PRI: Public Radio International

Scotland's wind turbines less eco-friendly than they appear

Sun, 06 May 2012 11:05:00 -0500

Scotland plans to harness its high wind concentration as a renewable energy source with wind turbines. Wind turbines have often been criticized as ugly and loud, but now they're being called potentially harmful to the environment. That's because wind turbines have been releasing carbon stored in peat bogs into Scotland's atmosphere.

Mike Barnard

Sun, 06 May 2012 18:44:34 -0500

Given that wind farms occupy about 0.01% of the land upon which they are erected when up, and about twice that when being constructed, it is hard to imagine that this will have a significant impact on peatland.
http://www.quora.com/How-much-land-does-1-gigawatt-of-wind-energy-require/answer/Mike-Barnard

For a comparison, here's an analysis of wind farm impacts on aquifers and ground water, a similarly sensitive subject. It includes comparisons with alternative forms of energy such as coal and other fossil fuels for a sense of perspective.
http://www.quora.com/Wind-Power/Do-wind-turbines-have-an-impact-on-aquifers/answer/Mike-Barnard

As for how long wind turbines take to pay for themselves, the best numbers are that wind turbines pay back carbon in about three months and net energy in about five months. This is using ISO full-lifecycle accounting methods with external reviews. Three to thirty years as payback periods is indicative of a fairly skewed analysis. One person's memory is not as useful as referenced citations that can be assessed, as with the material in the link.
http://www.quora.com/How-long-does-it-take-a-typical-wind-turbine-to-generate-more-power-than-what-was-used-to-create-it/answer/Mike-Barnard

Gordon

Sun, 06 May 2012 20:48:54 -0500

Some 70% of Scottish wind farms are built on peatlands.

The other problem, not mentioned in this article, is that many of Scotland's new wind farms are being built in wet bogs.

These often require huge amounts of concrete in the foundations to stabilise the structure. Concrete has a large CO2 burden, adding to parback times.

We are also seeing increasing numbers of schemes in forests where large areas are being clear-felled. Taking out carbon sequestrators (peat and trees) in order to build industrial structures that only have a small marginal benefit in reducing CO2 emissions due to intermittency and backup problems makes very little sense.

Highlander

Mon, 07 May 2012 09:00:39 -0500

What a load of rubbish. Not really worth a reply. Payback times are ridiculous as stated here. Assume this is from an employee of Renewables Uk or similar.

Lecourt

Mon, 07 May 2012 13:09:59 -0500

Mr. Barnard asks some practical questions as to impact, which make sense to me. I wonder if a similar exercise has been done on fossil fuels (which have no hope of becoming carbon neutral, and use huge amounts of concrete and steel, while emitting GHG's whenever they run).
I have travelled extensively in Scotland and seen plenty of wind turbines installed, up and running. Most are on the high ground, whereas, by its very nature, peat bogs tend to be in the low lands. Something doesn't compute here.

Michele

Sat, 01 Sep 2012 21:19:31 -0500

Very much dependent on the spifciec engineering of the wind turbine. You are losing energy to friction, so the mechanics of the device are very important. All of that is not a consideration for fossil fuels becase the earth has done most of the conversion already by using gravity (i.e., pressure), which is basically infinitely available. If you are thinking not in terms of energy cost, but financail cost, then you really need to think about the supply chain. A single high-effeicncy wind turbine might cost $5MM to build, but there is operational cost, land cost, distribution and storage costs. All of that is baked into the end user price of a gallon of processed fossil fuels. I don't know the spifciec numbers, but I do know that none of the wind farms would be profitable without the government subsidies that they are getting ATM.That chart of 1996 California date someone posted showing that wind is the lowest cost seems highly suspect to me at a minimum it is looking at regulatory compliance costs for things like nuclear and fossil feuls, not just the cost of generating and delivering the energy. That is the problem with data "sound bites", they are a little to easy to quote without thinking about them.