Kasmer�s �hydristor� is drawing interest from heavy equipment makers.

Tom Kasmer believes he can save the Earth with the power of hydraulics. The Binghamton, N.Y.-based inventor wants to use his patented “hydristor” powertrain to clean up the millions of cars and trucks on the road. He also thinks he can make construction equipment operate more efficiently and become less polluting. But there’s one little catch: While Kasmer’s high-pressure hydraulic transmission has been sitting on the drawing board for over a decade, few manufacturers have shown real interest in testing it out. “I could save the auto industry if they’d only listen,” Kasmer says.

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Kasmer is one of many visionaries trying to clean up the combustion engine, as fuel prices, energy security and global warming become more politically charged. The fuel of the future for work trucks and heavy equipment, which make up the lion’s share of the construction industry’s day-to-day pollution, is barely in sight. In 20 years, will off-road vehicles and trucks run on zero-emission hydrogen fuel cells? Or will biomass synthesized from forestry waste power the industry’s bulldozers? No one knows for sure. What scientists can say is that they are betting on several “horses” to win the race. Aside from research, economic policy will set the wheels in motion, they say.

“If the approach is not profitable, it’s not going to be implemented,” says Vijay K. Sethi, vice president of energy production and generation at Laramie, Wyo.-based Western Research Institute. Monetary incentives, such as public tax credits, already have helped alternative power sources, such as hybrid vehicles, gain traction.

Developing sustainable equipment is a tricky game. Scientists have limited funds to throw around, so they make a wager on a few promising ideas. Manufacturers understandably are reluctant to retool their designs, and equipment users are looking for a clean solution that won’t slash productivity. “We’re a conservative industry, and we’re in it to make a buck. Efficiency is how we do that,” says Dave Sbaffi, special projects manager for Granite Construction Inc., Watsonville, Calif.

The future of sustainable equipment may be found within tomorrow’s cars and trucks or somewhere in between. All mobile vehicles pose a similar problem to the environment: They have small combustion engines that crank out large amounts of power and torque. To get moving quickly, they burn high-output fuel that can be stored easily onboard. Light it up, and off it goes.

But emissions spew out the tailpipe into the atmosphere and find their way into the lungs of children and adults. Eventually, millions come down with asthma. Meanwhile, smog forms, and climate changes occur.

Hybrid Heroes

Global regulations that cut down nitrogen oxide and particle emissions are promising to save tens of thousands of lives a year. But they are not doing enough to curb global warming, scientists argue. One horse in the running is the hybrid powertrain. Whether it is an engine mated to an electric generator or a hydraulic transmission, several equipment producers are looking at hybrids to cut fuel consumption and minimize global warming.

Tudor Hampton/ENR
Kobelco�s Komiyama says hybrid excavator evaluations are set to wrap up later this year.

The most recent example surfaced at last month’s World of Concrete show in Las Vegas, where New Holland and Kobelco Construction Machinery Co.  showed a 7-ton diesel-electric excavator that they have been testing in Japan for several months. The plan is to begin reviewing production data by midyear to determine whether mass production of the “HE” excavator is feasible, says Masayuki Komiyama, manager of Kobelco’s hybrid group. If it works, the design could boost fuel economy by 40% and reduce greenhouse-gas emissions in equal numbers.

Kasmer’s hydristor could be another option. He has developed a hydraulic vane pump that draws power from a combustion engine and stores potential energy in accumulators mounted on the vehicle’s chassis. Doubling as the transmission, the hydristor can also recover energy from braking and, with a few more modifications, capture heat rejected from the engine to help recycle power in the system.

Kasmer built a working prototype—a John Deere riding lawn tractor—and displayed it at the Las Vegas CONEXPO equipment and IFPE fluid power show in March 2005. After unsuccessfully shopping the hydristor around to Detroit automakers, Kasmer is working on a retrofit kit for passenger cars that would retail for $3,000 and take mechanics just a few hours to install. Kasmer says his idea will be ready to roll with a few hundred thousand dollars of seed money and production space. “If I could change every last vehicle on the highways, I could see a 75% reduction in vehicle-generated greenhouse-gas emissions while doubling the fuel economy,” he says.

Construction equipment makers, such as Bobcat Co., reportedly are interested in the hydristor, as well, but are not ready to talk publicly about their research. Kasmer says his invention also has the potential to save energy for heating and cooling buildings by using hydristors mated to high-efficiency heat pumps.

Mack Trucks Inc.
Mack�s forthcoming hybrid diesel may burn 35% less fuel.

With hundreds of thousands of hybrid cars on the road, these cleaner powertrains are becoming a leading alternative fuel source. “Hybrids are for real,” says Guy Rini, director of advanced propulsion systems for Volvo Powertrain North America. The Hagerstown, Md.-based truck company, which supplies engines to Mack Trucks and Volvo Construction Equipment, is developing a diesel-electric hybrid powertrain that it wants to commercialize in 2009. Leif Johansson, CEO of Sweden-based Volvo Group, says climate change and volatility in global oil markets makes hybrid drive “an extremely attractive technology.”

Mack Trucks Inc.

So far, Volvo plans to use a clean-diesel engine connected to an “Integrated Starter Alternator Motor,” Rini says. It would charge 600-volt ultracapacitors, not batteries, to give work trucks—dumpers, concrete mixers and tractor haulers—a high-torque “push” at low speeds, where diesels typically are most inefficient, Rini says. Volvo also may use hydraulics to accomplish this.

The truck might not stop there. Volvo says it also plans to apply hybrid drive to off-road equipment. For these vehicles, engineers are exploring diesel-electric hybrids, diesel-hydraulic hybrids or a combination of both. “When you think about it, construction equipment has a lot more hydraulics on it,” Rini says. Hybrid machines could capture brake energy and energy from hydraulic oil while operators cycle through the implements.

Fuels of the Future
  Advantages Disadvantages
Biodiesel Biodegradable, May void engine warranty,
  high lubricity higher NOx output
Biomass Low emissions, Still in development
  high energy output  
Electricity Zero emissions Limited machines, mobility
Ethanol Low emissions Fuel economy, availability
Hydrogen Zero emissions Still in development
Hybrid Engines Fuel economy, Purchase price
  low emissions  
Natural Gas Low emissions, cost Limited machines
Propane Low emissions, cost Limited machines
Sources: Environmental Protection Agency, Dept. of Energy, ENR Equipment Research.

“It’s not as clear on the hybrid side if the exact system that we will use on construction trucks is what we will use on construction equipment,” Rini adds. But whatever the method may be, the manufacturer says it hopes to increase fuel economy by 30% for trucks and 50% for off-road equipment. That also would reduce the vehicles’ carbon footprints.

Various levels of hybrids already exist on cars. So-called “mild” hybrids, like the Kobelco and Volvo machines, supplement combustion engines with electric generators, but the two systems do not operate independently of each other. Higher levels—or “full” hybrids—such as several on the road today and the “plug-in” variety under development, can drive for greater distances without needing to use the engine, cutting both fuel use and emissions beyond mild hybrids. The stored energy “is just waiting like a cocked gun, ready to go,” says Kasmer.

Another potential source of low-carbon power is biofuels, which cut greenhouse-gas emissions and particulates. They are cleaner than traditional fuels and help reduce petroleum consumption.

Several cars and pickups employ flexible-fuel engines, which run on gasoline, ethanol or both. Soy-based biodiesel, a nontoxic fuel, is another alternative. Both produce fewer carbon emissions than straight-up fossil fuels but have downsides. “Biodiesel’s not the silver bullet,” says Albert Postema, president of Snohomish, Wash.-based Earthwise Excavation. “It’s more like silver buckshot.”

Tudor Hampton/ENR
Diesel engines are cleaning up but could get even cleaner, scientists say.

Big Switch

Postema switched to biodiesel in 2001 and has since used more than 78,000 gallons. The firm started fueling up with 100% biodiesel year-round but has cut back to 80% blends during the winter to avoid gelling. The firm’s program was risky because suppliers would not warranty engines running on more than a small percentage of biodiesel. Today, few engines are approved to run above 5%.

Scientists think that biofuels are a good start but not a long-term solution. Fuel economy suffers, and crop availability is a question. “I would rather not burn corn in my SUV,” says Sethi. “I would rather feed somebody with it.” Cellulosic fuels harvested from natural waste and biomass are more advantageous, he says. On the upside, “E85,” or 85% ethanol, reduces carbon emissions by 8% to 16% per mile, studies show. And 20% biodiesel, or “B20,” emits 10% to 15% fewer particulates into the air, according to Don Anair, a vehicle engineer for the Berkeley, Calif.-based Union of Concerned Scientists. Regulators are lukewarm on biodiesel, though, as it emits about 10% higher nitrogen oxides than petrodiesel.

Exhaust devices may expand its use. Particle filters are on new trucks and may soon come to off-road machines. Nitrogen-oxide catalysts are coming, too. “To make the largest impact, we advocate the use of after-treatment technologies in addition to biofuels,” says Anair.

Sbaffi says construction firms have “an absolute concern” for cleaning up but need alternatives that work. It may not be perfect, but Postema says his program is reaping unexpected rewards. “Our clientele has changed,” he says. “We charge a little bit more than the standard company, but people seek us out because of the environmental aspects…but boy, they pay their bills.”

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