§ Mr. Dobson
To ask the Secretary of State for Energy what are the factors by which his Department multiplies oil and gas tonnages to achieve coal equivalents; and when these were last changed or modified.
§ Mr. Wakeham
The factors generally used to convert data on tonnages of oil and gas (including petroleum gases) to coal equivalent are 1.7 and 2, respectively. These factors, which have been widely adopted for a number of years by both national and international organisations, are based on standard thermal contents of 250 therms per tonne of coal, 425 therms per tonne of oil and 500 therms per tonne of gas. I am not aware of any reason why these factors should be changed or modified.