EPA-Influenced Vehicles Get Set to Hit Road
Agency Inspires Commercial Manufacture Of Fuel-Saving, Hydraulic-Hybrid System in Trucks
By JOHN J. FIALKA
Wall Street Journal
August 22, 2006; Page A4
ANN ARBOR, Mich. -- After badgering American manufacturers to produce cleaner, more-fuel-efficient vehicles, the Environmental Protection Agency is about to see its first product hit the streets.
The engineers at the EPA's National Vehicle and Fuel Emissions Laboratory here have built and tested many prototypes over the years, including a diesel-hydraulic passenger car that gets more than 80 miles per gallon. But the first EPA-influenced product to travel beyond the laboratory will be a garbage truck.
The garbage truck -- slated for rollout next year -- is a hybrid vehicle. Most hybrids use two power sources. In this case, the garbage truck will tap a diesel-burning engine and a hydraulic pump.
Soaring gasoline prices are pushing American auto buyers into showrooms for more-efficient vehicles, but the impetus is stronger among buyers of big trucks, says Bradley F. Bohlmann, a marketing manager for Eaton Corp. The Cleveland company will begin producing and selling the hydraulic-hybrid-transmission system pioneered by the EPA lab next year. The systems will be installed in truck bodies assembled by Peterbilt, a division of Paccar, Inc., of Bellevue, Wash.
Peterbilt in turn will market the garbage trucks and has targeted both the private sector and municipalities as sales prospects. Among U.S. cities, Chicago, Houston and Los Angeles have indicated the greatest interest thus far, according to Peterbilt.
The garbage truck, which stores and reuses energy normally lost in the braking process, will increase fuel-efficiency as much as 30%, Mr. Bohlmann predicts. Following the garbage truck may be a parade of yet more-efficient vehicles, starting with delivery trucks used by United Parcel Service Inc., which is testing two hydraulic-hybrid vehicles.
In the UPS trucks, the vehicle's entire mechanical-transmission system and drive shaft are replaced with a hydraulic system that delivers power from its diesel engine to pump motors that turn the rear wheels. Robert Hall, environmental manager for UPS, says the hydraulic hybrids may be less expensive and easier to maintain than hybrid gasoline-electric vehicles, which rely on batteries to store energy. UPS spends $2.1 billion a year on fuel, Mr. Hall says.
Other big truck buyers, including the Army and the Postal Service, are interested. And the Chinese government has been in touch with the EPA about using the technology to power a fleet of hydraulic-hybrid buses for the 2008 Olympics.
Such commercial interest is unusual for the EPA lab, which has seen many of its ideas shelved or abandoned. The lab's primary function is testing vehicles to ensure they meet EPA emission standards, but since 1970 it has kept a small unit of engineers and technicians working on ideas for cleaner, more-fuel-efficient cars. The Advanced Technology Division, which worked on hybrid gasoline-electric vehicles in the 1970s, decided in the late 1980s that hydraulic hybrids would be even more efficient.
"We felt strongly we shouldn't abandon the idea," says Christopher Grundler, director of the lab, who credits Charles Gray Jr., an automotive engineer who runs the advanced section, for persevering. "We never wanted to be a hobby shop, working on things that nobody wanted," Mr. Gray says.
Mr. Gray's theory was that hydraulic-drive systems, commonly used in heavy-construction equipment, could be adapted for other vehicles, especially those that make frequent stops. Using so-called regenerative braking systems, electric hybrids capture about 25% of the power lost in braking and store it in batteries. A hydraulic system, using pistons to capture the wasted energy by compressing nitrogen gas stored in a tank, can capture as much as 75% of the wasted energy. When the nitrogen is allowed to expand, it pushes hydraulic fluid that helps the engine turn the rear wheels.
In the late 1980s, then-Vice President George H.W. Bush was interested in the idea, which in 1993 became part of the Clinton administration's quest for the "Supercar." That was a voluntary research effort among U.S. auto makers and government labs to build a passenger car that could get 80 miles a gallon and be ready for production by 2004. Toyota Motor Corp. asked to join the program but was rejected and went on to develop its Prius hybrid electric car.
"The drive system [Toyota] produced looked like the one we developed in the 1970s," says Mr. Gray, who recalls the results of the EPA program were published before it was dropped for other priorities. David Hermance, executive engineer for Toyota's U.S. Technical Center, said the Prius was developed from Toyota's own research but added that it "would certainly be accurate" to say that the goals of the government's Supercar program spurred the Prius's development. Toyota has sold more than 372,000 of its hybrid electric cars in the U.S. since 1999.
But superefficient cars drew scant attention from U.S. auto makers and consumers in the late 1990s. To spur them, Mr. Gray's lab used spare parts to build a hydraulic hybrid with a Volkswagen diesel engine. The vehicle, which was about the size of a Ford Taurus and looked like a dune buggy, got 80 mpg. It sank in 2001 when the Supercar program was abandoned. The current Bush administration shifted government research to the "Freedom Car," which would use hydrogen-powered fuel cells.
Mr. Gray's team was allowed to press on in a joint venture with Ford Motor Co., which announced it would use the EPA technology to improve the fuel economy of light-duty trucks and sport-utility vehicles. Ford and EPA scientists developed a hybrid-hydraulic Ford Expedition, a big SUV that got more than 27 mpg in city driving. Then in 2004, Ford withdrew, opting instead for a licensing agreement with Toyota that allowed it to build hybrid-electric vehicles. "We definitely think hydraulic hybrid has merit," says Nick Twork, a technology spokesman for Ford, "but we decided that it wasn't going to be on the top of our list."
"You can't imagine the grieving we did when Ford left," Mr. Gray recalls. "We were that close," he said, to making production vehicles.
The EPA lab still hopes to prod consumers toward the 80-mpg passenger car, using the new heavy-truck prototypes. As Mr. Gray explains it: "There is a good chance of that happening if people look at the UPS truck sitting next to them at a stoplight and realize that it's getting better mileage than some of the vehicles they're driving."