I am sorry to perhaps put a little dampener on Ian Johnstone’s enthusiasm for full electric and hybrid vehicles (Letters, 7 February) – a move which, incidentally, I do in principle support.
It is true that an electric car is about four times more efficient in converting its battery energy into propulsion than its fossil fuel equivalent with regard to the chemical energy in its on-board fuel tank .
However, if that electrical energy comes from fossil fuel then its delivery to the vehicle battery could have an efficiency of only about 35 per cent. So the all-electric car would only be a little better and the hybrid probably worse with regard to emissions.
And from where will that electrical energy come? We may note the closure of our fossil-fuel and nuclear power plants in a very few years’ time will require about a 3-5,000 wind turbine equivalent just to maintain our current generation requirement.
Norway and Sweden have long tripled our total electricity per head, mainly from low-emission sources (nuclear and hydro) but, as far as I am aware, have not largely converted to electrically powered transport, which, of course, would require a huge increase in generation capacity.
(Dr) A McCormick