Recipient of James Watt Gold Medal for Energy Conservation Keith Tovey ( ) M.A., PhD, CEng, MICE,...
-
Upload
faith-mclaughlin -
Category
Documents
-
view
214 -
download
0
Transcript of Recipient of James Watt Gold Medal for Energy Conservation Keith Tovey ( ) M.A., PhD, CEng, MICE,...
Recipient of James Watt Gold Medal for Energy Conservation
Keith Tovey ( 杜伟贤 ) M.A., PhD, CEng, MICE, CEnvReader Emeritus: University of East Anglia 1
Low Carbon Dinner – March 1st 2011West Suffolk College
Pathways to an Energy Secure and Low Carbon Future
Pathways to an Energy Secure and Low Carbon Future
Background
Awareness Raising
Effective Management
Innovative Technical Solutions
Low Carbon Energy Production• Nuclear electricity• Renewable Energy Generation – Heat, Electricity and Transport• Carbon Capture and Sequestration
2
• Good Record Keeping and Objective Analysis of data > leading to energy reduction through good management
• Building design• Use of Efficient appliances/Technologies
0
50
100
150
200
250
300
350
400
450
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
bil
lio
ns
of
kWh
nuclear new nuclear coal
new coal oil renewablesgas medium renewables high renewables
Our looming over-dependence on gas for electricity generation
We need an integrated energy supply which is diverse and secure.
We need to take Energy out of Party Politics.!
0
20
40
60
80
100
120
140
2000 2004 2008 2012 2016 2020
Bil
lion
cu
bic
met
res
Actual UK production
Actual UK demandProjected productionProjected demand
Import Gap
Energy Security is a potentially critical issue for the UK
On 7th/8th December 2011: UK Production was only 39%: 12%
from storage and 49% from imports
UK becomes net importer of gas
Completion of Langeled Gas Line to Norway
Oil reaches $140 a barrel
Prices have become much more volatile since UK is no longer self sufficient in gas.
Gas Production and Demand in UK
Wholesale Electricity Price surge in January and December 2010 when Gas imports are high.
kWh % cost Rank % Renewables 2008Norwich 3,535 79% 6 0.0%Ipswich 4,349 97% 159 0.0%Waveney 4,417 99% 181 1.9%Broadland 4,618 103% 231 3.0%Great Yarmouth 4,699 105% 252 30.0%St Edmundsbury 4,869 109% 280 1.0%Breckland 5,028 112% 312 31.8%Forest Heath 5,174 116% 336 0.0%Babergh 5,252 117% 343 0.1%South Norfolk 5,347 119% 358 5.0%Suffolk Coastal 5,371 120% 360 1.0%North Norfolk 5,641 126% 385 1.3%Mid Suffolk 5,723 128% 390 18.3%King's Lynn and West Norfolk 5,731 128% 393 2.5%
UK Average 4478• % of average cost of electricity bills compared to National Average • Rank position in UK out of 408 Local Authorities
Average house in Norwich emits 1.87 tonnes of CO2 from electricity consumptionin Kings Lynn 3.04 tonnes of CO2 (based on UK emission factors)
Average household electricity bill in Norwich is 64% that in Kings Lynn
Average Domestic Electricity Consumption in Norfolk and Suffolk
Installations under the Feed In Tariff Scheme (18/02/2011)
6
Technology
Domestic Installations
Other Installations* Total
NumberInstalled Capacity
(MW)Number
Installed Capacity
(MW)Number
Installed Capacity
(MW)SuffolkHydro 0 0 1 0.49 1 0Micro CHP 0 0 0 0 0 0Photovoltaic 466 1.134 5 0.023 471 1.157Wind 19 0.125 0 0 19 0.125
Total 485 1.26 6 0.513 491 1.773NorfolkHydro 2 0.021 0 0 2 0.021Micro CHP 1 0.001 0 0 1 0.001Photovoltaic 476 1.118 10 0.081 486 1.199Wind 20 0.142 5 0.034 25 0.176Total 499 1.281 15 0.115 514 1.396
• * Commercial, Industrial and Community Schemes.• Note: Chris Huhne announced a potential curtailment of large FIT
schemes (>50kW) in early February 2011.
7
Mostly Eye and Thetford
Scroby
Renewable Energy Generation in Suffolk and Norfolk 2009 - 10
Generation in GWh
stations GWhCapacity
(kW)Load
Factor
Biomass 3 326 61816 60.2%Landfill Gas
18 127 26719 54.3%
Off-shore Wind
1 170 60000 32.3%
On-shore Wind
5 58 24500 27.0%
Sewage Gas
2 10 4836 23.6%
Total 29 691 177871
Total Demand in Norfolk and Suffolk 7803.2 GWh% Renewables 8.9%
National Average 7.8%
Target 10.4%
Electricity Supply in Norfolk and Suffolk (GWh)
8
2009 Data for Renewables and SizewellOther Data based on typical load factors
Existing Renewables
Sizewell B
Great Yarmouth
• Total generation in Norfolk and Suffolk (allowing for losses)
~ 11000 GWh
• Total demand in Norfolk and Suffolk = 7803 GWh
• Net export to remainder of UK ~ 3200 GWh
• Embedded Renewable Electricity such as ON-SHORE wind will be used near demand incurring limited transmission losses.
• Large Scale Generation incurs 8.5% trnamission/distribution loss Export of Electricity to rest of UK
Approximate Carbon Emission factors during electricity generation including fuel extraction, fabrication and transport.
9
Impact of Electricity Generation on Carbon Emissions.
Fuel Approximate emission factor
Comments
Coal 900 – 1000g Depending on grade and efficiency of power station
Gas 400 – 430g Assuming CCGT – lower value for Yarmouth
Nuclear 5 – 10g Depending on reactor type
Renewables ~ 0 For wind, PV, hydro
Overall UK ~530g Varies on hour by hour basis depending on generation mix
Suffolk & Norfolk (2009)
~83g Sizewell B, Yarmouth and existing renewables
• In 2009 Norfolk and Suffolk was a very low carbon zone in UK• But current accounting procedures do not allow regions to promote this.• A firm in Norfolk / Suffolk would have only 16% of carbon emissions
from electricity consumption
10
0%10%20%30%40%50%60%70%80%90%
100%
0 12 24 36 48 60 72
hours
Ind
ex
rela
tiv
e t
o m
ax
imu
m
single wind farmall "visible" windfarmsdemand
Variation in UK Electricity and Demand and Wind Generation.
-60%-50%-40%-30%-20%-10%
0%10%20%30%40%
0 12 24 36 48 60 72Hours
Var
iati
on f
rom
Dem
and
windnuclear
• A single wind farm may have moderate variation in output
• Output smoothed if whole UK is considered.
• Demand also has significant diurnal variation
Data for 23-25th February 2011 from www.bmreports.com
• Output from nuclear plant is nearly constant
• difference in variation in nuclear output compared to demand is comparable with difference in demand and wind generation
11
Impact of Electricity Generation on Carbon Emissions.
Electricity exported from Norfolk/Suffolk in 2009 to rest of UK ~ 3200 GWh representing a net CO2 saving of ~ 1.43 Mtonnes
At £12.50 per tonne (current EU-ETS price), this represents a benefit of £18 million to rest of UK in carbon saved.
• However – in 2010, Sizewell B was off line from over 6 months, so is this low carbon electricity sustainable?
• Is such a reliance on a single source a secure or sustainable?
• From BBC Website – 27th May 2008
“Hundreds of thousands of homes suffered power cuts after a fault caused an unplanned shutdown at the Sizewell B nuclear power plant in Suffolk. Homes and businesses in London, and East Anglia were affected…..”
• Local generation avoids most transmission and distribution losses and small scale schemes avoid such major power blackouts.
• However – over decentralisation may lead to distribution grid problems if there is no reinforcement.
12
The Behavioural Dimension: Awareness raisingElectricity Consumption
0
1000
2000
3000
4000
0 1 2 3 4 5 6
No of people in household
kW
h i
n p
erio
d
1 person
2 people
3 people
4 people
5 people
6 people
Variation in Electricity Cosumption
-100%
-50%
0%
50%
100%
150%
200%
1
% D
iffe
ren
ce f
rom
Ave
rage
1 person 2 people 3 people4 people 5 people 6 people
Social Attitudes towards energy consumption have a profound effect on actual consumption
Data collected from 114 houses in Norwich between mid November 2006 and mid March 2007
For a given size of household electricity consumption for appliances [NOT HEATING or HOT WATER] can vary by as much as 9 times.
When income levels are accounted for, variation is still 6 times
12
1313
0
200
400
600
800
1000
-4 -2 0 2 4 6 8 10 12 14 16 18
Mean |External Temperature (oC)
En
ergy
Con
sum
pti
on (
kW
h/d
ay)
Original Heating Strategy New Heating Strategy
Good Management has reduced Energy Requirements
800
350
Space Heating Consumption reduced by 57%
CO2 emissions reduced by 17.5 tonnes per annum. 13
Performance of ZICER Building
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
14
Low Carbon Strategies: making efficient use of technology
15
0.0
1.0
2.0
3.0
4.0
5.0
F M A M J J A S O N D J F M A M J JMonth
kWh/
day
BSD1 BS01
BS02 BS16
BS17 BS26
BS27 BS52
Solar Thermal solutions can provide hot water
• However, performance can be significantly affected by way normal central heating boiler is used for backup.
• A factor of two in output has been measured for otherwise identical installations
Low Carbon Strategies: making efficient use of technology
3 units each generating 1.0 MW electricity and 1.4 MW heat
16
e.g. UEA’s Combined Heat and Power
Improved insulation, improved appliance efficiency, (power packs, lighting etc, etc). Energy conserving technologies e.g. heat pumps, CHP etc.
17
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/ 2000Total 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 dioxide17
Significant Savings in CO2 emissions are possible with CHP
A 1 MW Adsorption chiller
• Uses Waste Heat from CHP
•Provides chilling requirements in summer
•Reduces electricity demand in summer
•Increases electricity generated locally
•Saves ~500 tonnes Carbon Dioxide annually.
18
Load Factor of CHP Plant at UEA• Demand for Heat is low in
summer: plant cannot be used effectively.
• More electricity could be generated in summer
• A Paradox: Largest amount of electricity was imported when demand was least!
For optimum results: Care in matching demand is needed
• Peak output is 34 kW
• All electricity must be converted from DC to AC by use of inverters.
• Inverters are only 91% efficient
19
Building Integrated Renewable Electricity Generation
Typical Solar Array: ZICER Building, UEA
• Most use of electricity is for computers
• DC power packs are typically ~70% efficient
• Only 2/3rds of costly electricity is used effectively.
• An integrated system in a new building would have both a DC and AC network.
• Reduced heat gain in building leading to less air-conditioning requirements.
202020
Arrangement of Cells on Facade
Individual cells are connected horizontally
As shadow covers one column all cells are inactive
If individual cells are connected vertically, only those cells actually in shadow are affected.
Cells active
Cells inactive even though not covered by shadow
20
For optimum results: Care is needed in design
21
A Pathway to a Low Carbon Future: A summary
4. Using Renewable Energy
UEA Advanced Gasifier CHP
5. Offset Carbon Emissions
3. Using Efficient Equipment
1. Raising Awareness
0
200
400
600
800
1000
-4 -2 0 2 4 6 8 10 12 14 16 18
Mean |External Temperature (oC)
En
ergy
Con
sum
pti
on (
kW
h/d
ay)
Original Heating Strategy New Heating Strategy
O
2. Good Management
21
22
Seeking Effective Low Carbon Solutions
Some costs for providing a low carbon future
• Small scale solar PV under the Feed in Tariff
~ £700+ per tonne CO2 saved
• On-shore wind under Renewable obligation
~ £90+ per tonne CO2 saved
• Cavity Insulation
~£20 - £30 per tonne CO2 saved
• Effective Energy Management can often be cost negative in terms of CO2 saved.
• An effective strategy will focus on most cost effective solutions.
23
Conclusions• Energy Security and a Low Carbon Strategies are important for a
sustainable and prosperous future.
• Strategies should not focus just on energy generation but also on energy reduction
• Better management can lead to significant and often cheaper solutions for a low carbon future
• Integrate effectively the use of newer technologies with actual demand e.g. local generation avoiding unnecessary losses – also avoid unnecessary
conversion form DC to AC etc.
• East Anglia provides and exports low carbon electricity with emissions less than 20% of national average.
• East Anglia has Academic Institutions which are taking a lead in developing the low carbon future
e.g. World’s First MBA in Strategic Carbon Management run by the Norwich Business School at UEA.
Lao Tzu (604-531 BC) Chinese Artist and Taoist Philosopher
"If you do not change direction, you may end up where you are heading."
And Finally!