Chrysler Group LLC and the U.S. Environmental Protection Agency said Wednesday that they are working together to commercialize an unusual type of hybrid-vehicle technology aimed at reducing fuel consumption.

Under the partnership, Chrysler will work to produce vehicles using a hydraulic hybrid system developed by the EPA. The system recovers energy as a vehicle brakes and uses the resulting hydraulic pressure to help power the vehicle.

That differs from today’s hybrid cars, which combine batteries and electric motors with traditional gasoline engines to boost fuel economy.

The hydraulic technology is used in some large delivery trucks and industrial applications and has the potential to improve a vehicle’s fuel economy by 30 percent  to 35 percent, said EPA Administrator Lisa Jackson.

Chrysler aims to develop a test vehicle using the hydraulic hybrid system by November  and hopes to complete testing and evaluation by July 2012, said Chrysler Chief Executive Sergio Marchionne.