Nome utility to remove all small turbines from wind farm

By Maisie Thomas

Nome Joint Utility System is planning to remove all 15 of their 50 kilowatt Entegrity turbines from Nome’s Banner Wind Farm this year. The turbines will be taken down because they are “obsolete,” said NJUS Assistant Manager Ken Morton. The majority of energy produced by the wind farm comes from NJUS’s two 900 kW EWT turbines. 

A cost-benefit analysis of maintenance versus energy production tipped in favor of shutting the smaller turbines down, Morton explained. “The cost to maintain the smaller units has increased to the point that the cost of the diesel fuel they displace no longer pencils out,” he said.

Banner Wind Farm, named for its location on Banner Peak, became operational in 2008. NJUS took over operations from Bering Straits Native Corporation and Sitnasuak Native Corporation a few years later, and installed the larger turbines in 2013. The smaller turbines are original to the farm, and according to Morton, not as robust as the 900 kW units. 

Due to their age, the control components for the turbines are no longer available and the brake tips require “significant” servicing. Moreover, NJUS has been unable to find replacement turbines for the smaller units; 50 kW is “just too small for the market.” NJUS has budgeted $20,000 for turbine removal.

Morton said that NJUS does not at this time have plans to replace the turbines or add additional ones. However, if grant funding becomes available for additional turbines, as well as funds for a battery system that would allow for greater reliance on wind energy, NJUS would pursue that. 

According to the NJUS Production Report for December 2020, Banner Wind Farm produced 431,035 kilowatt hours, which accounted for about 14 percent of energy production during the month. All of this was produced by the two EWT turbines. The net capacity factor for the two EWTs is 29 percent. Net capacity factor is defined as the ratio of net electricity generated in a time period to the amount of energy that could have been generated at continuous full-power operation. 

According to Morton, on a windy day (of which Nome has many), the farm can generate up to 35 percent of Nome’s power. The yearly average, though, is much lower, at nine percent. In 2019, wind energy displaced 155,000 gallons of fuel, which equates to roughly $360,000. 

Due to the amount of wind the Bering Strait region receives, the area is prime for wind power. According to a report from the Alaska Energy Authority, wind energy is measured according to a scale from one to seven, with one being poor and seven being superb. The majority of the Bering Strait region ranges from Class 4 to Class 7 winds. 

However, there are a number of challenges to operating and maintaining wind turbines in rural northwestern Alaska. In its roughly 12 years of operation, Banner Wind Farm has suffered several blows. Originally, 18 50 kW turbines were installed, but over the years three have been removed. A particularly dramatic example was in 2014, when a windmill fell down and was completely destroyed. According to a report by the University of Alaska Anchorage’s Institute for Social and Economic Research (ISER), shortly after the turbines were installed in Nome, the blade pitch needed to be adjusted to compensate for increased density of the colder winter air. For a number of reasons, including extreme weather conditions, it took roughly four months to complete the adjustment. Then, a serial defect in the turbine’s drive trains was discovered. As a result, all the turbines had to be shut down again for another four months, until August of 2009. Banner Wind Farm started producing power in September 2009, close to a year after the turbines were installed. 

Nome began its efforts to install turbines in early 2008; the turn to wind power coincided with an increase in the cost of diesel fuel and thus a rise in the cost of power, according to a 2017 report by the Alaska Center for Energy and Power (ACEP). “...The energy crisis facing rural Alaska has reached unsustainable levels that threaten the health, security and abilities for residents to maintain the basic necessities of life…” reads the grant application referenced in the ACEP report.