On Oct. 27, UPS announced its first purchase of seven hydraulic hybrid vehicles that promise dramatic fuel savings and environmental benefits.

The technology, originally developed in a federal laboratory of the Environmental Protection Agency, stores energy by compressing hydraulic fluid under pressure in a large chamber. UPS was the only company in its industry asked to road-test the technology two years ago and now becomes the first delivery company to place an order for hydraulic hybrid vehicles.

Road testing results show the prototype vehicle achieved a 45-to-50 percent improvement in fuel economy compared to conventional diesel delivery trucks. UPS believes similar fuel economy improvements and a 30 percent reduction in CO2 are achievable in daily, real-world use. The EPA believes the technology can perform equally well in other applications such as shuttle and transit buses and refuse pick-up trucks.

UPS will deploy the first two of the new HHV’s in

during the first quarter of 2009. Eaton, which helped develop and refine the vehicle’s hydraulic hybrid power system, will monitor the vehicle’s fuel economy performance and emissions in the

area. The additional five HHV’s will be deployed later in 2009 and early 2010.

The EPA estimates that when manufactured in high volume, the added costs of the hybrid components can be recouped in less than three years through lower fuel and brake maintenance costs.

UPS’s current “green fleet” totals more than 1,600 low-carbon vehicles, including all-electric, hybrid electric, compressed natural gas (CNG), liquefied natural gas (LNG) and propane-powered trucks.