Kotzebue Electric Association, a cooperative located 33 miles north of the Arctic Circle, is continuing to lead the way with its innovative hybrid generation system that combines solar, wind and battery storage with baseload diesel power.
The newest addition is a 576-kW solar array using “bifacial photovoltaic panels” that not only capture energy directly from the sun, but from light reflecting off the ground or throughout most of the year from the snow on the ground.
“We actually have our highest production in the (spring) months when we have snow on the ground or through,” says Project Engineer Matt Bergan.
A solar array may seem an unlikely source of power in a region where the sun doesn’t come up from early December to mid-January. But Michael Leitman, NRECA’s system optimization director, notes Kotzebue’s use of cutting-edge solar with wind as an example of how co-ops are finding creative ways to take advantage of hybrid generation.
“Battery-plus-solar is most common,” Leitman says. “But we’ve seen a variety of renewable technologies as well as fossil generation adopted. They offer great potential by combining complementary resources like wind and solar, whose different daily and seasonal production profiles can increase daily output and reduce intermittency when combined.”
In recent years, it has retired aging turbines and shifted some generation to solar, which requires less maintenance and provides a seasonal balance, with wind strongest in the colder months and solar in summer and spring.
Kotzebue now gets 25% of its power annually from renewables, although some days it can reach 80%, Bergan notes. The co-op’s 950-kWh lithium-ion battery is used to smooth out fluctuations from renewables. As Kotzebue reduces its dependence on diesel fuel, Bergan sees a bright future for the hybrid approach.
“We have plans to expand all of it.”