How Will Hawaiian Electric Achieve 100% Renewable Supply?

Hawaiian Electric has filed plans charting a 30-year course towards 100% renewable energy in Hawaii.
Published: Wed 06 Apr 2016

Just about this time last year Hawaii became the first state in the United States to make a commitment to achieve 100% renewable energy supply with a 2045 target date. [Engerati-Hawaii Looks To 100% Renewables]

The question is, moving up from a level of approximately 23% in 2015, how to achieve that goal? Now Hawaiian Electric Companies, which includes Hawaiian Electric, Maui Electric and Hawaii Electric Light, has submitted plans outlining the next steps to the Public Utilities Commission for approval.

Together these companies provide electricity for 95% of the state‘s residents on the islands of Oahu, Maui, Molokai, Lanai and Hawaii Island. Anticipated milestones include achieving 100% renewable energy on Molokai and Lanai by 2030 and on Maui and Hawaii Island by 2040.

Smart grids in Hawaii

A key foundational action for the company towards the 100% renewable goal is implementing a smart grid with a modern wireless network, smart meters and other enhanced technologies to modernize the existing power grid, increase customer options and improve the integration of distributed energy resources.

The smart grid programme was initiated in 2014 with grid upgrades for 5,000 customers that also demonstrated the technologies. In the next phase it is proposed to install smart grid technology for more than 455,000 customers on Oahu, Hawaii Island and in Maui County. Once approved this could start in 2017 on Oahu and in 2018 on the other two islands.

In addition, customers will be provided with a web portal and a project is already under way with Blue Planet to test the influence of detailed energy information on consumer behaviour.

More renewable generation

On the generation front it is proposed to put out RFPs for a variety of renewable energy projects with a combined capacity of more than 350MW to be developed on the islands by 2022. Alongside this. the continued growth of private rooftop solar will be supported through new programmes, while community-based projects will be implemented for consumers who can’t or choose not to instal rooftop solar. [Engerati-50 Home Community Solar Project To Pilot In Hawaii]

It is also proposed as an interim measure starting as soon as 2021 and ending by 2040 to import and use liquefied natural gas (LNG) for electricity generation. With its lower price volatility than oil and cleaner emission footprint, LNG is believed to provide the most cost-efficient generation option during the 100% transition. A new combined cycle unit would replace older generating units at the Kahe Generating Station and LNG is proposed for the Maalaea power plant on Maui and the Keahole and Hamakua Energy Partners plants on Hawaii Island.

Other proposed plant retirements include two generators at Waiau Power Plant and the four generators that make up the Kahului Power Plant on Maui, as well as a steam generator in Puna on Hawaii Island.

Other proposals in the plan include:

• Implementing a demand response management system to provide customers with more options and to increase integration of rooftop solar

• Installing circuit level improvements on all islands (upgraded conductors, voltage regulators, transformer replacements, reconfiguring circuits, distributed energy storage, advanced inverters)

• Pursuing both residential and utility-scale energy storage options

• Modifying and improving existing generation (lower operating levels, ramp improvements) to help facilitate the integration of renewables

•  Microgrids at military facilities to support resiliency and energy security.

A 100% renewable vision

While the full plan doesn’t appear to have been publicly released nor other next step details such as costings, beyond that inflation-adjusted electric rates are projected to remain stable and relatively flat overall, Alan Oshima, president and CEO of Hawaiian Electric Company, is confident that the 100% renewable future can be achieved.

“We want to work with parties from all segments of our community – government, business, community, and environmental groups – to refine the plans for Hawaii’s energy future,” he comments. “And while the vision remains the same, a 30-year plan to get there will naturally change given the rapid development of new technology, changing policy and costs, and other factors.”

According to the company press release more than 130 different scenarios were modelled in the planning. One possible scenario for a 100% mix for Oahu, Maui County and Hawaii Island in 2045 is as follows:

1,215MW private rooftop solar energy

36MW feed-in-tariff solar energy

872MW utility-scale solar energy

529MW onshore wind energy

800MW offshore wind energy

21MW hydropower

118MW geothermal energy.

However further studies are required on for example inter-island cabling for offshore wind, while technology advancements, pricing and other variables also will impact the mix 30 years hence.