SIR – Graham Hoyle asks for some truths about power (Letters, January 7) so here are some for him to mull over.

Allowing for the CO2 produced in construction, wind turbines produce just 5g of CO2 per kWh; the figure for coal and gas-generated electricity is over 400g for the same amount of power.

The key to the development of electric cars is the recharging of the batteries by electricity that isn’t produced by burning coal, gas or oil. This means solar, wind, tidal and nuclear power.

Over the years, the coal and gas-fired power stations and the distributing National Grid have received considerable subsidy from central governments of all outlooks.

Such support for energy supply systems that don’t produce CO2 should be considered an investment in our future, as without it we won’t cope with a climate changed by unlimited CO2 and the peaking of crude oil.

Keith Thomson, Heights Lane, Bradford