Carl is the irrepressibly colourful owner and impresario of Carl's Corner, a truck stop 60 miles south of Dallas that has been drawing drivers for more than 20 years with its lavishly welcoming restaurant (house speciality: chicken-fried steak) and a variety of entertainments that have included a swimming pool and hot tub, the only alcohol-serving bar in an otherwise dry county, live country music and even, during the most down-and-dirty period of his entrepreneurial career, a strip joint.
Now he has a new attraction to offer: biodiesel fuel. The idea of powering trucks and cars with vegetable oils and animal fats may not be new in Europe, but in the United States - especially a United States uncomfortably aware of its dependence on Middle Eastern oil in the wake of the 11 September attacks - it is both a novelty and a cause of growing excitement.
Truckers who have tried it love it because it is cheaper than petroleum diesel, gives them better mileage and cleans out their engines. Farmers are excited because it offers them the prospect of a brand new market for their products - especially now that concern over mad cow disease threatens to restrict or cut off food-related uses of animal fats.
Cornelius loves it partly because it has given him the opportunity to push his business in a new direction, partly because he, too, sees it as a way of changing America and the world for the better, and partly because it has put him in business with his old friend, the legendary songwriter and country singer Willie Nelson. Nelson has been an energetic advocate for truckers, farmers and the hardscrabble American heartland for decades - he organised the Farm Aid concerts in the 1980s - and became a convert to biodiesel after his wife filled her Volkswagen with it at their holiday home in Hawaii a few years ago. Now he has lent his name and his considerable celebrity marketing skills to a whole new line of fuel called BioWillie.
And that is what truckers are now descending on Carl's Corner to buy. Since October, they have been able to fill up on B20 (20 per cent biodiesel to 80 per cent petroleum) beneath Carl's celebrated canopy adorned with six brightly painted polyurethane dancing frogs. Starting last weekend, when a raucous Independence Day weekend celebration of music and spit roasts launched a grand re-opening at Carl's Corner, the operation has expanded to include B40 (40 per cent biodiesel) and B95.
The four-lane fuel stop is being expanded to 10 lanes. The back of the property, where the pool and hot tub used to be, has been converted into a state-of-the-art, 800-seat theatre adorned with Texan horse motifs, old Hank Williams posters and framed sheet music pages from Nelson's most famous songs. Plans have already begun to build a dedicated biodiesel production facility a few hundred yards away.
"I am so doggone enthused about it right now, it makes my liver quiver," Cornelius said. "We don't have to be pioneers in this, because Europe's already ahead of us by a dozen years. All we've got to do is a little plagiarism ...
"We've got the resources in the United States ... we've got feedstock from animal fat, soybeans, sunflower seeds, the whole works. All we need is plants to process the biodiesel and get it going. If everybody's got biodiesel, we don't need awful wars. We can be totally independent from foreign oil."
Outside, in the sizzling heat of the Texas summer, truckers lined up for their own fix of BioWillie. Some had heard about it because they've been coming to Carl's Corner for years. Some heard Willie Nelson talking about it on his regular satellite radio programme - satellite radio being to truckers in the digital age what CB radio was a generation ago, a community-defining forum for what is otherwise a dauntingly lonely line of work.
Cynthy Cook, a compactly built driver from Nebraska who was hauling beef ribs across the country, said she had been interested in biodiesel for a while and found out about Carl's Corner on the internet. "You know how women are," she joked. "We're very nosey. I had to see what was going on." She, like her fellow truckers, could talk about her vehicle and her engine more intimately than some spouses can talk about their partners. So when it came to listing the advantages of biodiesel, she could reel them off with almost machine-gun speed. "It burns clean, it gives me better fuel mileage, it doesn't gel up in winter as easy and it helps the farmers out." Seeing me scribble down the list as fast as I could manage, she slowed down for a moment to summarise, with a laugh: "It's good shit."
Bernard Mugge, a ginger-bearded trucker from Indiana wearing a "Don't Mess With Texas" T-shirt - he loves the Lone Star State and stops off every chance he gets - said his interest was primarily economic, especially at a time of precipitous fuel price rises. "We don't make it out here," he said. "By the time I've made the truck payments and given the broker his cut and the company his cut and spent $20 (£11.50) to $30 a day just to eat, I'm getting maybe a third of what I make. I'm $11,000 in the hole and I just can't get out of the hole. So every little piece helps. If I can save on fuel, I'll do it."
The truckers say biodiesel gives them up to one mile per gallon of extra fuel efficiency. On big rigs that normally get little more than five miles to the gallon, the difference is huge - representing an annual saving on fuel costs that could run into the tens of thousands of dollars.
Biodiesel also offers one of the last best hopes to independent farmers, a dying breed in the American heartland because of the increasing dominance of vast agribusiness conglomerates and a federal government all too often indifferent to the plight of Americans in sparsely populated rural areas, representing little or no interest to them at election time.
In Nebraska and Iowa, two of the more progressive plains states, biodiesel production facilities are already up and running. This week, a group of small investors in impoverished western Kansas announced they were putting together about $40m to build a facility to produce both biodiesel and ethanol, another vegetable-based fuel. In Texas, various business entrepreneurs are believed to be working on building as many as eight facilities across the state.
Whether biodiesel can really fulfil the promise that Cornelius and others see in it remains an open question. Ethanol triggered a similar wave of excitement in the 1990s, but has provoked mixed feelings since - first because a number of studies showed that producing ethanol takes as much energy, if not more, than can be extracted from it afterwards; and secondly because it became apparent big agribusiness companies were taking advantage of the fad, and the federal subsidies that came with it, to dump their excess grain at the expense of small producers.
Biodiesel may be vulnerable to similar problems. A study published this week by researchers at Cornell and Berkeley universities suggested biodiesel, like ethanol, may require more energy to make than it produces. That finding, however, is contradicted by a 1998 study by the Environmental Protection Agency, which said that for every unit of energy going into biodiesel, 3.2 units are generated.
Mark Bernstein, an energy specialist and senior policy researcher with the Rand Corporation, said the truth was probably somewhere in the middle, not least because the technologies for extracting energy from raw materials were evolving all the time. "If you are using waste products - used oil and grease - then there's probably a net energy benefit you don't get if you have to grind the seeds from scratch," he said. "It also depends on the plant. Some plants are better for converting than others. The thing about biodiesel and ethanol is that they are good niche markets and we need those niche markets. But it's also clear that for a wide-scale use, the technology is not here yet."
Converting used oil and grease is an intriguing possibility. In a country where obesity rates are soaring, restaurants throw out an estimated 2.5 billion pounds of waste cooking oil every year. Could that be recycled profitably? Could it be that what is making Americans fat could also make them more fuel-efficient?
A group of students from the University of Virginia is putting that theory to the test with a cross-country road trip to Alaska in a souped-up, 20-year-old school bus. According to a piece in the Washington Post this week, the students have been stopping at restaurants and provoking all kinds of eyebrow-raising reactions by asking permission to siphon off their grease dumps. The slogan they have put on the side of the bus reads: "Powered by vegetable oil."
In many ways, biodiesel is to working-class heartland America what hybrid petrol-electric vehicles are to energy-conscious liberals in coastal cities and liberal university towns - a way of feeling better about the US's voracious appetite for fossil fuels and making their consumption a little more reasonable.
Cornelius, for one, has read his history and knows countries that do not look out for the big questions about their economies end up with depressions, political mayhem and families burning their furniture to stay warm in winter. "This is about changing the direction of the American economy," he said. And he has every intention of doing just that. As a shirt he has periodically sold in his convenience store, Carl's Potbellied Western Shirt, proclaims, he doesn't give up easily. His motto: "Cain't never could."
Biodiesel, manufactured in about 35 plants across the United States, is just the latest of numerous responses to the problem of energy supply. According to researchers such as Mark Bernstein of the Rand Corporation, the most promising avenues to pursue to reduce dependence on foreign oil are, first, mandating increased fuel efficiency in motor vehicles - something the Bush administration and Congress appear unwilling to countenance - and, second, developing hydrogen-based fuel systems.
This is on the Bush administration's radar, but is probably a decade away as a large-scale proposition. The city of Los Angeles possesses a few hydrogen fuel cell vehicles and operates a special high-pressure hydrogen fuel filling station, but this is only a pilot project for the moment.
California, a pioneer in alternative energies, had a big push a few years ago to install special recharging stations in public parking places. The problem with electric vehicles, at least for the moment, is that they do not go very far before they have to be recharged - no more than 100-150 miles.
Electric cars have been largely superseded by hybrid petrol-electric vehicles, which use fuel to fire up the engine and charge up the battery, which then takes over on downhill stretches or at lower speeds. Hybrids, pioneered by Toyota and Honda, have proved a huge hit on the US coasts. American manufacturers are rushing to put out their own hybrids, including four-wheel-drive versions.
In the heartland, the trend has been towards alternative fuels such as biodiesel and ethanol - firsty because they are more suited to trucks, and secondly because they can help small farmers otherwise struggling to stay in business. It is a cyclical arrangement: animal fats can be used to make biodiesel, while the left-over pulp from corn used to make ethanol can be put back into animal feedlots.
Ethanol has enjoyed federal subsidies for years, and biodiesel is beginning to as well. In Texas, biodiesel is exempt from state tax, so it can retail for about the same as traditional petroleum diesel - roughly $2.30 (£1.32) a gallon (3.8 litres).Reuse content