Public Utilities Commission approval helps Kauai utility close in on renewable goals

Kauai is expected to approach 70 percent renewable generation by the end of 2019 after receiving approval this week from the state Public Utilities Commission for development of a 19.3-megawatt solar facility along with a 70 megawatt-hour battery energy storage system.

The facility at Pacific Missile Range Facility at Barking Sands will be built by AES Distributed Energy on land leased from the Department of Defense. It will displace 2.8 million gallons of diesel annually and produce enough power to energize 6,000 homes.

It also will be one of the Kauai Island Utility Cooperative’s lowest-cost power sources. KIUC has signed a 25-year power purchase agreement with AES at a price of 10.85 cents per kilowatt-hour.

“KIUC’s board of directors set an aggressive goal of reaching 70 percent renewable by 2030,” KIUC President and CEO David Bissell said Friday in a statement. “Once this project is complete, we will be very close to that mark a decade early.”

The AES project at Pacific Missile Range Facility is the third battery storage project undertaken by KIUC since 2015. In early 2017 KIUC and Tesla opened the world’s first utility-scale solar-plus-storage facility in Kapaia. The Tesla plant is now storing up to 52 MWh of energy on a daily basis, which is primarily dispatched to the grid during the evening peak demand period.

In February 2018 AES broke ground on KIUC’s second solar-plus-battery project in Lawai. The Lawai facility is slated to be operational by the end of this year and consist of a 28 MW solar photovoltaic system and a 20 MW five-hour duration energy storage system.

“These storage projects are moving us rapidly closer to our renewable goals,” Bissell said. “By the end of 2019, KIUC will be able to supply roughly 65 percent of Kauai’s nighttime peak load with stored solar generated energy. To be able to accomplish this in a cost- effective manner was just a dream a few years ago. The partnerships between KIUC’s engineers and those of some of the best renewable energy companies in the world is making the impossible a reality.”

Another KIUC renewable project in development will use pumped storage hydro technology to create 25 MW of energy on the west side of Kauai. The Puu Opae project involves the rehabilitation of three reservoirs and other agricultural infrastructure on state land in Waimea. The project, once completed, will provide a significant renewable power source for KIUC and also pave the way for the state Department of Hawaiian Home Lands to place homestead property into productive agricultural use.

“If all goes well with the two AES projects and Puu Opae, we estimate we will be approaching 90 percent renewable by 2023,” Bissell said.