It is surprising that some people still believe electricity to be 100% efficient (and clean).

An electric heater may well be highly efficient in itself, but the generation of electricity, most of which still comes from fossil fuel power stations of low efficiency and high carbon emissions, and the further losses in transmission lines, make electricity an inefficient and polluting energy source. Hence the negative loadings in the Code for Sustainable Homes. Of course, this would be improved if we could use district generating stations using low-carbon fuels.

Richard Vogt