A proposal to curb the use of heavy-duty pickup trucks on city streets could also impact EVs.

The District of Columbia could soon require owners of vehicles weighing more than 6,000 pounds to pay a $500 annual registration fee, about seven times the fee for a normal sedan, Bloomberg reported Thursday.

The proposal is mainly targeted at heavy-duty pickups and other large internal-combustion vehicles, but it could also impact EVs, with battery packs often adding weight compared to internal-combustion vehicles of comparable footprint.

2022 GMC Hummer EV

2022 GMC Hummer EV

Mary Cheh, a D.C. councilmember who developed the proposal, said in an interview with Bloomberg that EVs would be subject to the same sliding scale of registration fees, but with a 1,000-pound credit to avoid discouraging EV adoption.

But even that won't help all EVs. The 2022 GMC Hummer EV pickup's battery pack weighs 3,000 pounds, or about a third of its roughly 9,000-pound curb weight. It shows how weight-based rules can impact both safety and efficiency considerations.

Current footprint- and weight-based fuel economy rules are based on a perceived association between size, weight, and safety—which puts regulation partly in the hands of the National Highway Traffic Safety Administration (NHTSA).

2022 GMC Hummer EV

2022 GMC Hummer EV

Not everyone agrees that lighter cars reduce safety, however. EVs and hybrids are required to comply with EPA quiet car rules aimed at alerting pedestrians. Heavy-duty pickups driven in urban areas are off the hook because it's assumed their engine noises will be a sufficient warning to pedestrians.

We don't need a lot of vehicles like the 9,000-pound Hummer EV, but it does challenge the validity of those associations—like that the Hummer EV and gigantic SUVs are essentially as greenhouse gas-efficient as smaller gasoline cars.

The other aspect is the additional damage that these vehicles do to the streets—the basis for much debate around whether road taxes should be higher for the heaviest personal vehicles. It feeds into the longtime push from a range of U.S. business interests to raise the federal gas tax—although with pump prices soaring, that might be a moot point now.