SIR – Travelling west along the M62 from a stay in Hull recently, I was struck not by the fact that the Ferrybridge cooling towers were no longer there, but by the number of wind turbines dotted across the landscape. There were around 40 of the beasts visible across the skyline, only one of whose rotors was turning.

Now I don’t profess to be an expert in wind technology, but don’t these things have to turn to generate power, or am I missing the point?

A Waterhouse, Barmby Road, Bradford