From Perry Bebbington
Robert Laing says he would not drive any further if his new car used less fuel than the old one (8 May, p 30). But he would save money on petrol, and presumably he would spend that money on something he would not otherwise have bought. Pretty much everything I can think of that he might buy will have used energy in its manufacture, distribution or during its use. So, cheaper energy does lead to greater use, even if the connection between the two is not direct.
Nuthall, Nottinghamshire, UK
