The HHV cars were developed by Freightliner Custom Chassis Corp. and Parker Hannifin Corp. According to UPS, they will result in a 35-percent improvement in fuel economy, and up to a 30-percent reduction in carbon dioxide emissions, compared with traditional diesel-powered vehicles equipped with automatic transmissions. The deployments are supported in part by grants from the U.S. Department of Energy's Clean Cities program. The Baltimore units will be put into service immediately, with the Atlanta vehicles to be introduced by the end of 2012. UPS currently has one HHV operating in Laguna Hills, Calif. The vehicles operate on two power sources - a diesel combustion engine and advanced series hydraulic hybrid. The driver can turn off the engine and use stored energy to propel the vehicle, reducing engine run time on a typical route by up to 90 minutes. Because the HHV's efficiency relies on constant braking, the vehicles are best suited for urban routes, UPS said. The company currently operates 2,593 vehicles that are powered by alternative fuels or technology.
