There’s a growing sense of urgency as the slated retirement of AES Hawaii, Oahu’s coal-fired plant at Campbell Industrial Park, grows near.
Hawaiian Electric plans to retire AES Hawaii, a 180- megawatt coal-powered plant that provides about 20% of Oahu’s electrical needs, in September 2022, when the state’s ban on the use of coal to generate energy goes into effect.
The question is what will replace it during the transition: renewables or fossil fuels.
An ongoing debate over the transition plan, and what it involves, are on the agenda at a state Public Utilities Commission status conference today.
At least three major solar-plus-battery projects, including two that just broke ground last week, could have potentially offset the loss from coal. But the solar projects have been delayed by a year, and won’t be online until after the coal plant’s retirement.
Without the necessary increase in solar power generation, Hawaiian Electric will likely have to turn to oil power generation to compensate for the loss of coal power for at least a few months, which does not sit well with the commission.
“Your plan to me amounts to a shift from one fossil fuel to another,” PUC Chairman James Griffin said during a mid-March conference on the coal plant closure. “We’re going from cigarettes to crack.”
San Francisco-based Clearway is building the solar- plus-battery projects in Mililani and Waiawa, offering 75 megawatts of power combined, along with 300 megawatt-hours of storage that are slated to come online in November and December 2022.
They will help provide electricity once coal is gone.
The discussion now centers on how Clearway might expedite their projects — and move them up by three months — ahead of the coal plant’s retirement.
The solar projects were delayed by a year or more, largely due to interconnection issues — a highly intensive process requiring numerous studies that allow renewable systems to safely connect to Hawaiian Electric’s grid.
Clearway, which is focused on obtaining financing, said it would need to work with suppliers, contractors and lenders to determine whether this acceleration is possible, along with associated costs and risks.
The PUC said of numerous projects solicited through two rounds of bidding — which began as early as 2018 — only one solar-plus-battery project, capable of generating 12.5 MW of power, is expected to be done before AES Hawaii’s retirement.
Also, the commission expressed concerns that Hawaiian Electric is banking too much on the Kapolei Energy Storage project, a giant lithium-ion battery that is expected to provide a reliable source of fixed power when the coal plant retires and which is still pending PUC approval.
Unless more renewable projects come online sooner, the primacy source of power for the stand-alone battery project would come from fossil fuels — a move that commissioners are not pleased with.
Griffin estimated costs of battery storage plus oil at market prices could push costs higher, to possibly 25 to 30 cents per kilowatt- hour.
In comparison, some of the grid-scale, solar-plus- battery projects, including those delayed, when first announced in 2019, had contracts to sell power at about 10 cents per kilowatt-hour.
Hawaiian Electric said over its 20-year life, Kapolei Energy Storage is actually estimated to lower the average residential customer’s bill by about 28 cents per month.
Also, for most of the 20 years, the utility said, energy stored in the system will come from solar and wind sources, not fossil fuels.
The utility defended its performance bringing renewable energy projects online, saying that many delays were not solely its fault and that some were on the developers’ side in failing to meet modeling requirements on time or due to project design changes.
There was also a pandemic, which challenged everyone.
A new task force to be chaired by Scott Glenn of the Hawaii State Energy Office has been set up to coordinate all parties involved to get renewable-energy projects online ahead of the coal plant’s retirement.
The PUC today will also discuss the transition plan on Maui, which faces a similar conundrum. On Maui a number of renewable projects are delayed by two years, with the oil-fired Kahului Power Plant set to retire in 2024.
PUC STATUS CONFERENCE HEARING
>> What: Clearway project timelines, Kahului transition plan
>> When: 1-3 p.m. today
>> Livestream link: puc.hawaii.gov
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PROJECTED ENERGY MIX FOR OAHU
Set to retire
>> AES Hawaii: 180-MW coal plant, set to close September 2022
Solar-plus-battery projects delayed beyond September 2022
>> Mililani I Solar: 39 MW plus 156 MWh storage (expected November 2022)*
>> Waiawa Solar: 36 MW plus 144 MWh storage (expected December 2022)
>> Hoohana Solar: 52 MW, 208 MWh storage (expected August 2023)
Solar-plus-battery project coming online September 2022
>> AES Solar West Oahu: 12.5 MW plus 50 MWh storage
Pending approval
>> Kapolei Energy Storage: 185 MW plus 565 MWh storage
* Guaranteed commercial operations date as of April 12
Source: Public Utilities Commission