A Southern California motorist drove off the lot of a Hyundai Motor Co dealership on Tuesday in a zero-emissions car touted by the automaker as marking the commercial debut of mass-produced hydrogen fuel-cell vehicles in the United States.

State energy and air-quality officials hailed the occasion in Tustin, California, about 35 miles (56 km) southeast of Los Angeles, as a milestone in efforts to curb tailpipe pollution that accounts for about a third of California's greenhouse gas emissions.

Independent industry analysts were less breathless about the announcement, noting that other automakers, including Honda Motor Co Ltd and Mercedes-Benz, have already put fuel cell vehicles on the road, albeit in very limited numbers.

They said the relatively high cost of building the cars and extremely low number of hydrogen refueling stations would constrain the market for such vehicles for years to come. But they credited South Korean-based Hyundai with making a high-profile commitment to a promising technology.

"That's a big deal," said industry analyst Maryann Keller, of Maryann Keller & Associates of Greenwich, Connecticut.

In a ceremony at Tustin Hyundai, dealer principal John Patterson handed the keys for the new Tucson fuel cell-powered crossover vehicle to its first U.S. customer, Timothy Bush, who is leasing the car for $499 a month plus a $2,999 down payment.

As an added incentive for early adopters, the three-year, 36,000-mile lease term also come with unlimited free hydrogen refueling and free maintenance service at any of one of three participating dealerships in Southern California. The cars are not yet available for sale, company officials said.

The Tucson fuel cell, which comes only in white, is virtually identical to the gasoline version of the CUV, a four-door automobile with a rear hatch, and is manufactured on the same assembly line at Hyundai's Tucson plant in Ulsan, South Korea.

With a driving range of 265 miles for each fill-up and minimal cold-weather effects, the vehicle compares favorably to plug-in battery electric cars. Refueling takes about 10 minutes.

Showing off the car to reporters, Bush said the Tucson's range and size offer versatility similar to his current sport utility vehicle. "I'm really excited to be able to pack up the kids and the dog and surfboards in the back and go to the beach or head up the local mountains, which we can totally do in this car," he said.

The fuel cell produces power from hydrogen gas through a electrochemical process that involves no combustion or moving parts. Its only tailpipe emission is water vapor.

Hyundai has declined to say how many fuel cell vehicles it plans to make this year, or how many have been ordered.

Potential customers must live within range of nine existing refueling stations in Southern California, most of them along the Interstate 405 corridor through Los Angeles and Orange counties.

California aims to have 1.5 million zero-emissions vehicles, which include fuel cell cars, on its roads by 2025.

Copyright: Thomson Reuters 2014