One of the conundrums of wind energy is that the wind doesn’t blow constantly. In the Northwest, most wind farms operate at about 30 percent capacity, which means backup electrical generation is needed.
The Northwest’s extensive network of hydropower dams helps balance fluctuations in wind output, said Tom Karier, Washington representative on the Northwest Power and Conservation Council. Dam operators can adjust hydro output in response to shifting wind production.
But problems arise in late spring and early summer, when peak runoff from snowmelt coincides with peak wind production. In high runoff years, the region is awash in surplus hydro power. Prices can plummet to very low levels. Some years, the Northwest gives away electricity from federally owned dams, and adding wind generation “aggravates the situation,” Karier said.
Last summer, the Bonneville Power Administration ordered wind farms to shut down their power output at times when Columbia River reservoirs were brimming and dams were operating at maximum capacity.
Wind farm operators appealed to the Federal Energy Regulatory Commission, which ruled in their favor last week. Federal officials said the BPA must come up with new rules that don’t discriminate against wind generators, which lost about 6 percent of their potential power sales between mid-May and mid-July.
Karier said efforts to find equitable solutions are already under way. He and BPA Administrator Steve Wright co-chair a group called the Wind Integration Forum.
“Every day, the hydro system is adapting to changes in wind that occur on an hour-to-hour, minute-by-minute basis,” he said. “We’re able to absorb and use wind power much more efficiently than many other parts of the country.”