Last week, Chrysler and the United States' Environmental Protection Agency (EPA) announced they would cooperate on adapting a hydraulic hybrid drive system for the company's people movers.
The EPA owns the patent on hydraulic hybrid systems and currently is testing the concept in large commercial vehicles, such as UPS's courier vans. Ford and the EPA developed a hydraulic hybrid diesel SUV in 2004 that was cited as getting 85 per cent better fuel economy.
In current use, the hydraulic hybrid system stores kinetic energy in hydraulic fluid tanks, releasing the pressure to drive a vehicle's wheels. Similar to an electric hybrid, if there is enough pressure in the system, the engine can shut off when the vehicle is stopped. Hydraulic pressure provides a boost for acceleration and can get the vehicle moving from a stop. The EPA says overall fuel economy increases 30 per cent with the system, while city economy increases 60 per cent.
For the Voyager people mover, Chrysler envisions a series hybrid application, where hydraulic pressure is the only force turning the wheels. That pressure is created through regenerative braking and from a 2.4-litre four-cylinder petrol engine. The hydraulic fluid tank, referred to as an accumulator, holds 55.5 litres at 34,500kPa or about 340 times atmospheric air pressure.
The main challenge for Chrysler and the EPA in this new project is to make the system more compact, taking it down from its commercial size deployments to a size that can be fitted into a passenger vehicle.
Don't expect to see a hydraulic hybrid Voyager on the market anytime soon. Chrysler is exploring multiple fuel-saving technologies, some of which come from new owner Fiat.
Via CNET US