There's inefficient, and then there's really inefficient

The 106 mostly Tory MPs who think wind power is a bad idea have had their day in the Sunday Telegraph, and new Secretary of State Ed Davey has been robust in his defence of wind as part of a mixed renewable portfolio. It is, of course, local planning that these MPs are after, as well as subsidies, and rumours are that the government is to produce guidance that 'rebalances' national and local planning considerations when it comes to the siting of onshore wind.

Rebalancing, that is ...er.. the shredding of planning guidance by the government down to just 50-odd pages, thereby, among other things giving national policy planning guidance a sharp tilt away from local vetoes on planning. The localising of planning demand is set out in an annex to the MPs letter not apparently published in the Sunday Telegraph and is well dissected in a 'mole' piece in The Week.

But stick for a minute with the central letter. "In these financially straightened times" the MPs declare, "We think it is unwise to make consumers pay, through taxpayer subsidy for inefficient and intermittent energy production that typifies on-shore turbines".

There are two points to think about here. One is dealt with very well by Damian Carrington in his Guardian blog, who points out that the consequence of these MPs wanting to "spread the savings between other types of reliable renewable energy production" could well mean energy being far more expensive since these other "reliable renewable" generation devices produce electricity at far greater expense per kilowatt hour than does onshore wind.

The other point has not to my knowledge been dealt with at all. This is that, on analysis, the confident assertion by our 106 anti-winders that consumers are paying for all this "inefficient and intermittent" wind through the nose doesn't look quite so clear. Not, that is, if you look at electricity production in the round, or at least enough in the round to take into account how efficient other forms of electricity production actually are by comparison with wind.

To make this calculation, you have to take into account the thermal efficiency of other forms of power - that is the extent to which fuel that goes in is actually produced as electricity, and doesn't just go up the chimney in hot air. Then you have to look at how often the plant itself is not producing at all, because it is closed, or broken down, or is being maintained. The resultant figure is the 'effective energy delivery' of the technology.

Hard to find out? Not really. It's all there on Table 5.10 of the Digest of UK Energy Statistics' (DUKES) a fine publication that our anti-winders would be well advised to consult more often.

So, our starter. Wind, we can generally say, has about 25 per cent "effective energy delivery". It produces electricity to about 25 per cent of its theoretical installed capacity, but when it does the fuel is free and none is wasted.

Gas is next up. Very efficient, one would think. But is it? Load factor of 60.6 per cent, thermal efficiency of 47.6 per cent, so it slides in just ahead of wind with an effective energy delivery of 29 per cent (but not very low carbon).

Nuclear - that's low carbon, isn't it?. Runs all the time. Must be the winner. Well, no: load factor in 2010 of 59.4 per cent. Thermal efficiency just 38.3 per cent - down there in third position with an effective energy delivery of 22.75 per cent.

And coal - well, it's not only very high carbon, but very inefficient. Much more so than wind: a 40.9 per cent load factor and thermal efficiency of just 36 per cent: A poor last with effective energy delivery of only 14.7 per cent.

I doubt whether these "facts" will stop any of the anti-winders or their allies going on about how hopelessly inefficient and unreliable wind is. But it is a largely groundless prejudice, and ought to be recorded as such. I am indebted to Edward Hyams, former chairman of the Energy Saving Trust for pointing me at this: it should be more widely disseminated, I think.

This article first appeared on Alan's Energy Blog.

Dr Alan Whitehead is the Labour Member of Parliament for Southampton Test.

He is a member of the House of Commons Energy and Climate Change Select Committee, as well as the Environmental Audit Select Committee.