A major spending bill heading to the U.S. Senate could reduce federal support for electric vehicles.
The measure, proposed by House Republicans, would sunset subsidies and set a new fee for EV purchases.
The House Reconciliation Bill, known formally as the One Big Beautiful Bill Act, rolls back many Biden-era climate and energy programs and proposes cuts to government benefits like Medicaid and SNAP.
A $7,500 incentive to buy new EVs would end in 2026, and another $4,000 tax credit for the purchase of used EVs would end this year.
If the Senate agrees to the bill's current language, EV owners would also have to pay $250 on top of their annual registration.
That fee is intended to make up for lost gas tax revenue. Drivers pay fixed federal and state gas taxes at the pump, which support road maintenance and other transportation projects.
Gas tax revenue has been shrinking as the number of EVs rises. Some states, including Hawaiʻi, have been looking at ways to recoup lost funds.
A fee on EVs can be applied fairly, said climate analyst Jeff Mikulina. But he believes the proposed fee in the federal measure is excessive.
"This bill takes a very unfair approach and throws out this random number of $250, which is nowhere near what the typical gas tax collects at the federal level for other vehicles," he said.
Mikulina also pointed out that gas cars have long-term costs.
"Gasoline vehicles have a disproportionate impact on our environment. We pay for it in another way, and that's through climate damages."
Starting July 1, Hawaiʻi EV owners will be charged a state fee. They can choose between a mileage fee of $8 per 1,000 miles or an annual $50 fee.
