The United States Environmental Protection Agency (EPA) has unveiled the first-ever series hydraulic hybrid diesel urban delivery vehicle, which will provide improvements in fuel economy and emission reductions.
Development of the hydraulic hybrid is the result of a partnership between the EPA, U S Army, UPS, International Truck and Engine Corp, and Eaton Corp.
The EPA and UPS plan to evaluate the vehicle's fuel economy performance and emissions during a series of tests in 2006. In laboratory testing, the EPA's patented hydraulic hybrid diesel technology achieved a 60% to 70% improvement in fuel economy and more than a 40% reduction in carbon dioxide emissions, compared with a conventional UPS vehicle.
The EPA estimated that when manufactured in high volume, the added costs of the hybrid components could be recouped in less than three years through lower fuel and brake maintenance costs.
In the series hydraulic hybrid diesel, a high-efficiency diesel engine is combined with a hydraulic propulsion system, replacing the conventional drivetrain and transmission. The vehicle uses hydraulic pumps and hydraulic storage tanks to store energy, similar to what is done with electric motors and batteries in hybrid electric vehicles. Fuel economy is increased in three ways: vehicle braking energy is recovered that normally is wasted; the engine is operated more efficiently; and the engine can be shut off when stopped or decelerating.
The diesel hydraulic hybrid truck is potentially eligible to qualify for a tax credit that is up to 40% of the incremental cost of the vehicle under a provision of the Energy Policy Act of 2005 for medium- and heavy-duty vehicles.
UPS will test the hydraulic hybrid for the next several months. It will be used on a city route in the Detroit area, making daily deliveries to homes and businesses.