The Department of the Army will in the Feb. 5 Federal Register announce the availability of the Record of Decision (ROD) to lease land and grant easements on Schofield Barracks and Wheeler Army Airfield to Hawaiian Electric for the construction, ownership, operation, and maintenance of the 50-MW, biofuel-capable Schofield Generating Station.
The ROD also covers associated power poles, high-tension power lines, and related equipment and facilities. The action was the preferred alternative identified in the final Environmental Impact Statement (EIS) for the Schofield Generating Station Project (SGSP). The ROD identifies the potential environmental and socioeconomic impacts associated with the SGSP, none of which were determined to be significant adverse effects.
The selected action will provide improved energy security to the Army and citizens of Oahu, support renewable energy goals, and improve future electrical generation capabilities on Oahu by providing a new secure, firm, dispatchable, flexible, and renewable energy generation to the grid on Oahu. The Army and Hawaiian Electric will implement numerous best management practices to avoid or minimize adverse environmental effects.
The Army would lease 8.13 acres of land and grant a 2.5-acre interconnection easement to Hawaiian Electric. The selected action best meets the Army’s needs to provide improved energy security to the U.S. Army Garrison-Hawaii at Schofield Barracks, Wheeler Army Airfield, and Field Station Kunia and to provide new secure, firm, flexible, and renewable energy generation to the grid on Oahu. The selected action will also assist the Army in supporting renewable energy-related laws and Executive Orders and meeting its renewable energy goals; assist Hawaiian Electric in meeting the Hawaii Renewable Portfolio Standard goals; and improve future electrical generation on Oahu.
The electricity produced by the SGSP will ordinarily supply power to all Hawaiian Electric customers through the island-wide electrical grid. During outages that meet the criteria specified in the Operating Agreement between the Army and Hawaiian Electric, SGSP output would first be provided to Army facilities at Schofield Barracks, Wheeler Army Airfield, and Field Station Kunia up to their peak demand of 32 MW, to meet their missions, and would additionally support the grid up to the station’s full capacity. If there were a full island outage, the generating station could be used to restart other generating stations on the island.
The U.S. Army Garrison-Hawaii in October 2015 issued a final environmental impact statement finding little in the way of environmental consequences for this project. The final EIS was prepared with the help of parties like Hawaiian Electric and consultant Tetra Tech Inc.
Hawaiian Electric has several objectives that would be met with this project, including:
- Provide 50 MW of new, easily dispatchable capacity to support the Oahu grid, which will contribute to Hawaiian Electric’s ability to deactivate older, less efficient generating units;
- Add a fleet of modern, efficient generating units that can use multiple fuels, including biofuel, and facilitate integration of additional renewable resources that will contribute to meeting or exceeding the state Renewable Portfolio Standard (RPS);
- Provide a quick-starting, high ramp rate facility to help maintain grid stability and support the increasing penetration of variable and distributed sources of power generation, such as wind and solar, on the Hawaiian Electric grid;
- Have a power generation facility at elevation and away from coastlines, which contributes to continuity of electrical power in the event of natural disaster;
- Provide reliable backup power to Wheeler Army Airfield to enhance military, National Guard, and civilian disaster response capabilities; and
- Locate a generation facility on a military installation to contribute to energy security for Hawaiian Electric customers if there is a man-made threat.
The Schofield Generating Station would consist of six Wartsila 20V34DF (or similar) multi-fuel-capable, reciprocating internal combustion engine-generator sets and associated equipment. Each engine would be equipped with selective catalytic reduction (SCR) equipment containing catalysts to reduce nitrogen oxide (NOx) emissions, and an oxidation catalyst to reduce carbon monoxide (CO) emissions. The new facility would provide a total gross generation rating of 50 MW.
Auxiliary equipment would include inlet air filters, gas exhaust silencers and stacks, a closed-loop air cooled radiator array, generator step-up and auxiliary transformers, fuel and lubricating oil handling equipment and associated storage tanks, a water purification system, a urea mixing system to supply the SCR emissions control system, a switchyard, and a facility to receive and regasify liquefied natural gas (LNG).
The generator sets would be installed in a single engine hall. Each generator set would generate approximately 8.4 MW gross. Each of the six engine-generator sets is expected to have an overall annual availability (i.e., operability rate) of more than 95%, including scheduled and forced outages. Each engine is designed to start and be fully operational in 6 minutes or less. Each engine is to provide various ancillary services, such as ramp up, ramp down, spinning reserve, and voltage and frequency regulation, allowing these units to readily adapt to changing conditions that might arise with large amounts of as-available generation on the grid. The engines can operate at partial load, with a minimum load of 50%. Because each engine can operate independently, this gives the 50-MW plant a minimum load of approximately 4.2 MW.