Hawaiian Electric said last week it submitted contracts for seven “solar-plus-storage” projects to the Public Utilities Commission for review.
The projects — three on Oahu, two on Maui and two on Hawaii island — are expected to add about 262 megawatts of solar energy with 1,048 megawatt-hours of storage. The projects are the largest and lowest-cost portfolio of renewable energy resources to be assembled in Hawaii, according to Hawaiian Electric.
Solar-plus-storage projects include solar photovoltaic arrays that generate power during the day, and storage systems could provide another four hours of power when the sun is not shining.
“We believe strongly that the renewable energy transformation should benefit everyone and these seven projects will help stabilize customer costs while reducing our reliance on imported fossil fuel and cutting greenhouse gas emissions,” said Shelee Kimura, Hawaiian Electric senior vice president of business development and strategic planning, in a news release.
A mix of solar companies have agreed to the power purchase agreements with Hawaiian Electric, including AES Distributed Energy of Boulder, Colo.; Innergex Renewable Energy of Canada; 174 Power Global Corp. of Irvine, Calif., an affiliate of Hanwha Group of South Korea; and Clearway Energy Group of San Francisco.
While 174 Power Global is planning to build Hoohana, a 52-megawatt solar-plus-storage project on Oahu, Clearway has agreed to build two solar-plus-storage projects: Mililani I Solar at Mililani Agricultural Park and Waiawa Solar Power in Waiawa.
Hawaiian Electric said the prices for six of the seven projects are the lowest, to date, for renewable electricity in the state, and that this flexibility enables the utility to dispatch energy from each facility to meet the needs of the grid.
Proposed prices for the sale of power to Hawaiian Electric range from 8 to 12 cents per kilowatt-hour.
Those rates are significantly lower than the 18 cents per kilowatt-hour power purchase agreement that the Public Utilities Commission approved last year for a solar-plus-storage system on Molokai.
The prices, if approved by regulators, are charged to customers with no markup or profit to the utility, according to Hawaiian Electric, and are significantly lower than the current cost of fossil fuel generation, which is about 15 cents per kilowatt-hour.
Collectively, Hawaiian Electric, Maui Electric and Hawaii Electric Light already have more than 500 megawatts of renewable energy under contract and nearly 80,000 private solar PV rooftop systems in operation.
The seven projects could potentially reduce up to 100 million gallons of oil imported annually to the state to generate electricity.
Hawaiian Electric put out a bid for the solar-plus-storage projects in February. The seven were selected from about 20 proposals and could be in service by 2022 if approved, according to Hawaiian Electric spokesman Peter Rosegg. Another request for proposals will likely go out this year, with these prices as a benchmark.
The contract for a 12.5-megawatt solar PV array in West Oahu, which includes a 50-megawatt-hour storage system, is expected to be submitted to the PUC in coming weeks.
Separately, the Kauai Island Utility Cooperative held a blessing Tuesday for the Lawai‘i Solar and Energy Storage Project on the Garden Island’s south shore.
Owned and operated by AES Distributed Energy, which is also planning a project on Hawaii island and Maui, the 28-megawatt solar PV facility and 100-megawatt-hour energy storage system sits on former sugar cane land owned by Alexander & Baldwin. The system can supply the grid with peak power output for up to five hours while simultaneously charging the batteries.
KIUC will purchase the power from AES at 11 cents per kilowatt-hour over 25 years.
The system is expected to supply as much as 40 percent of Kauai’s evening power, offsetting the use of 3.7 million gallons of diesel each year. With the new system, KIUC’s renewable portfolio grew to more than 50 percent compared with 8 percent in 2010.
Seven proposed solar-plus-storage projects for Hawaii
Project name, island, developer, size, cost per kilowatt-hour:
>> Waikoloa Solar, Hawaii island, AES, 30 megawatts, 8 cents
>> Hale Kuawehi, Hawaii island, Innergex, 30 megawatts, 9 cents
>> Kuihelani Solar, Maui, AES, 60 megawatts, 8 cents
>> Paeahu Solar, Maui, Innergex, 15 megawatts, 12 cents
>> Hoohana, Oahu, 174 Power Global, 52 megawatts, 10 cents
>> Mililani I Solar, Oahu, Clearway, 39 megawatts, 9 cents
>> Waiawa Solar, Oahu, Clearway, 36 megawatts, 10 cents