Cheaper electricity. Quieter streets. Less pollution.

These are envisioned benefits for Hawaii if the state’s largest utility can pave the way for most personal vehicles in the state to run on electricity within 27 years, up from fewer than 1 percent today.

Hawaiian Electric Co. filed a report it calls a “road map” with the state Public Utilities Commission last week to reach that 2045 goal.

“This road map lays out the steps for meeting the changing needs of our customers and communities and adapting to the new technologies we know are coming,” Brennon Morioka, Hawaiian Electric manager for electrification of transportation, said in a statement. “This is a global movement that is transforming the way that individuals, families and businesses use vehicles and we have to be ready.”

It won’t be easy.

The report says necessary steps will include helping lower electric vehicle costs, adding thousands of public charging stations, making daytime vehicle charging optimal and helping operators of commercial fleets and heavy equipment such as buses, delivery vans, rental cars and construction vehicles convert to electric.

Success, however, could produce big benefits — even for those who don’t own an electric vehicle.

Hawaiian Electric said charging so many more vehicles would make room for nearly 200,000 additional home rooftop solar systems as well as many utility-scale renewable energy production plants that take Hawaii closer to a goal of 100 percent energy generation from renewable sources.

To give a sense of the electricity demand generated by vehicles, the utility said charging one bus consumes about as much energy as 14 homes.

With such a dramatic boost in electricity demand and supply, fixed costs for grid infrastructure and other things become cheaper because they get spread over more users, Hawaiian Electric said.

The utility said the size of its envisioned shift from gas-powered to electric-­powered vehicles could save its customers $60 million over 27 years regardless of whether they own an electric vehicle. On top of that, reduced transportation expenses for electric vehicles, which avoid higher costs of gas and maintenance compared with internal-­combustion engine vehicles, would add an additional $120 million in savings.

If it were convenient for electric vehicle owners to charge during the day when solar panels produce low-cost electricity, total benefits to the state could top $311 million and alleviate a need to upgrade grids to support charging during evening peak electricity use. The report imagined that public charging stations in 2045 could send special discount pricing alerts to drivers when there is excess solar energy production.

Hawaiian Electric said that even today with relatively low gas prices, charging an electric vehicle at the typical residential rate can cost about 35 percent less than fueling a gas-­powered car of similar size.

On the flip side, electric vehicles cost more, even with a federal tax credit up to $7,500. The road map predicts that gas-powered and electric-powered vehicles will reach price parity by 2025.

HECO said it will have to work with automakers, dealerships and advocates to lower electric vehicles’ prices and educate consumers about options and benefits. The road map also said new-car dealers have more incentive to sell traditional vehicles because they generate more revenue from parts and maintenance.

Dave Rolf, executive director of the Hawaii Automobile Dealers Association, said 31 of the state’s 70 new-car dealerships have an electric car in their lineup.

At the First Hawaiian International Auto Show, Friday-Sunday at the Hawai‘i Convention Center, rides in electric vehicles are planned, and display models will include a variety of electric vehicles including a sedan-­SUV cross from Chinese car maker BYD that is popular with taxi companies. However, the association projects that electric vehicle sales in Hawaii in 2045 will represent only one-third of all new cars and trucks.

Rolf said the utility’s 159-page road map is impressive, but he also said that “it seems to call for traveling over bridges that aren’t in place yet.”

Along with electric vehicles’ prices, another challenge to realizing the 2045 vision is expanding a reliable network of public charging stations.

The road map cited an estimate by the U.S. Department of Energy that 8 percent of Hawaii public charging ports were out of order as of April 2017 and that this figure is probably low.

There are 524 charging ports statewide, including 69 that will fully charge a vehicle in about 30 minutes, the road map said. As of January there were 6,748 electric vehicles for personal use, which among states is second most per capita after California.

“Insufficient availability of suitable and reliable charging infrastructure is a significant barrier,” the report said, noting that 38 percent of residents live in condominiums or apartment buildings where it can be prohibitively expensive to provide charging for electric vehicles.

A lack of charging stations where people work is another issue.

Ford Motor Co. said in written comments on the report that workplace charging needs to be prioritized.

Local nonprofit Blue Planet Foundation said in written comments that the utility committing to expand charging infrastructure is key to helping grow electric vehicle use, which benefits the environment and residents.

“The (report) is an important step toward realizing a cleaner, brighter future for Hawaii,” wrote Melissa Miyashiro, the foundation’s chief of staff.

Hawaiian Electric said steps in the report for overcoming challenges will help stakeholders work more efficiently toward realizing the 2045 vision.

“The timing and precise route may change, but our destination and determination to reach it are clear,” HECO’s Morioka said.