A bill (HB 635) introduced to Hawaii’s 29th State Legislature could lead to the installation of a pumped-storage hydroelectricity project at the Nu’uanu Reservoir on the island of Oahu.
The legislation – sponsored by State Representative Ryan Yamane (D-District 37) – would allocate up to $6.4 million in special purpose revenue bonds to the Honolulu Board of Water Supply and Hawaiian Electric (HECO) for the upgrade of Nu-uanu Reservoir #4 to meet state dam safety standards.
The system would work by using cheap solar energy during the day to pump water uphill to a reservoir, and then releases that water at night, running down a pipe, turning a turbine and making electricity, according to a report in Pacific Business News.
Indeed, a story that ran on PBN last week noted that an expert had said that there could be between 100 MW and 200 MW of pumped storage hydro potential on Oahu , just looking at existing reservoirs. Those with the most potential for pumped hydro storage include Lake Wilson in Wahiawa and the Upper Nu-uanu Reservoir.
Jeff Mikulina, executive director for the Honolulu-based renewable energy nonprofit Blue Planet Foundation, has told PBN that hydro storage is an existing, commercially operating and cost-effective energy storage technology being used in many places.
If approved, the bill is set to become effective on July 1.