The Hawaiian Electric Cos. have released an updated near-term action plan that suggests the state can meet a 100% renewable target sooner than 2045.
Hawaiian Electric Co. Inc., Maui Electric Co. Ltd. and Hawaii Electric Light Co. Inc., referred to as the HECO companies, said increased use of renewable energy and demand response between 2017 and 2021 can position the state to reach the 100% renewable portfolio standard, or RPS, by 2040. In aggregate, the plan estimates that the state needs 326 MW of rooftop solar, 31 MW of feed-in tariff solar projects, roughly 115 MW of demand response, 360 MW of grid-scale photovoltaic solar and 157 MW of grid-scale wind capacity.
The plan suggests that a mix of solar, wind, battery storage and biofuels can provide the island of Molokai with 100% renewables by 2020, according to a Form 8-K filed Dec. 27.
Much of the estimated new build — 255 MW of distributed solar, 352 MW grid-scale solar and 64 MW of grid-scale wind — would be built on Oahu. Maui would also see a large amount of new build, including 38.4 MW of distributed generation solar, 62 MW of grid-scale wind, 6.7 MW of grid-scale solar, and 14.7 MW of demand resources, according to the plan.
The latest Power Supply Improvement Plan, filed with the state Public Utilities Commission on Dec. 23, updated modeling assumptions from a version of the plan filed in April. Seven planning principles were used by HECO to define its pathway for each island. The top three principles include prioritizing renewable energy as the first energy option, requiring that energy transformation include everyone and ensuring that the planning decisions today do not crowd out technological breakthroughs in the future. Under the principles, HECO also designed the plan to address grid modernization and climate change. (Hawaii PUC docket 2014-0183)
The plan calls for modernizing the state's electric grid to help integrate resources such as energy storage and renewable energy. How electric rates are designed will need adjusting to align with a future of more aggressive use of distributed generation, HECO said. For renewable projects built on military sites, the utility is also investigating how to reduce the customer bill impacts of integrating these renewable projects. The plan recognizes that the costs of modernizing the electric grid, the price of oil and the reduced use of coal and fossil fuels will move customer bills higher in the near term, but said that the plan's focus on pursuing low-cost renewable generation will, in the long term, leave customer bills flat or slightly lower.
Electrifying transportation will influence the sizing of customer-owned generation and energy storage projects and will also increase opportunities for demand response resources, the plan says.
In developing the plan, HECO had modeled various scenarios including the use of liquified natural gas, or LNG, and building the Kahe combined cycle project, but the latest plan leaves those resources out over the next five years.
"While LNG remains a potential lower-cost bridge fuel to be evaluated, the companies' priority is to continue replacing fossil fuel generation with renewables over the next five years as federal tax incentives for renewables begin to phase out," HECO said.
Similarly, an inter-island cable to reduce the need of building new capacity was not included in the near-term plan, but HECO said it would continue to evaluate the costs and benefits of inter-island transmission, according to the Form 8-K.
Over the upcoming months, HECO will be using Google Inc.'s Project Sunroof and Mapdwell's Solar System, developed by the Massachusetts Institute of Technology, to learn about the potential for rooftop solar in Hawaii, according to the plan.
The HECO companies are subsidiaries of Hawaiian Electric Industries Inc.