Ford`s hydraulic hybrid could undercut electric EVs

A fleet of prototype vehicles, powered by a hybrid drive system linking hydraulics to a petrol engine, could be on US roads by the end of the decade. Ford and the US Environmental Protection Agency (EPA) are developing the technology together, and claim that it could offer cost and performance advantages over electric hybrid systems.

Instead of the motor-generator and batteries used to store energy in a hybrid-electric drive system, the new system uses hydraulic motors and pumps to recover energy from the high-efficiency engine and brakes, and stores this in accumulators. Ford and the EPA say that the system could be more efficient than electric storage and that the tanks should be lighter and cheaper than batteries. The hydraulic technology is also expected to produce more torque than an electric system.

The technology was originally developed and patented by the EPA`s National Vehicle and Fuel Emissions Laboratory in Michigan. It was refined under an earlier agreement with Ford. The two partners will both contribute personnel, and will share the costs of the new project, which are expected to run into millions of dollars. Others involved in the project include the Eaton Corporation and FEV Engine Technology.

The technology will probably be used initially to improve the fuel economy of small trucks and SUVs (sports utility vehicles).

"Hydraulic hybrid technology holds great promise for our customers and for our society," says Gerhard Schmidt, Ford`s vice-president for research. But he adds that "significant hurdles remain" in developing and proving the technology.