Extracts from the March-April 2003 edition of Renew
These extracts only represent about 25% of it

7. Wind Unreliable

With the wind versus nuclear debate hotting up, Prof. M Laughton waded in with critical comments on the reliability of wind arguing that the intermittency of wind power made it difficult to integrate large amounts into the grid system and maintain firm supplies, unless there was extra, expensive, back up capacity. In a paper in Power in Europe 363 (Sept 9th) he comments ‘Large high pressure systems with little wind pass over the country or parts of the country throughout the year. Those occurring in the winter are invariably accompanied by low temperatures, frost and fog, the occasions when heating and lighting loads can also be at maximum i.e. at winter peak load times. Electrical power has to be available, so wind power capacity has to have 100% back up.’

Laughton claims that if we had 7300MW of wind capacity, which is what’s expected on the current programme by 2010 (with wind supplying about half to 10% target), the practical output could ‘vary from 73000 to practically zero’ and that going further, to a 20% target by 2020 as the PIU suggested, would ‘prove intolerably expensive’ given the need for 100% back up.

The problem with this analysis is that it ignores the fact that all power stations have down times and the grid system is run with a substantial overcapacity (currently 25%) to compensate, with it being very rare that all of it is used at any one time. Some is kept as spinning reserve, ready to deliver power at short notice if demand rises, and this can cope with most variations in demand and supply. In extreme weather conditions some other standby plants may be brought into play for short periods. With wind on the grid, all that would happen is that this might happen more often, and, depending on how much wind plant there was, there might be a need for more standby plant. But it would not be a case of matching all the wind capacity 100% with extra standby plants. Laughton seems to admit this when he says that since wind cannot provide 100% guaranteed peak load, ‘the peak load margin has to be covered by conventional plant as at present’.

Of course, if variable sources like wind are to make a large contribution, beyond 20%, we could need some more peak load plants, and some extra storage capacity. But by then we will pressumably be moving into the hydrogen economy, and the whole situation will look very different. However, we may not need to wait until 2020 to find out. Denmark currently obtains about 18% of its electricity from windturbines, and on occasions in some area during low demand periods at night, all the other power plants are run down, so that wind is providing base load. Loughton however argues that Denmark is only able to cope with its large and variable wind input because it imports firm power from Norway and elsewhere. But then some of that is renewable i.e. Norwegian hydro, and interconnections like this are clearly one way to balance local variations. The debate continues.

MOD on Wind

In response to Parliamentary Questions on the impact of Ministry of Defence policy on radar coverage and low flying upon the Government's policy to expand wind energy technology, Dr. Lewis Moonie noted that ‘since 1 January 2000, the Ministry of Defence has objected to a total of 284 wind energy proposals, but has had no objection to over 400’. He added ‘The MOD is acutely aware of the government’s stated aim to achieve 10 per cent. of the United Kingdom’s energy from green sources by 2010 and makes every effort to assist in achieving this’. However, he went on ‘the Government is also committed to maintaining flight safety and the operational effectiveness of the Armed Forces. Ministry of Defence officials are currently involved in a steering group with the Department of Trade and Industry, Civil Aviation Authority, National Air Traffic Services and the British Wind Energy Association. The group aims to address some of the issues that lead to the MOD and others making objections to developers’ proposals. The MOD is currently assisting in a DTI-sponsored project by QinetiQ to study the effects of turbines on radar’.

Electricity Market crisis Wind is the problem!

Some people in the power industry seem to believe that the main reason for the UK’s electricity market crisis, which last year saw BE face collapse and put TXU’s UK wing into administration, is generation overcapacity. With the power market under the old pool system favouring generation, many more plants were built than can survive under the new more competitive post-NETA arrangements. And new wind farms could exacerbate the problem.

‘The outlook is for the capacity surplus to grow as more wind and CHP (combined heat and power) plant is connected in response to the government's incentives for renewable energy sources.’ So said Callum McCarthy, chief executive Ofgem, at an industry conference recently.

Ofgem suggest that if the UK’s targets to expand renewables are met, and all existing power plants run to the end of their projected lives, then the surplus capacity would grow from the current 25% over peak demand to about 60% in 2010. So far around 2GW of conventional capacity had been mothballed, but that has made little difference to price levels, which are still low.

See our Reviews section in Renew 142 for IPPR’s discussion of the options- which they see as including phasing out of coal fired plant to reduce both emissions and overcapacity. Also see Sec 13 below.

Ford go for wind in London

Ford is to convert part of its former car plant at Dagenham in Essex into London's first wind farm. It will consist of three 1.8 megawatt turbines, and is due to start operating in June, to coincide with Ford’s centenary as a UK car maker. It will generate enough electricity to meet all the needs of the 473-acre site, which is now Ford’s prime European location for diesel engine production. The windfarm is being developed in partnership with Ecotricity and in seen as making an important contribution to the pledge by the Mayor of London, Ken Livingstone, to cut carbon dioxide emissions from the capital by 10,000 tonnes a year. Dale Vince, managing director of Ecotricity, told the Independent (25/9/02) that he did not expect any local opposition. "This is an industrial site so there is no question of anyone’s view being blighted. The early windfarms in places like Cornwall had noise problems but today’s technology means that is no longer an issue."

Designed by Sir Norman Foster, the three turbines will cost £4m. One will have a 65-metre high public viewing platform which Ford claims will rival the London Eye for its views down the Thames. The viewing gallery at Ecotricity’s first major windproject at Swaffham in Norfolk, has so far attracted 50,000 visitors.