Alaska Village Electric Cooperative (AVEC) constructed a wind power project in the village of Emmonak in 2010 that is comprised of six Northwind 100 B model turbines for 600 kW of installed wind turbine capacity, an electrical intertie to the nearby village of Alakanuk, and a control system to integrate the turbines to the existing power system. In anticipation of this project, a met tower was installed in Emmonak in July, 2007 to collect wind data. In addition to wind data, AVEC collected other information such as electric load and diesel power plant performance data for Emmonak and Alakanuk. This data was analyzed with software tools to evaluate the wind resource itself and to predict the performance of wind turbines and their operation as a wind-diesel hybrid system once connected to the village’s existing power system. The Emmonak met tower site was located on the tundra in a clearing of willow trees just west of the village boundary. This site was selected based on the intended location for wind power development and consequently turbines were installed nearby.
The wind resource measured at the Mountain Village met tower site is very good with measured wind power class 5 (excellent). In addition to high average wind speeds and high wind power density, the site experiences very low turbulence and low extreme wind speed probability. Its location on a high exposed plateau above the Yukon River makes it ideal for wind power development.
The wind resource in Eek is estimated based on wind studies completed in the nearby communities of Quinhagak, Bethel, and Kongiganak. The wind resource in Quinhagak was measured from October 2005 to May 2007 with a 30 meter met tower located near the site of the recently-constructed wind turbines. The mean wind speed in Quinhagak (at 30 meters) was measured at 6.3 m/s with calculated wind power density of 338 W/m2. Quinhagak classified as IEC Class III-c.
Other data sources, including a March 2006 AEA Report (M. Devine) for Chefornak, indicate mean annual mean wind speed in Bethel as 6.9 m/s and Kongiganak as 7.3 m/s. The Bethel and Kongiganak data indicated similar Weibull k, turbulence and wind shear values as Quinhagak. Given that a met tower study has not been conducted in Eek, but the referenced communities of Quinhagak, Bethel and Kongiganak bracket Eek in three directions and share similar topographic features, the referenced data sources are thought highly representative of Eek’s expected wind resource. Of the three referenced communities, the wind data in Quinhagak was selected to represent Eek as it exhibited the lowest average wind speed and hence is most conservative. The actual wind resource in Eek may be stronger; closer to that of Kongiganak. If true, energy production from the proposed wind turbine would be higher than estimated in this report.
AVEC has proposed construction of wind turbines near the village of Marshall to augment the diesel ge-nerators and create a wind-diesel power system. Although abbreviated by a failed anchor that led to collapse of the met tower, the Marshall wind study indicates a Class 3 to 4 wind resource with accepta-ble turbulence characteristics and extreme wind probability for wind turbine operation.
Saint Mary’s, Alaska is the largest village on the lower Yukon River and a high priority wind power project site for Alaska Village Electric Cooperative (AVEC). In addition to the existing electrical intertie between Saint Mary’s and Pitka’s Point, current plans calls for continuation of an existing intertie west from the Saint Mary’s Airport to Mountain Village and possible future construction of an intertie east from Saint Mary’s to Pilot Station.
Nightmute has an outstanding wind resource for wind power development, characterized by a high average wind speed, high wind power class, and low turbulence. Nightmute’s wind resource is higher than other wind resources measured in the area, perhaps due to funneling of winds around the very high (839 ft elevation) Toksook hill immediately north and behind the village.
The Mekoryuk wind test site has outstanding potential for wind power development with Class 6 winds, low wind shear, and low turbulence. The wind rose indicates more variability in wind directions than observed elsewhere, but this likely is a consequence of Mekoryuk’s coastal location and maritime climate influence. For a representative village-scale stall controlled turbine and pitch controlled turbine, both yield low thirty percent capacity factors at 32 meter hub heights. An expected challenge with wind turbine operations in Mekoryuk is the occasional extreme low winter temperatures and consequent high air densities experienced.
Chevak has an outstanding wind resource for wind power development. Not only does the site rate as Class 6 (of seven designated classes of wind), the winds are relatively directional and low turbulence. Besides logistics and construction issues, the one significant challenge to installing wind turbines in Chevak is the permafrost soils at the designated wind farm site.