February 17, 2012
CRN TechCurve: Electric generation from renewables like wind and solar is making dramatic inroads in many areas of the United States, with some utilities reporting penetration levels of 30 percent or higher on individual feeders. But as these variable power sources continue to expand their presence on the nation’s electric grids, power companies are seeking new and better ways to address the challenges of system integration and stability.
As is often the case with grid innovations, electric cooperatives in Alaska are ahead of the curve. Kotzebue Electric Association (KEA), a 1,200-member system located 30 miles above the Arctic Circle, has been steadily adding wind turbines to their power mix over the past decade. They currently generate 1.1 MW, or more than 40 percent peaking load, from wind. The remainder is covered by diesel generators. This spring, they’ll take their power mix to another level by adding two 900-kW turbines which will give the co-op 2.9 MW of wind power, more than 100 percent of average load. But, KEA still faces the challenge of harnessing the energy from this intermittent generation source. As part of the solution, KEA has taken a ground-breaking step: the installation of a TransFlow 2000, a huge zinc-bromide flow battery system that will allow the co-op to better balance its wind and diesel generation. Read more