Tesla to provide 13 MW of storage for dispatchable solar plant on Kaua’i

Written By: Stratton Report
February 16, 2016


On February 16, Kaua’i Island Utility Cooperative announced that SolarCity had selected Tesla Energy to supply the batteries for a first-of-its-kind solar array and energy storage system. KIUC has a 20-year PPA with SolarCity, buying power at 14.5 cents per kilowatt hour.

The proposed SolarCity/Tesla project is believed by the parties to be the first utility-scale system in the U.S. to provide dispatchable solar energy, meaning that the utility can count on electricity being available when it’s needed, even hours after the sun goes down at a cost only slightly more than that of KIUC’s two existing 12 megawatt solar arrays, whose output is available only during the day.

According to the utility, SolarCity made the selection after conducting a comprehensive competitive solicitation in the battery marketplace. The 52 MWh Tesla Powerpack lithium-ion battery storage system will feed up to 13 megawatts of electricity onto the grid to reduce the amount of conventional power generation needed to meet peak demand in the evening from 5 p.m. to 10 p.m.

By using the solar energy stored in the battery instead of diesel generators, KIUC will reduce its use of imported fossil fuels and also cut its greenhouse gas emissions.

The project has already received most of its required state and county approvals and is now awaiting approval by the Hawai’i Public Utilities Commission. KIUC and SolarCity have requested an accelerated timetable for review of the project so that construction work can begin by April with a goal of being in commercial operation by the end of 2016.

KIUC is a member-owned cooperative serving 33,000 customers on the island of Kaua’i.