Renewable Energy Can Power 3 Oʻahu Army Installations during Emergencies

A joint Hawaiian Electric-US Army exercise determined that during a major outage, the Schofield Generating Station on Oʻahu will be able to power up a utility-owned microgrid consisting of three U.S. Army installations in Central Oʻahu.

The inaugural test of the Schofield Generating Station’s microgrid capabilities affirmed that if power is lost at Schofield Barracks, Wheeler Army Airfield and/or Field Station Kunia – all critical lifelines during an emergency – the three installations can be isolated and powered with 100% renewable energy from the Schofield-based power plant.

During the 36-hour test in May, the Army shut off power to Schofield Barracks, Wheeler Army Airfield and Field Station Kunia on May 22. In less than an hour, Hawaiian Electric carved a microgrid out of its subtransmission system and restored power to the installations using Schofield Generating Station as the primary source of power, supplemented by the Army’s rooftop solar on the bases. Upon completion of the test, the Army again shut down the bases and Hawaiian Electric restored normal grid power. 

“Schofield Generating Station has been providing 100% renewable, reliable energy to our customers for several years now,” said Jack Shriver, Hawaiian Electric Director of Project Development. “This successful test adds ‘resilient’ to that list. Schofield Generating Station can keep critical infrastructure operating during a major outage, hastening recovery.” 

The ability to provide utility-grade microgrid power to these facilities during an emergency could significantly improve disaster response for all of Hawaiʻi. Wheeler Army Airfield also is home to Hawaiʻi Army National Guard helicopter units and the Civil Air Patrol, and during emergencies can be used as a Federal Emergency Management Agency air access and staging site.

Hawaiian Electric’s 50-megawatt Schofield Generating Station came online in 2018 and is on eight acres at Schofield Barracks that the Army is leasing to the company. During normal operations, the station sends power to the grid daily to benefit all customers.  

In return for the value of the 35-year lease for the Schofield Generating Station project, Hawaiian Electric guarantees the Army energy security – ensuring it will be able to restore power to the three installations within two hours if they were to lose power. The lease requires  Hawaiian Electric to conduct a one-time “full system test” of this capability to prove it can be  accomplished, which was completed in late May. 

“The Schofield Generating Station provides reliable access to energy during power disruptions and ensures Army readiness,” said Jack Surash, assistant secretary of the Army  for Installations, Energy and Environment.  

Keith Yamanaka, energy chief for the US Army Garrison-Hawaiʻi, said: “This collaboration developed, executed and operationalized energy resilience for the state of Hawaiʻi and the Army. This successful test of the Schofield Generating Station’s capabilities is the culmination of an unprecedented amount of coordination and joint efforts  between a utility company and a Garrison.”  

The exercise was the result of a collaborative effort between Hawaiian Electric, the US Army  Garrison-Hawaii, US Army Office of Energy Initiatives and US Army Corps of Engineers. 

The Schofield Generating Station is the only power plant on Oʻahu that is located inland, protected from the potential impact of storms, tsunami and rising sea level. Although capable of operating on biodiesel or diesel, since commissioning it has operated on 100% locally refined biodiesel.