SIR – A battery in a high-powered electric car is rated at 70 kWh. With fast charging, it is only 50 per cent efficient (half the electricity used is dissipated as waste heat).
It will therefore need 140 kWh of electricity for a single charge. The Drax power station uses about 0.31 kilogram of coal per kWh generated.
The coal used for a single charge therefore equates to 43 kilograms. A petrol car will require about 20 kilograms of petrol for the same distance. It follows that the electric car generates more than twice the CO2 of a petrol car.
Terri Jackson, Bangor, Co Down
The Daily Telegraph, Wednesday August 2nd 2017