An Earth Day wish: Bring hydro cars to Mass.

Three major automakers currently manufacture cars that could help Massachusetts reduce greenhouse gas emissions and give motorists a broader range of choices in zero-emission vehicles.

There’s just one problem: Toyota, Honda, and Hyundai don’t sell or lease their fuel-cell vehicles here yet, because we don’t have the network of hydrogen fueling stations that would make them viable.

So here’s one very practical hope for Earth Day: The state should follow California’s lead and help build out the required stations. They work just like traditional gas stations, but the cars that fill up at hydrogen pumps emit only water, with no greenhouse gases.

The need should be obvious: According to state data, transportation accounts for a whopping 43 percent of the state’s greenhouse gas emissions, more carbon pollution than from electricity generation and the heating of residences combined. In coming years, a key part of reducing the state’s emissions will be convincing drivers to switch to cleaner cars.

Right now, though, the only viable choice for zero-emission cars are battery-powered electric vehicles. So far, they’ve had limited penetration: In 2017, there were 12,000 battery-powered vehicles on the road, out of 2.4 million cars registered in the state.

Both battery and hydrogen cars could have a place in the auto market of the future, just as gas and diesel coexist now. The key is to give consumers choices. Many drivers will be just fine with battery-powered cars, whose prices are falling. Fuel-cell cars are for now more expensive, about $60,000. But one advantage is that they fill much faster than a battery charges. If you’re an Uber driver who can’t afford to spend hours charging your car, that might be the feature that changes your mind and makes you comfortable ditching gasoline.

Looking further into the future, hydrogen might also be a better option for larger vehicles like trucks and heavy construction equipment, which would need prohibitively large batteries. They also might make a better fit in dense cities where building enough chargers for battery cars would be challenging. China, which spent the last decade subsidizing battery cars, recently slashed battery subsidies and pivoted to hydrogen instead.

Neither technology has any tailpipe emissions, but their overall carbon footprint depends on how their fuel — electricity or hydrogen — is produced. Battery-powered cars are as clean as the electricity that charges them. Likewise, hydrogen produced from clean sources makes for an extremely clean alternative to gasoline-powered cars.

So what can Massachusetts do to entice car manufacturers to make their hydrogen vehicles available here faster? The cars are already eligible for the same rebates as battery-powered vehicles.

But California, which also provides rebates, went a step further by helping build out a network of fueling stations, which now stands at 39 stations for the entire state. That’s helped put over 6,000 hydrogen cars on the road there, which typically get more than 300 miles to a tank. Massachusetts could use some of its funds from the Volkswagen settlement to subsidize stations and hasten the cars’ availability.

So far, Toyota and Air Liquide have built stations in Hartford, Providence, and Mansfield, with another nearing completion in Braintree, in preparation for selling fuel cell cars here.

Edmond Young, hydrogen fuel infrastructure manager at Toyota, said the company needed a few more hydrogen stations in the area before it could market its fuel cell car, the Mirai, in Massachusetts, and was hoping to make the car available in a year to a year-and-a-half. “We’re very excited about the market,” he said.

Derek Joyce, a Hyundai spokesman, said the automaker’s long-term plan is to expand the availability of its fuel-cell car, but that there was no specific timetable for marketing Hyundai’s Nexo in Massachusetts. “The infrastructure in the Northeast is limited at this time, and we look forward to its growth,” he said.

So should Massachusetts consumers who want the widest array of options for clean cars.