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The world's largest wind farm was opened on 23 Sept 2010 by Chris Huhne, the Energy and Climate Change Secretary.
It has cost £780 million to build. It increases the UK's offshore wind energy "rated capacity" to 1.34 gigawatts.
Because of the intermittency of wind, the amount of electricity actually generated most of the time will be a small fraction of this - less than the output of one conventional power station. Nevertheless Chris Huhne wants 15% of UK electrical energy generating from what he calls 'clean' sources a decade from now. Regardless of cost or effectiveness, it seems.
The strategy is flawed, as regular visitors to this site will be aware. These heavily subsidised turbines do not replace a single conventional power station. If there is no wind, they produce nothing; a 'spinning reserve' of coal or gas turbines has to be available 24 hours a day, running synchronously with the mains but producing no power, so they can 'cut in' if the wind drops. This is the most inefficient way of running a turbine.
If the wind is blowing when the power is not needed - for example, at night - the power is wasted because it cannot be stored. This means that the turbines typically operate at a very low efficiency. It is not surprising that the Germans and the Danes are building no more wind turbines. In contrast, a natural resource which is completely reliable (the tides) is hardly exploited. Plans for a Severn Barrage, which would produce perhaps 5% of the UK's energy needs, are being abandoned following a feasibility study.
Renewables for the foreseeable future will have a marginal impact on our energy supply, other than driving up the prices we pay for our electricity.
In the short to medium term we need more nuclear power stations, particularly in view of the Large Combustion Plant Directive, which will lead to a significant fraction of our older coal fired power stations (still perfectly serviceable) being shut down over the next few years.
It will be interesting to see how long it takes the new nuclear stations to appear. It is worth reminding ourselves of the current contributors to Europe's electricity supply:
Nuclear 31%, Coal 30%, Gas 20%.
and thinking about what is happening now to the price of gas, coal and oil.
Some of you may be unaware that there is also a 'renewables obligation'. Energy companies are obliged to buy a certain proportion of renewable energy from wind farms, regardless of price.
The costs incurred are passed on to the consumer. It amounts to an invisible surcharge on electricity - a sizeable fraction of what is paid for heat and light. A recent article in 'The Economist' suggested that it's 14% of your electricity bill.
There is no evidence that this will have a beneficial effect on the world's climate.
In addition to this, £18 billion per year is being committed to 'decarbonising' the economy.
This is equivalent to £700 per houshold.
This will appear not as invisible energy surcharges but increased taxes.
ND, habitat21
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