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Market players are already responding with solutions to the problem of retaining the benefits of aggregated power systems while breaking the market down into many participants to promote competition. The problems caused to wind plant operators by forcing every supplier to match generation with demand -- as is happening in Britain under its new electricity trading arrangements (NETA) -- can be lessened if operators team up or use an aggregator.

In Britain, Concert Energy is offering aggregation and a similar service -- albeit for backup generation -- is to be tested in New York State by Electrotek Concepts. Electrotek's aim is to demonstrate the aggregation of dispatchable backup generators to provide efficient energy and ancillary services in the New York electricity market.

Another way in which wind operators can ease the lot of system operators is to provide accurate forecasts of their output. Almost every country with a wind program is working on this and the accuracy is steadily improving, but it is difficult to forecast short-term fluctuations.

A technical solution, which improves the overall efficiency of most electricity systems -- and therefore decreases emissions -- is the provision of additional storage. It rarely makes sense to build storage specifically for wind plant (“uåX˜äŠÊ˜·³Ç, October 2000), but availability makes wind easier to assimilate. Demand-side management is another tool, which works in a similar way to storage as it enables surplus wind generation to be absorbed. Such management is likely to gain in importance as power system control becomes increasingly sophisticated.

Once the capabilities of existing storage capacity have been reached, there are just two more technical solutions left. One is to schedule more thermal plant to run at part load, or to wait on "hot standby." The extra costs to the electricity system are easy to quantify and are not excessive, but it is likely that differences will arise between the "technical" cost and the market cost, perhaps making this option not as attractive as it should be. Another is to require wind plant operators to restrict their output. This, again, has a quantifiable cost and may, in some circumstances, be a preferred option.

Construction of additional peaking plant specifically to increase the reserves on systems with high wind penetrations seems an expensive solution compared with the other technical options. It would only become a preferred solution in systems where there is a shortage of flexible generation.

Transmission constraints may narrow the choice of options for balancing supply and demand: if the economics suggests that surplus wind should be used to charge a pumped storage scheme, but that scheme is remote from the wind generation, transmission constraints will come into play.