REMEMBERING that the principal purpose of renewable energy is to reduce carbon dioxide emissions, should wind turbines be taken down and moved if they're put up in the wrong place – ignoring the fact for the moment that they shouldn't have been incorrectly sited in the first place?

Have those who have made this suggestion realised that enormous amounts of concrete are used to provide foundations?

Depending on ground conditions, a 50kW turbine, such as that recently permitted at Bow, will need over 100 tonnes of concrete to form its base and the proposed 500kW turbine at Langland, Morchard Bishop, about 650 tonnes.

And what happens to all this concrete when the turbine is decommissioned?

It gets left in the ground.

Yes, in theory, a wind turbine can be moved but I can't see the point.

In the case of the 50kW turbine it would take the best part of three years for the electricity generated by the turbine to displace the CO2 emissions created in the manufacture of the concrete foundation – and that doesn't include the emissions created in digging the hole, moving the concrete to site, the manufacture of the turbine and its transport costs to site.

On another issue, wind turbines and solar panels only ever duplicate other means of electricity generation, usually gas turbines.

These need to be kept on stand-by to be brought into use when the wind drops or the sun sets.

So what are we doing? Duplicating capital costs by erecting wind turbines or taking land out of food production to produce intermittent electricity supply that's so expensive that our electricity bills keep being put up to pay for the feed-in tariff subsidies.

We are all paying for it.

Roland Smith

Nymet Rowland