Sunday, 9 January 2011

Rambling thoughts on wind and power generation, part 1

There is a lot of talk on the outdoor blogs about the number and size of windfarms being created in the Scottish mountains; Alan Sloman has written a number of excellent articles about a new wind farm in the Monadhliath range of hills.

Not being able to better his prose, and also not having a particular knowledge of that area of Scotland, I thought that I would look at the problem from other angles. Mainly: is it actually worth building wind farms?

What problems are we trying to solve in building wind farms? Put simply, our nation is faced with two significant energy-related problems:
  • Global warming
  • Energy security
Unfortunately, wind power does little to solve either of these. Wind power is intermittent in nature, whilst energy use is cyclical according to time of day and season. For much of the time we will have nowhere near enough power to meet demand. Part 2 will look into this a little further.

The answer, according to environmentalists, is to store the power for when it is needed. This is done in various places, such as the Ffestiniog and Dinorwig pump-storage schemes in Wales. These pump water up to reservoirs using electricity during the night, when there is a surplus of cheap power, and release it at times of peak demand. I have heard claims that we just need to build more of these. There are several obvious problems with this:
  • There are few sites suitable for such schemes; you need a large height difference between the storage reservoirs and the generating plant, and the upper lake needs to be large to store the water. 
  • Building such schemes are hardly green; a million tonnes of concrete were used at Dinorwig. Building large lakes in our upland areas also has obvious environmental consequences.
  • They depend on cheap electricity to pump the water up; wind power is hardly cheap and is currently massively subsidised.
Of course, there are proposals for other means of storing energy, for instance molten salt storage. However these have only been built on a small scale, and there are a number of concerns about them, including pollution. We cannot bet the future on untried technologies.

We need maximum power in winter and yet, as happened recently, the cold weather coincided with low wind speeds. Therefore the wind farms were at low efficiency when we needed them most. This means that we will either need a massive over-capacity of wind power, some form of (currently untested at scale) power storage mechanism, or more traditional power plants to provide back-up power.

There is also the issue of how inefficient wind power is.According to the Telegraph, an area of land the size of Wales will need to be covered with turbines to generate just one-sixth of the country's energy needs. From this, it is clear that wind power is not the answer to either of the two problems that face us.

We need more honesty in the debate. What I would like to see are publicly-available and honest (*) figures about the power generated by wind farms compared to their stated capacity. Fortunately we have such figures (see part 2).

Wind farms have other problems. People campaigning against wind farms are often called NIMBYs, sometimes rightly. However such name-calling does not hide the fact that, in many cases, they have a point. Our uplands are precious, and anything that permanently alters them should only be done with care. It would be exceptionally hard for me to get planning permission to build a cottage in Brassington in Derbyshire, yet the Government are allowing four massive 102-metre tall turbines to be built nearby. A house can have negligible visible impact on a landscape; these turbines will be visible for miles around.

I was once told by a Greenpeace representative that, if necessary, windfarms could be dismantled and the wilderness reinstated. He was assuming that the turbines just sat on large blocks of concrete that could be easily removed. That may be the case; but it does not account for the miles of haul roads and power lines that are needed for construction and maintenance of the turbines, or to distribute the power. It may not be fashionable to say so, but this is a significant form of pollution of some of our most precious places.

I am not against all wind farms; off-shore ones may be useful (and expensive). But given the manifest disadvantages of wind, we really have to weigh the advantages of wind against the disadvantages on a case-by-case basis. The Scottish Government in particular is failing in this regard.

It seems to me that many proponents of wind power are looking at the advantages and ignoring the disadvantages. They think 'green' as being solely about power, and not about wildernesses.

 Will future generations thank us for destroying some of the last wildernesses in Britain in a perhaps-pointless quest for 'green' energy? I think not.

(*) I say honest, because figures have been massaged in the past. Solar installations in Spain have been accused of fraud. In one case, investigators noticed that a solar power plant was impossibly generating significant power at night. It turns out that as solar power generators can charge more for their power, they were using diesel generators to produce electricity and selling it at higher cost, pocketing the profit and defrauding the public.

1 comment:

Alan Sloman said...

A well thought out piece, David. Looking forward to Part 2.