While most drivers have to empty their pockets in search of meter money for downtown parking, some cities are offering free parking to drivers of fuel-efficient vehicles. The benefits, municipal officials say, include less air pollution and oil consumption, as well as increased environmental awareness. But others are concerned that the incentives are counterproductive, adding more cars while discouraging carpooling and public transit.

So-called “green” vehicles — including gas-electric hybrids and cars powered by compressed natural gas, biodiesel or other alternative fuels — have become more popular in recent years, especially as oil and gas prices have skyrocketed. In 2005, more than 200,000 hybrids were sold in the United States alone, and the automobile industry estimates that between 600,000 and 1 million hybrids will be sold by 2010.

Supporting the trend, local governments in Salt Lake City; New Haven, Conn.; Fresno, Calif.; Albuquerque, N.M.; and Austin, Texas, now are offering free parking incentives to encourage their residents to purchase green vehicles. In Salt Lake City, free metered parking is available to residents whose vehicles get 50 miles per gallon, have low emissions or are powered by an alternative fuel. Utah also offers tax credits for residents who buy clean fuel vehicles and allows those vehicles to use high-occupancy vehicle (HOV) lanes.

“In the wake of record oil prices, consumers and fleet managers are looking for relief on ways to meet the energy challenges we face,” says Beverly Miller, executive director of the Utah Clean Cities Coalition, which worked with Salt Lake City to implement the new incentive. “There's no need to wait. Real alternatives are available now.”

In July 2005, New Haven launched a one-year trial for its “Green Park” program, which has seen small but growing interest. About 30 vehicles are participating in the program, which features free metered parking for hybrid and alternative-fuel vehicles. However, the city limits participation to those who live and pay taxes in New Haven and only allows people to park for the allotted metered time. Requests for free parking from commuters who only work downtown and those who wanted free all-day parking were declined.

Officials say the program, which is up for renewal this summer, is working, but they acknowledge potential concerns. “We wanted to show that the city recognized that there were alternative fuels out there, and we wanted to provide some kind of benefit for those drivers,” says Charles Wailonis, New Haven's parking enforcement administrator. “At the same time, we have to be cautious and not alienate people who don't have fuel-efficient vehicles.”

In Baltimore, residents who own Toyota Prius, Honda Insight and Civic Hybrid models can buy parking passes at city-owned garages at up to half of the regular rate. The city is considering offering free metered parking and other incentives as well.

Baltimore also recently joined a grassroots coalition of cities — including Denver, Los Angeles, Austin, San Francisco and Seattle — to urge automakers to accelerate the development of plug-in hybrid electric vehicles. Those vehicles can accommodate larger batteries that would improve the typical hybrids' reliance on gasoline. Plug-ins are recharged using a standard wall socket to “refuel” at about 75 cents per gallon, depending on electricity rates.

Austin Mayor Will Wynn has pledged $1 million in rebates to encourage residents and businesses to purchase plug-in hybrids. The city currently offers a $100 parking card that “green” vehicle drivers can use at all city meters.

At the same time, transportation officials and environmentalists are concerned that the incentives, such as allowing hybrids into HOV lanes, simply clog traffic and discourage carpooling or public transit. “Allowing hybrid vehicles into carpool lanes is likely to destroy the intended benefits of those lanes, which is to offer a faster and more reliable trip to those who put less burden on the highway by sharing rides,” says Robert Poole, director of transportation studies at the Los Angeles-based Reason Foundation. “Besides, we already have generous federal and state tax breaks for hybrids. Letting hybrids into HOV lanes is overkill.”

Although financial and environmental questions remain, for now it appears that green-vehicle incentives will continue. “Those who have purchased hybrids are pleased that municipalities have done something good for the environment,” Wailonis says. “Anything we can come up with to encourage people to look at different technologies is beneficial.”

Kim O'Connell is a freelancer based in Arlington, Va.