In partnership with the US Environmental Protection Agency, UPS will begin testing a small fleet of hydraulic hybrid delivery trucks in the United States. The new vehicles can achieve 50-70% better fuel economy, a 40% reduction in greenhouse gas emissions, and pay for their extra expense in less than 3 years.
UPS will field two hydraulic hybrids in Minneapolis, MN, in early 2009 and an additional five hydraulic hybrid trucks will be deployed later in 2009 and early 2010. Although this sounds like a tiny fleet, keep in mind that this is the largest scale commercial test of hydraulic hybrids ever conducted.
The UPS hybrid hydraulic truck is a standard-looking 24,000 pound package car, with an EPA-patented diesel series hydraulic hybrid drive attached to the rear axle.
In a series hydraulic hybrid, the conventional drivetrain is replaced with a hydraulic system that stores energy by compressing gas in a chamber using hydraulic fluid. It works in much the same way that a hybrid electric car does — a small, efficient motor generates power which gets stored for later use — only, the way energy is stored in a hydraulic hybrid is in a pressurized chamber rather than in a battery.
The hydraulic hybrid drivetrain eliminates the need for a conventional transmission and increases fuel economy in three ways:
- A large amount of the energy that is otherwise wasted in braking can be recovered to pressurize the hydraulic fluid.
- The engine operates much more efficiently — similar to a hybrid electric car, only without the bulky batteries
- The engine can easily be shut off and instantaneously restarted during regular driving — such as when the vehicle is slowing down or stopped at a light.
UPS has been developing what it calls its “green fleet” over the last several years and currently has more than 1,600 low carbon emissions vehicles including electric, hybrid-electric, compressed natural gas, liquefied natural gas, and propane trucks.
Although this is a small step, I applaud UPS for testing the waters. Hopefully others will join in quickly.
Source: UPS press release
Image Credit: UPS