Three years ago, Ross Marabella put down a reservation for the Tesla Model 3. He was eager to swap out his 2005 Honda Accord.

Tesla finally delivered the vehicle last year, and Marabella was delighted to realize that charging stations had proliferated during the long wait.

“It’s getting better and better to own one of these vehicles,” said Marabella, who doesn’t have a charger at his San Francisco home but often plugs in at a station near his Novato office.

Partly because of the arrival of the Model 3, electric car sales locally have surged. In 2018, electric cars accounted for 13% of new passenger vehicle registrations in the Bay Area, up from 7% in 2017. The huge Los Angeles metro area has more electric vehicles overall, but its numbers grew more slowly.

Nic Lutsey, a program director in San Francisco for the International Council on Clean Transportation, a nonprofit that provided the figures, said electric cars used to be so rare that he and his colleagues would buy a beer for whoever first spotted a new entrant, like the Model 3.

“Now there are so many models ... that we can’t play as many of those games,” he said.

The council’s data includes plug-in hybrids. But the majority — like the Model 3, which accounted for 39% of Bay Area new electric vehicles last year — are all-electric. (The Bay Area in this instance is defined as Alameda, Contra Costa, Marin, San Mateo and San Francisco counties.)

Hefty incentives have helped spur purchases. Marabella, for example, said he got a $7,500 federal tax credit and a $2,500 rebate from California.

Clean-car drivers can also get carpool-lane privileges in California. At last count — in 2016 — about 8% of carpool lane occupants on Bay Area highways were low-emissions vehicles, according to a Metropolitan Transportation Commission study. (That’s a lower number than for scofflaws, the study found.)

Using the “carpool lane to get on the Bay Bridge is nice,” said Mitchell Barnow, a San Franciscan who bought a Model 3 last year.

Perhaps most crucially, electric cars’ range — how far they can go on a single charge — has increased to more than 200 or even 300 miles in some cases. And cities and highways have added charging stations. In the San Francisco metro area, the number of public charging outlets rose to more than 2,700 by the end of 2018 — up 39% from a year earlier, according to Lutsey’s group. The number of workplace outlets in the region rose more than 50% over that time frame.

Barnow has taken his car to Yosemite and had no trouble plugging in en route at the Tesla Supercharger station in Groveland (Tuolumne County).

“You stop, have lunch, and it’s no big deal,” he said.

Still, to more fully replace gasoline and diesel vehicles, he believes that even faster charging and more stations will be critical.

“It’s got to take five minutes, so people can just charge, charge, charge,” he said.

California has a target of 1.5 million zero-emission vehicles on the road by 2025, and Lutsey and other environmentalists believe the state is on track. He also expects the state to hit a more ambitious goal, of 5 million by 2030.

Another incentive could soon surface for Californians: Pacific Gas and Electric Co. and other electric utilities may offer rebates to electric car buyers, potentially amounting to $1,500 to $2,000, according to Don Anair, deputy director of the Union of Concerned Scientists’ clean vehicles program. Unlike the existing rebate from the state, which can take months to arrive in the mail, the cash from the utilities would be available instantly, at the dealership. The California Public Utilities Commission still needs to approve the plan.

Still, the road ahead will have bumps. The federal tax credit for electric cars has been shrinking for some buyers. Buyers of a Model 3 can no longer get a $7,500 federal credit. Now it’s $3,750 — half — and it will fall further, to $1,875, in July. That’s because Tesla has sold so many cars that the company hit a cap for the credit (legislation under consideration in Congress would raise the cap). Buyers of GM cars such as the popular, all-electric Chevrolet Bolt have also seen their federal credit slashed to $3,750; it will fall to $1,875 come October.

Within California, lawmakers have recently imposed more limitations on clean vehicles’ access to carpool lanes. For example, high-income buyers must now choose between a rebate and carpool lane access.

The bigger issue is that despite gains in San Francisco and other metro areas, clean cars still account for only a fraction of California vehicles. Even in the Bay Area, Lutsey estimates that a little more than 3% of all light-duty vehicles on the roads are electric. Only a few big cities would have a higher proportion — like San Jose, where Lutsey calculates that the equivalent figure is just over 5%.

People hold onto their gas guzzlers for years, in other words. And that jeopardizes California’s climate goals: Even though the state’s overall greenhouse gas emissions have fallen, pollution from the transportation sector has ticked up. More people are coming to California, and the total number of miles being driven on Bay Area and California roads is rising.

But as the technology continues to improve and more people own electric cars, they may entice friends and neighbors to join the trend. “More EVs begets more EVs,” Lutsey said, using the abbreviation for electric vehicle.

That rings true for Max Goshay, a Marin County resident who bought a Model 3 last year and uses it to drive for Uber.

“I’ve probably sold a few Teslas ... because of how many conversations I’ve had with people about the car,” he said.

Kate Galbraith is the San Francisco Chronicle’s assistant business editor. Email: kgalbraith@sfchronicle.com Twitter: @kategalbraith