APPENDIX ONE
CARBON REDUCTION CONTRIBUTIONS FROM MICROGENERATION
The following tables summarises the results
of the Micropower Council's analysis of the potential carbon (and
energy) savings that can be delivered using microgeneration to
displace the equivalent electrical output of 1GW baseload CCGT
or, for heat measures, the amount of gas that would be consumed
by a CCGT in a year. It should be noted that the number of installations
quoted is well below the mid to long term market potential for
most of these technologies and no allowance has been made for
technological developments that could lead to major performance
enhancements in the future (in particular the potential for fuel
cells CHP technologies).
Table 1 COMPARISON
OF MICROGENERATION WITH CENTRAL SUPPLY AND ENERGY EFFICIENCY MEASURES
| Technology | Electricity produced centrally TWh pa
| Electricity delivered to customer TWh pa |
Gas burn TWh pa | Number of units
| MtCO2 pa | [22]MtC pa
| Comments |
| | |
| | | |
|
| CCGT | 8 | 7 |
16 | 1 | 3[23]
| ~1 | 1 GW CCGT operating at 90% load factor. We have assumed 50% conversion efficiency and 10% T&D losses.
|
| Wind (grid connected) | 8 |
7 | 0 | ~1,000 |
0 | 0 | Large on-shore ~3GW
|
Domestic
PV | n/a | 7
| n/a | 7,000,000 | 0
| 0 | We assume installation of 1-1.5 kW producing ~1MWh pa—this is a conservative assumption domestic systems can be larger.
|
| Domestic wind | n/a | 7
| n/a | 7,000,000 | 0
| 0 | Current, near market, roof top sized turbines produce up to 4MWh pa. We have used a conservative assumption of machines of approx 1kW (~1MWh pa).
|
| m-CHP | n/a | 7
| 7 | 3,000,000 | 1[24]
| ~0.5 | The gas burn is the additional gas burnt above that required to meet the heat load using a condensing boiler.[25]
|
| A+ Fridge | n/a | 7
| n/a | 28,000,000 | 0
| 0 | Replacing an old fridge with an A+ rated fridge
|
| light bulbs | n/a | 7
| n/a | 280,000,000 | 0
| 0 | Using low energy light bulbs
|
| | |
| | | |
|
Table 2 COMPARISON OF MICRO-HEAT TECHNOLOGIES DISPLACING
THE NEED FOR CENTRALLY DELIVERED GAS OR/ELECTRICITY (I.E. DISPLACING
EITHER 16TWh OF GAS (THE AMOUNT NeEDED FOR 1GW OF GAS FIRED CCGT
OPERATING BASELOAD) OR THE SAME AMOUNT OF ELECTRICITY AS WOULD
BE PRODUCED BY SUCH A CCGT
Technology | Electricity saved (point of use) TWh pa
| Gas saved at point of use TWh pa | Number of units
| MtCO2 SAVED pa | MtC SAVED pa
| Comments |
| | |
| | | |
| CCGT | 0 | 0 |
1 | 0 | 0 | 1 GW CCGT operating at 90% load factor. For simplicity, we have assumed 50% conversion efficiency and 10% T&D losses.
|
| Wind (grid connected) | 0 |
n/a | ~1,000 | 3 |
1 | Large on-shore wind-farm~3GW |
| Solar thermal | n/a | 16
| 7,000,000 | 3 | 1
| Based on an estimated output of 1-2MWh of useable heat. This displaces some 2.4MWh[26] of gas after correcting for efficiency of gas burn and losses in the hot water system.
|
| Biomass | n/a | 16
| 1,000,000 | 3 | 1
| Based on displacing gas used to service average typical heat and hot water load (19MWh pa).[27]
|
| G or A heat pump | 7 TWh pa |
0 | 1,000,000 | 3 |
1 | Based on delivering a heat load of [28]15MWh per annum using a COP 3 heat pump in premises previously heated by electricity (ground source should do better than this air source less well), saving 10 MWh of electricity per annum.
|
| | |
| | | |
22
All figures are rounded to the nearest whole number (or whole
millions) except for Carbon which is rounded to the nearest 0.5MtC. Back
23
Based on emissions factors used by CTI/DEFRA for benchmarking
generation for Phase II of the EU ETS. (http://www.dti.gov.uk/energy/sepn/proposed_benchmark_phase2.pdf)
51.45 tC02/TJ. Back
24
Based on SAP 2005 (table 12) figure of 0.194kg of CO2 per kWh
at premises. Back
25
Developers figures based on trails. It should be noted that the
comparator for the m-CHP is a condensing boiler whereas we have
used current national average for other technologies. Back
26
Information from the Solar Trade Association. Back
27
In line with recommendations from the Carbon Trust (Section 4),
we have not included any Carbon emissions from transportation
of fuel (http://www.thecarbntrust.co.uk/carbontrust/about/publications/Biomass%20Sector_FINAL.pdf). Back
28
Average gas consumption of heat and hot water is ~19MWh pa (source
EST), converted to a heat load using an average efficiency of
79% (the value used by Ofgem when estimating efficiency savings
under the EEC). Back
|
