Why a wind turbine at Eden?

With the climate going haywire, and energy security rising to the top of the agenda, we want to do our bit. The turbine will supply clean electricity for us to run our own operations, and to feed some into the national grid. Eden will become a contributor to the national electricity resource.

In 2006, only 1.5% of the UK’s energy was supplied from renewable sources. The EU has proposed that we should ramp up this supply tenfold by 2020. This is described by the government as a ‘very challenging target’ and three times more than current policies are designed to achieve. Onshore wind development will be a very important part of the mix, as it is a relatively mature industry with well-proven technology and known costs, when compared to other renewable technologies such as wave, tidal or solar. For more information about the government’s energy strategy see http://renewableconsultation.berr.gov.uk/.

Eden is an environmental educational charity, and we try to walk the talk throughout our operations and business practice: from how we build our buildings to where we source our food, or deal with our waste. Although we have been signed up to a green tariff electricity supply for years, the twin problems of energy security and climate change are now so compelling that this is simply no longer good enough. We want to do our bit by increasing renewable electricity supplies.

The turbine will be a focus for exhibits about energy and climate change, and we hope that the experience of putting it up while balancing the social, economic and environmental implications, and trying to maximise the benefits to the local community, will give us valuable insight into the process that we will be able to pass on to others. Eden Clean Energy is part of our Climate Revolution programme (http://edenproject.com/what-we-do/climate-revolution/index.php).

Why a single big turbine?

We anticipate, subject to ongoing technical investigations, choosing a 2MW model, 80m tall to the hub and with a blade length of 45m. The total height will be 125m. There are several reasons for looking at this model.
• Bigger really is better when it comes to wind turbines in terms of their efficiency, as the wind power intercepted by the turbine is proportional to the square of its blade length. Double the blade length, and you can quadruple the power !
• Similarly, the power available is a function of the cube of the wind speed, so a site for the turbine where the wind speed is 8 metres per second will produce on average 75-100% more electricity than one where the wind speed is 6 m/s. Wind speed increases with height above the ground, so taller is better too.
• A turbine of any size should be at least 450m away from the nearest house. Although on a rural site, Eden is surrounded by houses, so this limited our choice of sites on our own land to two… and one of them is down in the pit, and not suitable for catching wind. So that left a single plot, which is only big enough for one turbine.
• Putting up wind turbines is an expensive business (more than £1.5m a megawatt), and to make it stack up for the bank, we’ll have to produce as much electricity as possible.

Want to know more?

Find out more about Eden's Climate Revolution Programme

For more information about the government’s energy strategy see http://renewableconsultation.berr.gov.uk/