Hawaiian Electric is weighing whether to push back the retirement of its fossil fuel-reliant Kahului Power Plant as it works to get spare parts for four engines at another key facility.
Earlier this month, the company received the “unanticipated news” that the supplier of the spare parts for four units at the Maalaea Power Plant may not be able to provide them, Hawaiian Electric told the state Public Utilities Commission in a letter on Monday.
The four large diesel engines at the largest power plant in Maui County provide up to 50 megawatts of the island’s total firm generating capacity of 248 MW, according to Hawaiian Electric spokesperson Shayna Decker.
“While we continue to explore ways to extend the operation of the four units and work to bring on more renewable energy resources, at the same time, it is prudent for us to assess if postponing the retirement of the generating units at the Kahului Power Plant is needed,” Decker said in an email Thursday. “We are looking at every option to ensure we continue to have a sufficient supply of power to meet the energy needs of our Maui customers.”
Hawaiian Electric has been planning to retire the Kahului plant in 2024 as the state moves toward its goal of 100 percent renewable energy by 2045. The plant was shut down in 2014 but reactivated in 2016 to meet a growing demand for power after the closure of Hawaiian Commercial & Sugar Co., which once supplied some energy to island residents.
In December, the PUC approved Hawaiian Electric’s plans to make equipment modifications to two of the four retiring oil-firing generating units at the Kahului Power Plant, Decker said. Two units will be used to control voltage and maintain inertia on the system without the use of fuel oil, while the other two will be permanently shut down and no longer able to generate electricity.
Put into service in 1948, the Kahului plant generates 36 MW that will need to be replaced before it’s taken offline, making the remaining facilities and upcoming clean energy projects crucial to Hawaiian Electric’s plans moving forward.
Given supply chain issues, Hawaiian Electric told the PUC that it’s been reaching out to certain suppliers and trying to acquire spare parts and materials ahead of schedule whenever it can.
In one case, Hawaiian Electric contacted Mitsubishi Heavy Industries Engine & Turbochargers, which supplies parts for the four Maalaea units. The Chicago office of the company’s American subsidiary informed Hawaiian Electric that “MHIET hasn’t had the specific timeline to the end of parts supply so far.”
“We surely would like to keep the parts supply to MECO for the engines as much as we can,” the company said in a March 2 letter. “However, the engines have manufactured for more than about 40 years ago, some engine-related parts might no longer be available for supply due to the business closing at our suppliers and if there is no alternative way to produce parts anymore.”
The response surprised Hawaiian Electric Senior Vice President aChief Operations Officer Jim Alberts told the PUC in a letter on Monday. He said “the fact that the response from MHIET was not an unequivocal commitment to continue to provide parts is enough of a concern to warrant the company to revisit Maui’s capacity planning and energy reserve margin.”
Hawaiian Electric does have enough spare parts on hand for “one additional 12,000 run-hour major overhaul for each engine.” With overhauls planned over the next two years and current operations showing that it takes about 30 months to reach 12,000 run-hours, the engines will be at or near the end of their life-span by 2025 or 2026, according to the letter.
Hawaiian Electric is working to get enough spare parts to extend the units’ lives, but few engines of this type still exist, and the critical parts needed are unique to the Mitsubishi version.
“However, the uncertain circumstances must be considered, and it is no longer prudent to safely assume continued operation of these units past the dates shown above in capacity planning for Maui,” Alberts said. “As one example, it may not be prudent to retire Kahului Units 1 thru 4 prior to sufficient capacity being in service to replace the 36 MW they represent as well as the 50 MW supplied by M10 thru M13 (at Maalaea). That said, to comply with Regional Haze rules, it is anticipated that the Kahului Units may need to be retired by the end of 2027.”
Alberts outlined an action plan that includes exploring ways to extend the lives of the Maalaea units, working with renewable energy developers to make sure their projects are installed no later than 2024, starting the process for permits for the Waena battery storage project and seeking approval to establish a Battery Bonus program for Maui that would offer cash incentives and bill credits for adding a battery to a rooftop solar system.
“We’ve been working closely with developers to ensure these renewable energy projects continue to move forward,” Decker said. “Several renewable energy developers have informed us that their renewable energy projects could be delayed or otherwise impacted by the global supply chain crisis. They’ve cited delays in production of battery energy storage system and racking equipment, delays in shipping, and cost increases for both materials and labor. We do not intend to cease operation of the Kahului plant until sufficient resources to replace it are in place and operational.”
When asked what would happen if the Maalaea units were to die, Decker said that “since we regularly maintain our generating units, were proactive in our efforts to increase our stock of supply parts and are carrying out the steps in our Action Plan, we anticipate the units to be able to continue to reliably supply power.”
“Impacts are not confirmed at this point because it would depend on what new, replacement generation resources will be online and what the island’s energy demands will be as we move forward,” she said.
* Colleen Uechi can be reached at [email protected]