How green are wind farms?

The 'green' movement, led by Greenpeace, greeted the UK government's announcement this week that it was to build huge wind farms with almost universal approval. But how 'green' are wind farms?

Wind energy is, of course, renewable, but the turbines themselves are created from non-renewable resources, and being such huge structures, they require huge concrete bases to anchor them. Concrete is a pretty energy intensive material, and the placing of the bases may well affect natural drainage patterns. But to me, as a naturalist, the most worrying feature about wind farms is the death and destruction they can and do mete out to wildlife. Now, not all wind farms or individual wind turbines kill wildlife. But many do, and some on a very significant scale. I have been reading about a Spanish wind arm in Navarre that has killed hundreds of the threatened Griffon Vultures. It has also killed over 600 bats in a year, as well as thousands of small birds and other endangered species such as White Stork and Bonnelli's Eagle. In California, there are serious concerns about the impact of wind farms on the local Golden Eagle population. And flying around the Internet there are accusations that data about wind farm mortalities is being suppressed.

Gathering data on the mortalities at wind farms is difficult, but the fact that they kill birds is incontrovertible. Nearly all large man-made structures from pylons, power-lines, oil rigs, skyscrapers are hazards, killing large numbers. But add to those structures blades whirring around with a wing-tip speed of nearly 150mph (240kph), and there is a serious hazard for all but the most agile of birds and bats. And for less manoeuvrable species - such as eagles and hawks, collisions often become inevitable.

Birds and bats killed or even injured by wind turbines fall to the ground, and in turn may attract predators, so gathering data becomes difficult. And the predators attracted, may in turn become victims. But research has been carried out to calculate these losses, and this indicates that some of the estimates may well be too low. And of course collecting data at sea is even more difficult.

Far too little is known about the likely impact on wildlife populations of the proposed wind farms in Europe, and the enthusiasm for them by some environmentalists may well be entirely misplaced if they endanger birds and bats. But once they are built, just like the nuclear power stations, it will be very difficult to get them shut down, however many birds the kill. And the problem seems to be compounded by the fact that the wind power promoters are now funding many conservation organisations, including the RSPB. This has led to critics of the wind farms accusing such organisations as not being objective. The time has surely come for a really objective look at the environmental impact of wind farms. David Bellamy and I have been looking at this issue and trying to find out what the real effects will be - clearly renewable energy is something we all support, but what if the costs, in terms of other impacts on the environment are too high?

My concern is that the energy companies (whose main raison d'être is to sell more and more energy) are promoting wind farms because they have convinced the environmentalists that it is totally safe and renewable. The environmentalists are more concerned with being anti-fossil fuels than really considering the environmental impacts of wind farms. And it is the wildlife that will miss out- yet another straw on the donkey's back.

Feedback will be welcome.