WASHINGTON (AP) — The federal government would provide grants to help cities build the infrastructure needed to support electric vehicles and to offer new tax credits for buyers of those cars under legislation introduced Thursday in Congress.

The bills in the House and Senate are designed to smooth the way for the electric vehicles that are expected to start showing up at car dealerships in large numbers this fall. Supporters hope to add 700,000 vehicles to the road that are powered largely by electricity in the next several years.

The legislation will lead to "broad-based deployment of electric vehicles in this country," said Sen. Byron Dorgan, D-S.D., one of the main sponsors of the Senate version that has an overall cost of $10 billion.

The government has several programs to spur the development of vehicles that use little or no gasoline. That includes federal tax credits of up to $7,500 for the purchase of an electric vehicle and up to $25 billion in loans earmarked for manufacturers of alternative fuel technologies.

The Senate bill would allow up to 15 municipalities and cities to apply to the Department of Energy for grants of up to $250 million to build infrastructure such as public recharging stations. The House version offers $800 million to five communities.

The Senate would let buyers in those areas to take an additional $2,500 credit for the purchase of an electric vehicle, bringing the total credit to $10,000. The House version gives a credit of up to $2,000 for electric vehicle owners to buy and install charging equipment.

The Senate version also proposes $1.5 billion for research with the goal of inventing technology such as a battery that can go 500 miles on a single charge.

Most electric vehicles rely on batteries rather than gasoline engines for power, though some hybrids combine the two. The batteries are recharged by connecting the vehicle to an electrical outlet.

While most home owners could plug their car into a wall outlet, city dwellers would have a harder time finding ways to recharge their cars since few towns and urban areas have a network of public charging stations.

This is considered a major obstacle for the widespread adoption electric vehicles, which are ideal for city drivers, who usually take shorter trips that would not exhaust the relatively short range of the batteries.

Chevy Volt, for example, which General Motors plans to sell in November, can get up to 40 miles on the battery before a small gas engine kicks in to recharge it. The Nissan Leaf, a purely electric vehicle expected to be sold by the end of the year, can travel up to 100 miles before needing to be plugged in.