A Diesel-Powered Intrusion
To hard-core environmentalists, it was as though John Muir had suggested clear-cutting Sequoia National Forest.
“We have confidence that, given past history, the auto industry will rise to the challenge and we will have light-duty diesel in California.” This was Alan Lloyd, longtime electric-car champion and president of the California Air Resources Board, recently declaring in a newspaper that diesel-powered cars, sport utility vehicles and light trucks will become part of the solution, not the problem, in California’s effort to clean the air.
Behind his heresy is the need to reduce greenhouse-gas emissions under the state’s global-warming abatement law. Lloyd said he was impressed by the U.S. Environmental Protection Agency’s test results on the European-marketed Toyota Avensis, a diesel passenger car, and the success of diesels in Europe. He also said that he had been pushed by Gov. Gray Davis, who may want to avoid another legal challenge by motor industry lawyers like those who recently won a rollback of the Air Resources Board’s electric-car mandate.
Jerry Martin, an Air Resources Board spokesman, said Lloyd’s statement “wasn’t anything really new. We’ve never ruled out any technology that could give us cleaner air.” But what did appear new was the board chief’s claim that long-reviled diesel was the technology that could do it.
Lloyd and his board have led the nation in fighting for a reduction of diesel emissions. Major studies by USC, UCLA and other top institutions have connected diesel particulate emissions with respiratory ailments among children and adults in neighborhoods adjacent to crowded freeways, making diesel pollution an environmental-justice issue. And it’s one reason why the federal EPA, within five years, will require -- via innovative technology and low-sulfur fuels -- that new diesels be 97% cleaner than those of today.
So strong has the air board’s anti-diesel sentiment been that some clean-air advocates wonder what’s with Lloyd. According to one skeptical environmentalist, “Increasing the use of diesel to clean up the air is like taking up smoking to lose weight.” Or, as automotive historian David Kirsch puts it, “You can have cleaner diesel. But there’s no such thing as clean diesel.” Even the European-market diesels Lloyd cited as examples of how good diesels can be do not meet the impending EPA rules.
Yet, the fact is, most diesels pump out less carbon-dioxide greenhouse gas than gasoline engines of the same power range, leading some to wonder whether the air board might be inclined to seek more greenhouse reduction in return for an increase of other diesel pollutants.
But Lloyd has vowed to make no compromise in emission standards while seeking the diesel-power option, particularly in popular (if CO2-prone) SUVs, as well as light trucks and cars. It’s not yet clear exactly how that can be done, though. Carbon dioxide, the basic combustion byproduct, causes global warming. The less fuel an engine burns, the less CO2 it pumps out. State law requires auto makers to reduce CO2 emissions by 2009, and Lloyd says the greater use of diesel could make this happen.
But diesels also emit nitrogen oxide (NOx) gases and sooty flakes called particulate matter. The former make smog; the latter are a factor in respiratory disease. And the particle traps and NOx catalysts needed to meet the 2007-10 federal clean-air deadlines are still in development and of uncertain durability. What’s more, most of these devices are intended for 18-wheeler trucks, not cars. Nor even the bulky, best-selling CO2-belching SUVs the new law appears to target.
“It’s a dead end,” said Dan Lashof of the Natural Resources Defense Council in Washington. “We’re all for any technology that makes for cleaner air,” he added, but he said other technologies -- particularly gas-electric hybrid cars like Toyota’s Prius, which has sold 100,000 worldwide -- offer both low CO2 and low emissions of other pollutants, plus mileage as good as a diesel. Other engineering innovations can both lower conventional gas-engine cars’ CO2 emissions and raise mileage to diesel levels, according to veteran auto engineer and consultant Vahe Kludjian. These include high-voltage electric systems that would power what are now engine-driven accessories, as well as direct fuel-injection systems.
Diesels make up 30% of the European car market, and overseas manufacturers are developing the technology to the max: One Opel-Fiat two-seater diesel show car reportedly gets 94 miles per gallon.
But U.S. skeptics like Kludjian and Lashof say that diesels cost more than equivalent gas-engine cars, and their greatest appeal is that diesel fuel is about 25% cheaper than regular gas in Europe. (In California, diesel often costs more than regular.) What’s more, it has been a long time since mileage was a strong selling point to Americans, who may still be averse to going diesel because of the foul reputation that U.S.-built diesel cars acquired in the late 1970s.
Besides, Euro-diesels don’t have the high-tech add-ons needed to meet coming federal EPA and California regulations -- and it’s uncertain how well they would run if they did.
The official EPA/Society of Automotive Engineers test report said that the Avensis, when burning an ultra-low-sulfur fuel not available commercially, met EPA’s intermediate 2004 diesel-emission requirements. But it added that the test was too brief to confirm the durability of the car’s innovative duplex pollution-control system. Toyota spokeswoman Holly Ferris said: “That vehicle has nothing to do with the North American market.”
In any case, Toyota has a much stronger clean-air commitment to its Prius and other hybrids, including a full-size sedan now marketed in Japan. Nissan, Toyota’s major competitor, has also announced a hybrid program. Manufacturers and environmentalists mostly agree that this looks like the way to go. As Lashof put it, “Because of the hybrid’s electric component, it’s the link to the fuel-cell future of the automobile.”
Lloyd’s dark-horse diesel choice could be the loser in this critical race for clean air.
