Ideas about what will power future cars and trucks are sprouting everywhere, from the labs of multinational corporations to the shops of backyard inventors.
Engineers at the EPA, whose main automotive job is to regulate the environmental performance of the car companies, are nurturing some concepts of their own at agency facilities in Ann Arbor, Mich.
Most promising, in their view, is a direct-injection engine that runs on alcohol fuel. Jeff Alson, a senior EPA engineer, said the engine is much more fuel-efficient than a diesel of comparable size and produces far fewer pollutants, two qualities that are top priorities of environmental regulators.
Engines designed for higher fuel economy generally have higher emissions, especially of oxides of nitrogen, a component of smog. Diesels have the inherent problem of producing small-particle pollution, or soot.
Alson, a senior staff engineer in the advanced technology division of EPA's Office of Transportation and Air Quality, said EPA's engine would cut oxides of nitrogen emissions by 50 percent to 80 percent or even more. At most engine loads it would be about 5 percent more efficient than a diesel.
He said EPA researchers used the clean-sheet-of-paper approach instead of trying to convert an existing engine.
They began with one-cylinder test engines. He conceded that some were failures, but said researchers made considerable progress with later designs. Their preferred concept engine is a four-cylinder powerplant that runs on methanol, which is made from natural gas.
Ultimately they would also expect it to run on ethanol. They also expect automakers to link it with an electric motor in a hybrid powertrain.
Despite the advantages of EPA's clean and efficient direct-injection engine, Alson said, 'Has any manufacturer stepped forward and said they want to start integrating it (into vehicles)? The answer so far is no.' Judging by concept cars the Big 3 showed last year, developed under the joint government-industry research program called Partnership for a New Generation of Vehicles, the industry is betting that small, efficient diesels teamed with electric motors in hybrid configurations will be the powertrains of the near future.
In effect they are gambling that pollution controls can be developed that will enable the diesels to meet the federal government's tougher clean air rules, which will be phased in from 2004 to 2009.
The Partnership for a New Generation of Vehicles was also the source of money used by the EPA to develop its concept engine.
Alson said the work is an appropriate use of taxpayer money even if the industry is headed in other directions at the moment.
Automakers prefer engines that use traditional fuels. They view alcohol as too costly to produce, lacking in energy density and incompatible with the existing gasoline and diesel distribution system.
Automakers and their suppliers have made it even tougher for new fuels by finding ways to cut pollution from internal combustion engines to levels once thought impossible. They appear committed to doing the same with diesels.
Whether they can reduce the emissions that foul the air and threaten health while boosting efficiency - and thereby also curbing greenhouse gases - is an unanswered question.
EPA's engine work represents 'a possible pathway (for the partnership) if conventional fuels don't work out,' Alson said.
He outlined EPA's engine efforts during a recent appearance before the National Academy of Sciences' panel studying possible revisions to federal fuel-economy standards.
A worthwhile program
John DeCicco, an independent transportation consultant and co-author of the Green Book, an annual environmental guide to new vehicles, said EPA's taxpayer-funded engine design work is beneficial even if other technology appears more promising. 'We have to hedge the options,' he said.
But he also said widespread use of alcohol fuels remains a long shot. 'I just don't see how to get from here to there,' he said.
DeCicco predicted the oil industry would find ways to make its products environmentally acceptable before it would give up the market to alcohol fuels.
Alson said alternative fuels have a large role, although obstacles remain. Their potential may not be realized until there are more oil-price shocks or new unrest in the Middle East, but they offer at least a partial answer to big questions about energy security, trade deficits and global warming, he said. 'Alcohol fuels still have a lot going for them.'
Harry Stoffer is a staff reporter in the Washington office of Automotive News