SOUTHEAST TEXAS -
Filling up your tank at the gas station has become a weekly ritual for most Americans, but it's something restaurant owner Bill Carden doesn't have to do very often.
"I only fill up with diesel that I pay for about once a month," said Carden.
Which might sound odd, considering Carden drives a Ford F-250 Super Duty that only gets about 12 miles per gallon. That's because his truck can run on straight vegetable oil.
"Gas was approaching $4 a gallon back in 2007, and my son had actually done a little research on it and told me 'Dad you need to use your grease in your restaurant to power your truck'," Carden explained.
So he went to Houston and got his truck's engine converted by American Green Fuels, small company contracted out by Golden Fuel Systems, which claims to be the world leader in converting diesel engines to run on vegetable oil.
Carden said it took 3-4 days, and cost roughly $3,000... but for someone who drives 2,500 miles a month between his 4 Novrozsky's hamburger chains, he says the cost was well worth it.
"I'm probably saving, at a minimum, $500 a month," he said.
Conveniently enough, Carden gets the oil from the deep friers in his restaurants.
"I've got way more oil than I need. This is a 40 gallon tank, I fill up once a week on vegetable oil," he said.
Behind one of his restaurants is an area Carden affectionately calls his gas station. It's where he keeps dozens of 5 gallon jugs of vegetable oil together on shelves. He leaves them outside for 2-3 weeks, letting the hot sun separate the particulates.
After filtering the oil through a 2-micron sock filter, Carden then pours it in a special reservoir in the back of his truck. The oil then goes through a heat exchanger, and when it reaches 140 degrees Fahrenheit, Carden flips a switch by his steering wheel and the engine replaces the diesel with vegetable oil. He has to start every morning on diesel, and purge the engine of vegetable oil every night, but every mile in between his truck is powered by grease.
"The truck has 263,000 miles… 100,000 miles of that is on straight vegetable oil," he said.
Converting his truck wasn't without its drawbacks, however. Carden said that his truck's manufacturer told him converting it would probably ruin his fuel injectors. And sure enough, he had to replace his fuel injectors last January, which cost him close to $4,000.
But since he had his truck converted in 2007, he estimates he has saved close to $30,000 on fuel.
Bud Barber, the owner of American Green Fuels in Houston, says his company has converted as many as 300 trucks since 2006, for people from all over the United States and Canada. He says conversion was at its most popular in 2008.
