How safe are wind turbines?

I am not on about the small wind turbines that you see from time to time on a boat. To be honest when I looked at them a few years ago as a possible source of "free" energy - after the initial costs and installation.  I was put off by the need to install and remove whenever mooring up for the day. They seemed to be more trouble than they are worth. Solar seemed to be the better option.

I don't think much about commercial wind turbines as a renewable energy source either  The wind does not always blow with sufficient strength and not always at the best time of day or the best time of year. I have not been to interested in them other than as an occasional spectator as we have a few visible in the distance. However, it seems that there are a number of pretty serious problems with their operation.

I was listening to a phone in program on the radio and as a change from the usual pro or anti wind turbine activist. It was an informal and refreshingly honest interview with an engineers who works on them. It seems that there are frequent problems that most people are unaware of. One problem is that they are lethal for moorland birds and even bats.

Because they are often located on high ground they are frequent occurrences of them being struck by lightning. Blades are known to fall off and to be thrown off at high speed. They sometimes burst into flames and the support towers, break or even fall over from time to time. 

However, it seems that ice is also known to build up on the blades. Which can then break off in lumps and be thrown for very long distances. They can and do sometimes run away with themselves and the blades break up. There are also problems with wind noise generated by the spinning blades. One thing that we all need to know are the safe recommended separation distances between a turbine and a public place.

This triggered my inquisitive nature to find out a bit more. The problem of constant turbine noise nuisance  underlines one of the needs for sensible separation distances. As doest the problem of ice and bits of the blades falling off. So people are right to question their construction close to houses or transport routes. In Scotland there is planning guidance which suggests a 2 kilometre separation distance. Nothing so sensible exists in England and Wales. In the 1990’s the DTI was suggesting a 450m separation distance for turbines that back then were a maximum of 60 metre high. Now, with 125 metre turbines the norm and turbines of up to 200 metre being built. The wind turbine industry routinely proposes building turbines within 500 metre of housing.

Press release from Infinis regarding the Ardrossen wind farm fire, 8 December 2011: “As a standard precautionary measure, all Infinis staff vacate wind farms when wind speeds exceed 55 mph and therefore no one was present on site at the time of the incident.”

A 30 metre turbine near Coldingham was deliberately collapsed by its constructors, Maden Design and Build, after going out of control on Wednesday, 7 December, 2011. Lothian and Borders Police said "The turbine suffered brake system failure and had been free wheeling in 50 mph winds. Nearby houses had to be evacuated and the A1107 shut." The turbine had only been operational for a short time. 

Wind turbines standing idle on the edge of Alnwick will not be repaired by the manufacturers, with the tax-payer likely having to foot the bill to get them working again. Town councillor Sue Allcroft has been chasing the Department for Environment, Food and Rural Affairs (Defra) over the three generators at its flagship Lion House, which have rarely turned since mid-2010 following a worldwide recall of the that model – the P35 – by their Scottish-based manufacturer, Proven Energy. Proven finally went bust last September, but was sold by receiver KPMG to Irish renewables firm Kingspan Wind. However, Kingspan’s website states that all liabilities and warranties for P35 turbines remain with KPMG, as they did not form part of the buy-out deal.

Then I read "Spinning to destruction" by  Michael Connellan in the Guardian. "Wind power may be one of the cleaner, greener energy sources available, but turbine and blade failures point to dangers that were not anticipated."

BBC News, 6 June 2012. Design snag causes wind turbine shut-down. "The owners of a French-made wind turbine have been advised to keep people away from them after bits started falling off. The Northern Ireland Health and Safety Executive gave the warning and advised the 17 owners to lower the turbines the ground. The warning came after the blade assembly fell off several machines."

There is always one! The Telegraph reported Dale Vince of Ecotricity as being assiduous in spreading the silly story that the turbines which suffered catastrophic blade failure at his Conisholme power station might have been struck by a UFO or some other mysterious external agent: "It was Mr Vince's willingness to consider paranormal explanations that drew attention to the UFO theories and he told the Telegraph he was disappointed by the results of the tests." Other causes of the damage mooted at the time included aircraft, frozen urine dropped from a passenger jet and – least plausibly – collision with a flying cow.

Mr Dale Vince of Ecotricity has no connection with your favourite inland waterways charity!

Later....