Last month, the Conservative government joined the long line of governments around the world subsidizing the production of wind power. Meanwhile, new information about wind power from Europe raises the spectre of unexpected blackout risks, high costs, unreliable production and even questionable environmental benefits.
Concerns over wind power used to focus on whether enough wind would blow to keep wind generators busy and electric power grids supplied. Now, after a major power blackout in Europe in November that left 15 million households in the dark, concerns over wind power come from an entirely opposite direction ““ fear that wind power can unpredictably produce more power than a system can handle.
The blackout started late on a Saturday night during a spell of warm fall weather. Although consumer demand was low, wind-power production in northern Germany was very high, supplying about 14% of the total and flooding the northeast region of the European grid with unexpected volumes of power. Meanwhile, most coal- and gas-fired generators, which can act to moderate erratic production elsewhere on a system, were either out of service or operating at a reduced output.
Grid operators then miscalculated the consequences of a routine grid manoeuvre: They disconnected a high-voltage line to let a ship pass though a canal. Overloaded power lines automatically disconnected, causing the blackout to sweep across Europe and forcing massive amounts of generation to automatically disconnect from the grid.
As operators attempted to restart the grid, wind generators, which are out of the direct control of the grid operators, automatically reconnected to the grid. They injected unwanted power and caused further disruption, extending the blackout in the areas with the most wind power.
To prevent a reoccurrence, the European agency responsible for power-grid reliability, the Union for the Co-ordination of Transmission of Electricity (UCTE), studied the blackout and recommended several remedies.
One recommendation would require upgrades to wind-power systems to allow grid operators to directly control these generators. This measure will increase the cost of connecting wind generators to the grid, but another recommendation ““ massive investments in the transmission grid ““ would hit harder. Much of Europe’s power grid was originally designed primarily for local generators serving mostly local customers. Now, moving large amounts of wind power vast distances during periods of high wind generation, which exceeds the needs of local customers, has overstretched the system. New high-voltage power lines that will be both controversial and costly are now in the cards.
Across the English Channel, the wind blows cold for other reasons. Although the U.K. has the highest wind-power productivity of any major wind-power country in Europe, its production falls short of the generally accepted minimum threshold for viability. A case in point can be seen in the U.K. government’s five-year anniversary review of its renewable energy subsidization program, called Renewables Obligation (RO), which disproportionately supports wind power. Tellingly, it has heard from the Office of Gas and Electricity Markets (Ofgem), the regulator mandated to protect consumers with respect to rates and reliability. Ofgem has major concerns.
The Renewables Obligation was intended to promote technology, but the regulator observes that “there is little evidence so far that the RO is encouraging technological development.” As a result, consumers have been jolted. “The cost of the scheme to both business and domestic electricity customers has been very high ““ over ?1.7-billion [$3.8-billion] to date,” Ofgem states. Taking into account that the rate impact is growing rapidly from a relatively small initial cost, the regulator goes on to estimate that the ultimate cost may balloon to over ?30-billion.
As for environmental benefits, the regulator observes that “there are currently much cheaper ways of reducing carbon emissions from the electricity sector than the RO scheme.”
Some environmental organizations are raising substantive concerns, too. Two engineering analyses of the wind-power experience in the U.K., commissioned by a prominent environmental organization called the Renewable Energy Foundation and released before Christmas, turned up problems producing practical electricity supplies from the wind.
The engineers found that wind power production is a mismatch to power needs – in winter at times of low temperatures, when the U.K. needs power more, wind speeds tend to be low; when temperatures are high and it needs less power, in contrast, wind speeds are high. Across Europe, the output of wind power facilities is generally lagging the originally forecasted output.
Canada’s experience in wind production shows the same patterns. Worryingly, detailed production data from Ontario’s largest wind farms in November, December and January also shows the same mismatch between the availability of wind power and our need for it.
Canada’s experience with wind power has likewise been disappointing. Of the 14 wind farms receiving federal subsidies that have operated long enough to reveal a clear picture of their productivity, 12 have failed to achieve their forecasted production. Two of the federally supported wind farms have failed to match half of their forecasted production. Overall, the 14 wind farms have produced 18% less power than expected. Likewise, provincially subsidized windmills have also been failures.
Yet wind also has had successes. When sited properly, they can be contributors to the country’s grid system, and with more knowledge about how the wind works, we doubtless will one day see wind systems that are both economical and reliable. Until then, the answers are blowing in the wind.
by Tom Adams
22 February 2007
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