Gas Fired Power Stations: Carbon Emissions

Charles Hendry
To ask the Secretary of State for Energy and Climate Change what recent estimate he has made of the likely carbon dioxide emissions per unit electric output from a modern (a) combined cycle gas turbine, (b) open cycle gas turbine and (c) integrated gasification combined cycle power station.

Mr. Kidney
The rate at which power stations emit carbon dioxide are determined by individual plant efficiencies which vary considerably in actual operation. DECC uses a range of reference values which are kept under review. These are based on the estimated likely efficiency achieved in the actual generation market, including efficiency degradation following commissioning. Such estimates will differ from those available in the technical literature which do not always reflect actual performance.

The figures shown in the following table for technologies are representative values based on electricity supplied to the grid after allowing for own use and transmission and distribution losses. The values represent emissions of carbon dioxide in kilograms per kilowatt hour unit of electricity.

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|Technology                                                 |kg CO2/kWh|
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|Combined cycle gas turbine (CCGT)                          |0.43      |
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|Open Cycle Gas Turbine (OCGT)                              |0.60      |
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|Integrated gasification combined cycle power station (IGCC)|0.73      |
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