Cordova has a long history of resiliency in the face of challenges, but its entire way of life was threatened in 1989 when the Exxon Valdez oil spill caused severe ecological and economic damage to the town and throughout the region. Due to its remote location, disaster response efforts did not fully meet the needs of the community and Cordova ultimately had to rebuild its economic base and infrastructure. This was a painful lesson.
As part of the recovery from the oil spill, Cordova Electric Cooperative (CEC) swiftly accelerated its move away from using diesel generators and diesel fuel, which had to be imported by ship. Relying on diesel was both costly and environmentally hazardous. The new direction toward energy autonomy focused on establishing a hybrid microgrid which would enable the adoption of renewable power from a variety of sources, including two new hydroelectric projects.
One of the key components of the microgrid plan was a battery energy storage system (BESS) that would help CEC regulate the electrical system and maximize the use of locally produced hydroelectric power. The BESS system came online in 2019, and with the BESS-supported microgrid in place, CEC has been able to reduce its dependence on diesel and move closer to its goals for sustainability, reliability and long-term management of the town’s electrical system.
In addition to environmental concerns, cost is also a major factor in delivering electricity to the town, and CEC prefers to run on hydropower as much as possible due to the economic advantages. For CEC, hydropower averages around $0.06/kWh, while diesel generation costs can be as much as ten times higher, depending on highly variable fuel prices. Hydropower alone meets as much as 78% of annual demand, but one of the key goals of the microgrid project has been to recover the hydropower lost during transition periods.
“While these hydroelectric projects provide almost all of our power in the summer, and a good portion of our power in the winter, they're just run-of-the river projects,” continued Koplin. “They don't store any energy at all. There's no dam to store the water, so we needed a way to balance our system loads.”