Diametrically opposite today’s gas-guzzling SUVs is a passenger car that gets 50 miles to the gallon. It is not a hybrid gas-electric like the Toyota Prius, it is not a subminiature car like DaimlerChrysler’s Smart, it runs on neither natural gas nor vegetable oil. Based on modern refinements of a century-old technology (invented 1893), this car — and this technology — are both cheap and reliable. It uses a widely available fuel which costs, for the average gallon, 17 cents less than regular gasoline. And, based on the narrow-mindedness of well-meaning politicians, this particular car — the Volkswagen Golf TDI — is illegal for sale or registration in California, New York, Massachusetts and Vermont, or nearly 40 percent of the U.S. passenger market. Turbodiesel (TD) engines — the magic behind the Golf’s miserly fuel economy — fail to meet California emissions requirements that took effect this year.

If this sounds like a Volkswagen commercial, it is only because Volkswagen is currently the sole vendor of new diesel passenger cars in the U.S. (though, after a long hiatus, Mercedes re-enters the market this fall). Though this might seem as if TD vehicles are the purview of trendy European automakers, they are actually far from foreign to Detroit. Internationally acclaimed models include Ford’s Focus (fashionable amongst young Italians), which gets a whopping 67 miles per gallon (about a 30 percent increase over the gasoline model); while my Chrysler Minivan guzzles about 17 mpg, drivers across Europe enjoy a 32 mpg TD version unavailable in the United States. Dozens of other models from Ford and Chrysler, as well as General Motors through its Opel and Vauxhall brands (rebranded Chevys), round out the Big Three’s TD offerings. Virtually every global automaker — Honda, Toyota, Daimler, Volvo (now Ford), Jaguar (also Ford), BMW, Saab (now GM), Fiat, and others — offer TD engines as normal options across their entire passenger product line. In fact, turbodiesel production has become a competitive necessity: TD passenger cars now comprise 40 percent of the European market.

California’s problems with diesel vehicles are not entirely unjustified. The LEV II (Low Emissions Vehicle II) standard that took effect for model year 2004 holds all cars and light trucks — diesel, gasoline, natural gas, or otherwise — to the same emissions requirements. Turbodiesel vehicles release higher levels (than gasoline) of particulate matter, nitrogen oxides, and sulfur into the atmosphere. However, since they are more efficient, TD engines release significantly less carbon dioxide per mile — which (along with water vapor) is the primary agent of global warming. For example, one of Ford’s TD Focus models releases 143 grams/kilometer of carbon dioxide, compared to 183 for a similarly performing gasoline model (21 percent better carbon emissions). Honda, which has recently taken out more than 100 British patents on environmentally sound and customer-friendly turbodiesel technology, produces a diesel-powered Accord that offers a 27 percent reduction in per-mile carbon emissions.

Advances in technology combined with legal changes in acceptable kinds of diesel fuel have made diesel cleaner than ever. New EPA regulations mandate a 95 percent reduction in the sulfur content of diesel fuel by 2006 (from 300 to 15 parts per million; Europe has a 50 ppm standard), which in turn will allow sulfur-intolerant particulate filters currently used in overseas.

What I am not advocating is open season on emissions standards, or the creation of loopholes for gas-guzzling SUVs and “light trucks” to get around emissions standards. Instead, I propose that — for the sake of decreased greenhouse emissions and fuel economy — California relax its emissions requirements for diesel passenger vehicles under 3 tons (virtually all sedans, coupes, and station wagons). They might consider temporarily adopting E.U. emissions standards for diesel vehicles, which are set to become gradually more stringent. A little more than half of California’s diesel-related pollution comes from farm vehicles and machinery, and most of the rest comes from trucks. It would behoove California to force even stricter standards upon these two pollutant sources, while re-legalizing diesel passenger cars; they produce such a tiny fraction of diesel-relation pollution that marginalizing them at the expense of fuel economy and overall greenhouse emissions seems somewhat pointless.

At the same time, American consumers ought to radically rethink their conceptions of diesel-fueled vehicles. Turbodiesel engines — which have been perfected only in the last decade or so — represent a dramatic improvement over the loud, smoky clunkers of yesteryear. In spite of their higher emissions, TD engines still pass muster in 45 states; absolutely no foul-smelling fumes at traffic lights. New diesel cars are quieter than ever. There are other advantages as well, such as highly reliable long-life engines and fewer high-wear components (no spark plugs, for example) — even without the increase in fuel economy, turbodiesel vehicles offer a significantly lower total cost of ownership.

Unlike other fuel-savings technologies — such as gas-electric hybrids — TD engines actually offer performance advantages over their gasoline cousins, with higher towing capacity and substantially better acceleration in the 30-60 mph range. Finally, there is the issue of fuel economy. Assuming you own a Ford Focus, pay national average gas prices, and drive it 10,000 miles/year, you would save about $200 per year. On the other hand, you were to drive a seven passenger minivan — like my Chrysler — fuel savings for the diesel model would be closer to $500.

While diesel vehicles are certainly not the long-term answer to our environmental problems, their utility to both consumers and environmental advocates should not be discounted. Particularly as the technology continues to improve, it would make sense for consumers to consider turbodiesel vehicles, and for states like California to consider allowing their citizens to purchase them. Perhaps as both diesel and hybrid technologies develop, and if buyers accept them as viable alternatives to gasoline, automakers would consider combining the two technologies. An ultra-low emission turbodiesel hybrid with 90 mpg fuel efficiency would be a wonderful solution.

L. David Peters is a senior in Davenport College.