Bluff and bluster: The campaign against wind power

Reliability of Wind Power

Opponents of wind power often claim erroneously that, as an “intermittent generator”, wind power cannot be run as base-load to replace coal-fired power stations and cannot contribute to peak demand without expensive dedicated long-term storage. Since no-one is proposing to run a whole electricity grid on wind power alone, these claims are simplistic. In each of our State studies (pdf file 435KB), the clean energy mix substitutes separately for both the contributions to peak-load (as measured by Equivalent Firm Capacity or Effective Load-Carrying Capability) and to base-load (as measured by annual electricity sent out) of a coal-fired power station.

One critic of wind power claims that a single heat wave in western Europe, during which there was little wind, demonstrates that wind power is unsuitable for providing electricity to the grid. But, if this argument were valid, then a single breakdown of a coal-fired power station would also rule out coal. In practice all types of power station - fossil, nuclear and renewable - are only partially reliable and all require some backup. Coal-fired power stations break down less frequently than there are calms in the wind, but when a coal station breaks down, it is generally out of action much longer than a typical wind calm.

Therefore the comparison of the reliability of wind and coal power cannot be done deterministically, based on a single peak event. The correct approaches consider the effects of three different probability distributions:

• the availability of coal-fired power stations;
• wind power; and,
• electricity demand.

These are then combined with the use mathematical and or computer models to calculate the reliability of electricity grids with different penetrations of wind power.

This was done by a multidisciplinary research team in CSIRO and ANU in the 1980s. Three different methods gave the consistent result that wind power is indeed partially reliable. It has economic value in substituting for the capital cost of coal-fired power stations, as well as for the fuel burnt in such stations. These results were confirmed by overseas researchers.

For the special case of small penetrations of wind power into an electricity grid, the value of wind power as “firm” (i.e. 100 per cent reliable) capacity is equal to the annual average wind power generated. As the penetration of wind power into a grid becomes very large, the value of wind power as “firm” capacity tends towards a limit. At a wind energy penetration of (say) 20 per cent, some additional peak-load (hydro or gas turbines) is indeed required to maintain grid reliability. But this peak-load plant is only a fraction of the wind capacity and does not have to be operated frequently. It is equivalent to reliability insurance with a low premium. And it does not diminish significantly wind’s reduction of CO2-emissions.

Who gains from attacks on wind power?

In the UK, the umbrella organisation opposing opponent of wind power is called Country Guardian. At least until recently, one of its top office-bearers had a close relation to the nuclear power industry, which is being pushed forward as a possible competitor for renewable energy in reducing greenhouse gas emissions from electricity generation.

Australia generates about 84 per cent of its electricity from coal, the highest percentage after Poland and South Africa. Clearly the coal industry and possibly one of the largest users of (subsidised) coal-fired electricity, the aluminium industry, would benefit from the anti-wind power campaign in Australia.

Incidentally, my own connection with wind power is that I was leader of the CSIRO/ANU wind power research group mentioned above. I am not being paid for writing this article.

Conclusion

Wind power is one of the most environmentally benign of all energy sources. Anti-wind power groups that exaggerate environmental impacts and technical limitations should be scrutinised for possible funding from industries that stand to gain from attacks on wind power. Like conventional sources of electricity, wind power is partially reliable and, with a small amount of inexpensive backup, could contribute 20 per cent of Australia’s electricity. In Denmark, where wind power already contributes 20 per cent of electricity, there is very little community opposition. Danes generally support wind power as an environmentally sound, job-creating technology that has already substituted for some coal-fired power stations. But, Denmark does not have its own coal resources and it has rejected nuclear power.