Hawaii’s largest electrical utility has formalized a three-year plan to reduce future wildfire risks in a new report filed with state regulators.

Hawaiian Electric said its latest wildfire safety strategy is expected to cost $450 million to implement over three years through 2027 after $120 million spent on wildfire risk mitigation in 2024.

The company also said continued refinements could result in changes to the future scope of work and costs.

Hawaiian Electric’s 179-page report was filed Friday with the state Public Utilities Commission to comply with an order the PUC issued in September, and includes many detailed elements of a strategy that company officials shared with a panel of state senators in November.

Shelee Kimura, Hawaiian Electric president and CEO, said in a statement that the report builds upon a wildfire mitigation plan the company first created in 2019 and updated in the months after the Aug. 8, 2023, Maui wildfire that killed 102 people and destroyed most of Lahaina.

Kimura also said hundreds of stakeholders and partners — including county, state and federal agencies as well as elected officials, landowners, businesses, community organizations, customers, peer utilities and expert advisers — contributed to wildfire prevention efforts that include contributions to the company’s plan.

“Our 2025-2027 expanded wildfire safety strategy builds upon our past work and that of many others,” she said. “It is not just a technical roadmap, it is our shared and steadfast commitment to a safer, more resilient Hawaii. … Through collective action and thoughtful approaches, Hawaii can create a fire-safe environment for generations to come.”

Hawaiian Electric has about 471,000 customers and serves Oahu, Maui, Molokai, Lanai and Hawaii island.

The two most expensive pieces of work in the company’s wildfire safety plan are insulating bare electrical lines in high-risk areas at a cost of $60 million, and replacing fuses at a cost of $54 million.

Most of the utility’s existing fuses, which stop transmission of electricity in the event of a surge, can emit molten embers or sparks when they blow out to prevent system damage.

Other elements in the plan include putting about two miles of overhead power lines in Lahaina underground, installing stronger utility poles, enhancing equipment inspections, installing more weather stations and fire detection cameras, creating wider rights-of-way where the company can clear ground vegetation under power lines, and creating a wildfire-focused “watch office” for staff to monitor media reports, internal and external weather information and field reports.

Wildfire risk mitigation work completed by Hawaiian Electric in 2024 included establishing a Public Safety Power Shutoff program to deenergize electric lines when wind and relative humidity reach critical levels in certain areas, installing 2,124 stronger utility poles and upgrading 23 miles of older overhead power lines.

The company also said it set up 53 weather stations in wildfire-prone areas, installed 44 wildfire detection cameras and installed 3,588 sparkless fuses in 2024.

Hawaiian Electric said some of the cost to implement parts of its latest plan over the next three years are being funded by a $95 million federal grant for grid resilience sought in 2022 and received in 2024. The company also is pursuing additional federal funding but is paying for much of the cost to implement the plan.

The wildfire that struck Lahaina caused an estimated $5.5 billion in damage. A power line in the West Maui town that was damaged by high wind and reenergized after a visual inspection was found by an independent analysis to be a major contributing factor to the disaster, which has led to a pending $4 billion settlement for fire victims to be paid for mainly by the utility, the state and landowner Kamehameha Schools.

Hawaiian Electric’s share of the settlement totals $2 billion. The company, which previously contributed $75 million to a state fund for some victims, expects to pay out $1.92 billion in four equal annual installments of about $479 million. The first payment, expected by the end of this year, is covered by $558 million raised in September by the company’s parent selling new shares of stock.