A coalition of 17 states, as well as the District of Columbia and Canadian province of Quebec, plan to electrify 30% of new trucks and buses in their jurisdictions by 2030.

That's the initial goal of an action plan drafted and adopted by those jurisdictions, which also sets the goal of making 100% of new truck and bus sales zero-emission no later than 2050.

The full list of states that have signed onto the plan includes: California, Colorado, Connecticut, Hawaii, Maine, Maryland, Massachusetts, Nevada, New Jersey, New York, North Carolina, Oregon, Pennsylvania, Rhode Island, Vermont, Virginia, and Washington.

Proterra Catalyst electric bus

Proterra Catalyst electric bus

Vehicles covered by the plan include medium-duty and heavy-duty commercial vehicles, ranging from pickup trucks and vans to long-haul trucks, along with school buses and transit buses. These vehicles account for a large share of transportation-related emissions, but have not received as much regulatory attention as passenger cars.

"Combustion trucks and buses make up only 10% of total vehicles on our roads, but represent a third of climate-disrupting greenhouse gas pollution and a majority of nitrogen oxide (NOx) pollution in the transportation sector," the Sierra Club said in a statement expressing support for the plan.

California has already moved to regulate commercial-vehicle emissions. Its Advanced Clean Trucks rules will require a certain percentage of advanced-technology trucks, while the Omnibus rules set emissions levels for the whole fleet. The latter have already been challenged by a lawsuit from the Truck and Engine Manufacturers Association, alleging manufacturers weren't given enough lead time.

Volta Zero 7.5-tonne (front) and 16-tonne electric trucks

Volta Zero 7.5-tonne (front) and 16-tonne electric trucks

That lawsuit has created a divide among truck makers that's not unlike the divide that existed between automakers several years ago, when Toyota, General Motors, and others chose to stand with the Trump administration in opposing cleaner vehicle rules. Ford, General Motors, and Daimler Trucks, for instance, are members of the Truck and Engine Manufacturers Association, but they have been pushing for more electric commercial trucks.

This follows criticism from a wide range of groups that federal rules for trucks don't look beyond tailpipe emissions—and don't yet factor in the importance of the shift to zero-emissions tech. Meanwhile, a recent Supreme Court decision potentially raises concerns over any kind of emissions regulation.