The city of Boston today will unveil three electric-vehicle charging stations near City Hall Plaza, providing exclusive downtown parking — complete with a power boost — for those who drive the environmentally friendly cars.

By putting the stations in a high-profile location, the city hopes to encourage drivers to abandon gasoline-powered vehicles and adopt the emerging electric option.

For the regular $1.25-an-hour price of feeding the parking meter at three designated spots on Cambridge Street, drivers will be able to juice up their gas-free vehicles there for no additional cost.

The charging stations look like boxy, modern parking meters with one significant difference: an 11-foot-long power cord coiled neatly at the front.

“The idea with these three charging stations is to get a sense of how they are used,’’ said Veneet K. Gupta, the director of policy and planning for the Boston Transportation Department. “In the long term, we want to explore a citywide program. But we want to do that so it’s timed with the market as more and more people are buying electric vehicles.’’

With a $7,500 federal tax rebate for buyers and other encouragement from the White House, automakers have begun aggressively pushing all-electric cars. While the popularity of hybrid cars, which run on a combination of gas and electricity and don’t need to be charged, has grown steadily in recent years, use of fully electric cars remains low.

But more are on the way. The Nissan Leaf is expected to be available here this fall and 2,000 have been ordered in the Boston area, City Hall officials say. General Motors also plans to introduce the Chevy Volt to New England this fall and has ambitions to sell 15,000.

“This is here, it’s happening now,’’ said Andy Chu, a vice president of Watertown-based A123 Systems Inc., which makes a new kind of lithium ion battery for electric vehicles. “It’s not just [research and development], it’s not some high-tech curiosity.’’

People who regularly see vehicles recharging on Cambridge Street will begin to see electric cars as “a very natural thing,’’ said Chu, whose company expects to manufacture enough batteries to power the equivalent of 30,000 electric vehicles.

Boston officials have been encouraging developers to include a minimum of five charging stations with all new buildings. One charging station has been in use at the Seaport Boston Hotel for more than a year, city officials said. Another five were included in a new building on Clarendon Street in the Back Bay and more are on the way.

Boston is not the only city to push the new technology. Mayor Edwin M. Lee of San Francisco issued an executive directive earlier this month to install more than 80 electric vehicle charging stations in his city over the next two years. That initiative will cost an estimated $500,000.

Boston’s plan for three public outlets is comparatively modest. Manufactured by Coulomb Technologies, the ChargePoint electric stations each cost roughly $4,500, city officials said.

The stations offer two power levels — 110/120 volt and 240 volt — to accommodate most electric vehicles. Electricity is expected to run $15 a month for all three units, Gupta said, and will vary with usage. The city will cover that expense.

But there will be another cost. Drivers of gas-powered vehicles will lose three prime parking places in the heart of Boston. A ticket for a gas-powered car parking in an electric-car space will run $55.

“This is something we discussed and we felt that the overall purpose of encouraging electric vehicles outweighed any issues about taking up three public spaces,’’ Gupta said. “There are lots of public garages, so it’s not like there are no spaces at all.’’

Andrew Ryan can be reached at acryan@globe.com.

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