Healy Wind Study

Final Update

Effective June 2001, Golden Valley terminated the Healy Wind Demonstration project due to gunfire that caused damage to the tail and the blades. This damage occurred just as the original contract was about to expire. Although the agreement could have been extended and the wind turbine repaired, GVEA decided to conclude the project because of the damage to the wind turbine, concerns about the effects of vibration on the communications tower and poor reliability of the conversion electronics. The wind turbine operated from September 1998 through October of 2000. From October 2000 until June 2001, it was out of service waiting for repairs to equipment that failed or was vandalized.

Although GVEA has terminated this project, we continue to evaluate wind resources for commercial scale wind production in Interior Alaska with the help of independent contractors.

Project participants

In 1998, GVEA joined Alaska Wind & Solar (AKW&S) in a wind generation demonstration project in the Healy area. AKW&S received a $25,000 grant from the Alaska Industrial Development and Export Authority (AIDEA) to purchase and install a wind turbine. GVEA has spent an additional $31,000 in equipment and services in support of the project.

Wind turbine characteristics

A Bergey Excel 10-kilowatt (KW) wind turbine was installed on an existing microwave tower at GVEA's Healy Repeater site. A specially built adapter was used to support the wind turbine. The adapter raises the turbine twelve feet above the top of the tower so that clearance from the existing tower to the blades is maintained as the turbine rotates to face the wind.

The variable frequency three-phase power generated by the wind turbine is converted to single phase 120-volt, 60-hertz power via electronics, and fed through a meter and 100-amp breaker. Then a distribution transformer steps the voltage up to 14kV and feeds it into GVEA's distribution system. The electronics package includes safety features that protect the system from electrical faults and prevent the wind turbine from energizing the distribution transformer during an outage.

The Bergey wind turbine weighs 1,020 pounds and has a blade diameter of 23 feet. It begins producing power at wind speeds of 8 miles per hour (MPH), and increases its output up to 28 mph. Once the wind speeds reach 35 mph, the blades begin to furl and output decreases. This is a built-in safety measure to protect the blades from spinning too fast and becoming damaged.

Turbine installation

Before installing the turbine, GVEA hired PMCT to move antennas, located at the top of the tower, to the middle of the tower ($854). Griffard Steel inspected and repaired the tower to ensure that it was in good condition ($3000). GVEA hired Microflect (the manufacturer of the tower) to analyze the additional loading and help design the adapter ($2800). Griffard Steel was hired to mount the adapter and wind turbine on the tower ($6350). GVEA's electricians installed the inverter, meter, and SCADA interface in the communications building at the base of the tower. A GVEA lineman connected the equipment to the existing secondary conductor for the building service. GVEA engineering produced design drawings for the electrical work and a contract with AKW&S. Engineering also coordinated the efforts of PMCT, GVEA crews, Microflect, and Griffard Steel. GVEA, AKW&S, and AIDEA have spent a total of approximately $51,000 on this project.

Data Collection

GVEA's SCADA system automatically recorded the power production, and engineering downloaded the information approximately twice a month. AKW&S collected wind speed and temperature data at the site and sent it to GVEA.

Output

Total energy production was 25,358 kWh. The system availability was 74.9% from the time it was energized until the time power conversion electronics failed in October of 2000. The total energy produced for the same period was 13.8% of rated capacity. For comparison, production from commercial wind farms is typically 25%-35% of rated capacity.

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