against it.
A typical Air conditioning/Refrigeration Unit
Uses electricity to drive compressor
节流阀Throttle Valve
冷凝器
绝热
Condenser
Heat rejected
蒸发器
为冷却进行热提取
Evaporator
Heat extracted for cooling
高温高压
High TemperatureHigh Pressure
低温低压
Low TemperatureLow Pressure
Compressor
压缩器
54
A more efficient way to provide Air-Conditioning
Electricity
Absorption Heat Pump
Adsorption Heat pump reduces electricity demand and increases electricity generated
节流阀Throttle Valve
冷凝器
绝热
Condenser
Heat rejected
蒸发器
为冷却进行热提取
Evaporator
Heat extracted for cooling
高温高压
High TemperatureHigh Pressure
低温低压
Low TemperatureLow Pressure
外部热
Heat from external source
W ~ 0
吸收器
吸收器
热交换器
Absorber
Desorber
Heat Exchanger
55
A 1 MW Adsorption chiller
1 MW 吸附冷却器
• Reduces electricity demand in summer
• Increases electricity generated locally
• Saves ~500 tonnes Carbon Dioxide annually
• Uses Waste Heat from CHP
• provides most of chilling requirements in summer
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UEA’s Aborption Chiller
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Sustainable Options for the future?Energy GenerationSolar thermal - providing hot water - most suitable for domestic installations, hotels and schools – generally less suitable for other businesses
•Solar PV – providing electricity - suitable for all sizes of installation
• Example 2 panel ( 2.6 sqm ) in Norwich – generates 826kWh/year (average over 7 years).
• The more hot water you use the more solar heat you get!
• Renewable Heat Incentive available from late 2013/ early 2014
• Area required for 1 kW peak varies from ~ 5.5 to 8.5 sqm depending on technology and manufacturer
• Approximate annual estimate of generation
= installed capacity * 8760 * 0.095
hours in year load/capacity factor of 9.5%
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Options available for the HouseholderEnergy Generation•Micro Wind - roof mounted turbines
•Mini Wind - mast mounted turbines – can be good as long as well clear of buildings, trees, etc – can be a good option for farms
Building Mounted - ~ 1kW machines ~ generally poor performance because of turbulence except in a few locationsNot generally recommended
Mast mounted away from buildings - 6kW Potential output 6000 – 10000 kWh depending on location
Vertical Axis machine – better in turbulence
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Alternative Strategies for Financing• Consumer purchases system and benefits from both reduction in
imported electricity and Feed In Tariff – suitable for both domestic and commercial properties for those who are capital rich but income poor.
• Company pays for and installs system and claims the Feed In Tariff – the owner of land benefits from reduced energy bills – for those with limited capital and less concerned with income.
• Schemes exist for • small wind – e.g. Windcrop who offer 5kW turbines which are less
affected by planning issues • Domestic/community PV up to 50kW
Images courtesy of WindCropHonningham Thorpe, Norfolk
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Options available for the Householder/CommunityEnergy Generation
•Onshore Wind - sensible for community schemes – e.g. Orkney, Germany, Denmark etc – the cheapest form of renewable energy
• Biomass boilers - can be sensible but need a reliable fuel supply. In cost terms with the proposed Renewable Heat Incentive there are attractions for homes heated by oil or electricity but not, at present for those with mains gas.
• Most convenient if running on pellets
• Cheaper with wood chip but more difficult to automate
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Ground Source: Heat Pumps
~ twice floor area of building is required for heat collection.Best performance with under floor heating.
Options available for heating buildings– Heat Pumps
Air source heat pumps require external fan system, and are not as efficient as air temperature is low when most heat is needed.
Retro fitting air-source heat pumps with existing radiators will lead to poor COP, but could be improved by fitting double radiators and/or a buffer tank
• Brief Review of Climate Change Issues
• Overview of Energy Demand and consequential CO2
issues
• Energy Security Issues – particularly for the UK
including Renewable Energy Options for a Sustainable Future
• Technical options to reduce demand
• Reducing Demand and Carbon Emissions and saving money through Awareness and good Management
• Conclusions
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Overview of oil, gas and alternative energy industry in the UK and Low Carbon options for the future
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How many people know what 9 (or 16) tonnes of CO2 looks like?
In UK ~5 hot air balloons per person per year.
In Saudi Arabia ~ 9 hot air balloons
On average each person in UK causes the emission of 9 tonnes of CO2 each year.
In Saudi Arabia it is 16 tonnes
"Nobody made a greater mistake
than he who did nothing because he thought he could do only a little."
Edmund Burke (1727 – 1797)
Raising Awareness
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Raising Awareness
• A Toyota Corolla (1400cc): 1 party balloon every 60m.
• 10 gms of carbon dioxide has an equivalent volume of 1 party balloon.
• Standby on electrical appliances up to 20 - 150+ kWh a year - 7500 balloons. (up to £15 a year)
• A Mobile Phone charger: > 10 kWh per year ~ 500 balloons each year.
• Filling up with petrol (~£55 for a full tank – 40 litres) --------- 90 kg of CO2 (5% of one hot air balloon)
How far does one have to drive in a small family car (e.g. 1400 cc Toyota Corolla) to emit as much carbon dioxide as heating an old persons room for 1 hour?
1.6 miles
At Gao’an No 1 Primary School in Xuhui District, Shanghai
上海徐汇区高第一小学
• A tumble dryer uses 4 times as much energy as a washing machine. Using it 5 times a week will cost ~ £100 a year just for this appliance alone and emit over half a tonne of CO2.
School children at the Al Fatah University, Tripoli, Libya
Electricity Consumption in an Office Building in East Anglia
0
5000
10000
15000
20000
25000
30000
35000
40000
45000
Jan Apr Jul Oct Jan Apr Jul Oct Jan Apr Jul Oct
2003 2004 2005
Co
ns
um
pti
on
(k
Wh
)
• Consumption rose to nearly double level of early 2005.
• Malfunction of Air-conditioning plant.
• Extra fuel cost £12 000 per annum ~£1000 to repair fault
• Additional CO2 emitted ~ 100 tonnes.
Low Energy Lighting Installed
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Conclusions• Global Warming will affect us all - in next few decades
• Energy Security will become increasingly important, particularly in the UK.
• Energy costs are rising mostly from increasing scarcity of traditional fossil fuels
• Inaction over making difficult decisions now will make Energy Insecurity and cost increases more likely in future.
• Move towards energy conservation and LOCAL generation of renewable energy and small changes in behaviour
A secure, sustainable and cost effective future will require:
• Effective Awareness and Management to reduce demand
• Technical Solutions to reduce demand
• Innovation use of low carbon energy sources
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直译):“如果你不改变,你将止步于原地。”Lao Tzu (604-531 BC)
Chinese Artist and Taoist philosopher
FINALLY
"If you do not change direction, you may end up where you are heading."
http://www.uea.ac.uk/~e680/cred/cred.htm
This presentation will be available from tomorrow at
Conclusions and Reflections