Imagine a Hawaiʻi that has surpassed its goal of producing all of its electricity from renewable resources by 2045. In this vision, not only have homes and businesses gone carbon-free; so have ground and ocean transportation systems. 

Land-hungry wind and solar farms are gone, replaced by nuclear reactors fueled by salt, along with turbines driven by geothermal energy, biofuels and recycled iron powder. Ships run on ammonia, cars on next-generation batteries that don’t need rare earth minerals. Electricity is so abundant and cheap that electric train systems carry loads of passengers on all of the islands. 

This is one of the scenarios laid out in a study released this week by researchers from the University of Hawaiʻi and other institutions.

Titled “Assessment of the Scope of Tasks to Completely Phase out Fossil Fuels in Hawaiʻi,” the report offers a comprehensive view of what its authors say it will take for Hawaiʻi to reach its mandated goal.

The report’s conclusion: The current path of primarily replacing fossil fuel electricity generators with wind, solar and battery storage won’t work. 

“The status quo is not a scenario of safety or stasis,” the report says. “It is a scenario of structured vulnerability and creeping collapse.”

The purpose of the report, which includes nine potential models using various types of renewable energy, isn’t to recommend a particular model over others, said Peter Sternlicht, director of the non-profit Sustainable Energy Hawai‘i and co-author of the study. Instead, he said, it’s to show “a series of metrics within which you can craft your own model.”

“We have to rethink how we do things,” he said.

Current Policy Relies On Wind, Solar And Storage

The report is based on a previous study about phasing out fossil fuel globally conducted by Simon P. Michaux, an associate professor at Geological Survey of Finland. Michaux adapted the report for Hawaiʻi, serving as the lead investigator. The Geological Survey of Finland funded the Hawaiʻi report, Sternlicht said.

A team of co-authors from UH included Professor Nicole Lautze, founder and director of UH’s Groundwater and Geothermal Resources Center.

To reach its goal of 100% carbon-free electricity by 2045, Hawaiʻi’s current plan relies mainly on rooftop solar and big wind and solar farms built by third-party power producers, which sell the electricity at wholesale rates to Hawaiian Electric Co.

But that plan has hit strong headwinds.

Independent wind and solar developments have stalled recently as the 2023 Maui wildfires battered HECO’s finances. President Donald Trump’s avowed hostility to state renewable energy policies has added uncertainty. And the Hawaiʻi State Energy Office has been making the case to develop a liquefied natural gas terminal to power generators now using oil, raising concerns that the state is hedging its ability to meet the 2045 deadline.

Now comes the UH report with another twist: Forget wind and solar and batteries that require rare earth minerals, it advises. Instead Hawaiʻi needs two renewable resources perhaps more controversial than liquefied natural gas: geothermal and nuclear power.

“They’ve been selling the idea that we just put some wind and solar and everything will be OK,” Sternlicht said. “But it won’t.”

The report lays out nine possible scenarios, ranging from the status quo to the most “out there,” as Sternlicht acknowledges, which involves no wind and solar and electric trains on all islands. Others call for reducing energy consumption by 40% and there are various hybrid models.

All but the status quo rely on some geothermal and nuclear.

“We need to get rid of the fantasies,” Sternlicht said.

Lawmakers Have Called For Studies

Perhaps the real fantasy is assuming the public will easily buy the geothermal and nuclear options.

Proposing to use Hawaiʻi’s untapped geothermal resources, for instance, may be a non-starter because it has long been subject to controversy and litigation. Recent community meetings to extoll the benefits of geothermal to Big Island residents suggest many haven’t warmed to the idea. 

The Hawaiʻi Constitution, meanwhile, requires a two-thirds vote of the House and Senate to allow a nuclear fission plant to be constructed. 

Sternlicht acknowledges it will take a concerted effort to sway lawmakers, regulators and the public.

But already, there are signs that geothermal and nuclear energy have friends in high places.

Last session, Sen. Glenn Wakai, who chairs the Committee on Energy and Intergovernmental Affairs, introduced a bill calling for a study on the feasibility of using nuclear power in Hawaiʻi. The bill stalled, but lawmakers passed a separate resolution setting up a working group to study the issue. Another resolution calls for a study of geothermal.

In a text message, Wakai said the UH study validates the efforts of lawmakers.

“Hawaii isn’t looking into grandpa’s nuclear plant,” he said. “Technological advancements can pump out huge amounts of power with minimal waste.”

Developing the sort of “molten salt” reactors envisioned for Hawaiʻi at commercial scale will still take about five years, he said.

“The newly established nuclear working group,” he said, “is pacing policy with technology.”