MORE THAN ENOUGH CLEAN POWER TO MEET OUR NEEDS

Letter submitted to The Independent, 2010-09-06, and published 2010-09-07.

Dear Editor,

Steve Connor is quite right to say that numbers, rather than vague statements, are important in considering future energy supplies ("Why achieving a cleaner energy economy involves a series of difficult choices", 3rd September). But numbers that are available from reputable sources belie his pessimistic assessment of renewable sources of power.

A report by the Offshore Valuation Group estimates that the practical potential of offshore generating technologies in waters around the UK is 2,131 TWh/year -- nearly six times current UK electricity demand.

In another report, the European Environment Agency estimates that the "economically competitive potential" of wind power in Europe is 3 times projected demand for electricity in 2020 and 7 times projected demand in 2030. Offshore wind power alone could meet between 60% and 70% of projected demand for electricity in 2020 and about 80% of projected demand in 2030.

A paper published in the Proceedings of the National Academy of Sciences of the United States of America shows that a network of land-based 2.5-megawatt (MW) turbines restricted to nonforested, ice-free, nonurban areas operating at as little as 20% of their rated capacity could supply more than 40 times current worldwide consumption of electricity and more than 5 times total global use of energy in all forms. There is additional potential in offshore wind farms.

Researchers at the German Aerospace Centre have calculated that, using the proven technology of concentrating solar power (CSP), less than 1% of the world's deserts could generate as much electricity as the world is using now. It is feasible and economic to transmit that electricity for 3000 km or more using low-loss HVDC transmission lines. 90% of the world's population lives within 2700 km of a desert.

Research that is reviewed in the November 2009 issue of Scientific American shows that renewable energy technologies can provide 100 percent of the world’s energy (not just electricity) and that it is technically feasible to make the transition by 2030.

Contrary to what Steve Connor suggests, nuclear power stations cannot be relied on to provide a steady 'base load'. Like any kind equipment, nuclear power stations can and do fail. And when they fail they create a particular problem because, normally, a relatively large capacity is lost quite suddenly and without warning. By contrast, sources such as wind power normally decrease gradually and there are normally several hours warning. Fortunately, both kinds of intermittency can be accommodated: there is a range of techniques available for matching variable supplies of electricity to constantly varying demands.

It is true that decarbonisation of the economy will cost money but not as much as one might think. A recent report from the European Climate Foundation found that in several scenarios, including the generation of electricity from 100% renewable sources, the future cost of electricity is comparable to the future cost of electricity under the current carbon-intensive infrastructure -- and supplies would be at least as reliable.

Sincerely,

Dr Gerry Wolff PhD CEng

Energy Fair