As gasoline prices continue to spike, many Americans -- Milwaukeeans included -- are finally accepting that petroleum is a destructive, finite resource. Yes, there's still a glut of gas-guzzling vehicles on the road, but more drivers are researching and buying rides that run on electricity or other alternative fuel sources.

Hybrid vehicles, like the Toyota Prius and Honda Civic Hybrid, are currently the most popular choices. Because both the engine and the electric motor connect to the wheels via the same transmission, hybrid vehicles use less gas and get around 50 miles to the gallon.

"The Prius is extremely popular right now. There's a six to eight week wait to get one," says Paul Renning, a sales representative at Andrew Toyota. "It's a fun and futuristic car."

But hybrids are part of both the solution and the problem. Because they still run on gasoline, the petroleum problem remains an issue. Hence, other forms of alternative fuels, like biodiesel, have garnered more attention recently.

Biodiesel is a vegetable-oil based fuel that runs in diesel vehicles. It's usually made from soy or canola oil, and can also be made from recycled deep fryer oil.

Russ Trzebiatowski, owner of four Culver's franchises in Wisconsin, uses recycled oil from his restaurants' deep fryers to power his VW Beetle. Almost a year and 13,000 miles later, he's happy with the results and says his vehicle runs more quietly now.

"It (also) smells like French fries a little bit," he adds.

Jessica Lawent of the Department of Natural Resources says this might sound like the perfect solution, especially considering the availability of fryer oil as a resource, but the logistics are problematic.

"Driving around to fast food restaurants every time you want to fuel up isn't practical," says Lawent, who claims it would be different if french fry oil could be purchased at regular gas stations.

Royse Myers is the president of Amco Energy Services, a Racine-based company that distributes soybean biodiesel to dozens of environmentally conscious drivers around the Midwest. Although Myers applauds anyone who uses a gasoline alternative, he believes biodiesel made from soybeans is the best.

"I don't fool around with the grease stuff," he says.

According to Royce, because the composition of fast food oil varies depending on what kind of food was fried in it, it's a less-dependable fuel source that affects day-to-day performance.

"Today it's onion rings in your gas tank, tomorrow it's french fries," he says.

But only diesel vehicles -- meaning Volkswagens and Mercedes -- can use biodiesel fuel, and because of this, Lawent believes hybrids, for now, are the preferred choice for passenger vehicles.

"Hybrids are more feasible. They have very low emissions, great mileage and are readily available at many car dealerships," she says.

But Lawent doesn't think the current hybrids are the ideal, rather a step in the right direction. However, she believes that in 2006, when the EPA enforces stricter regulations on diesel engines, hybrid diesels will be the best choice.

"Hybrid diesels will have better gas mileage and more power than the current hybrids out there," she says.

New EPA regulations will also, hopefully, change the public's perception of diesels. Because so many trucks on the road aren't taken care of, many people associate diesels with bad smells and plumes of black smoke.

"Diesels have the stigma of being dirty, which just isn't true if a vehicle is well-maintained," says Lawent.

Myers believes the fuel situation is urgent, and Americans need to make changes quickly, whether it means driving less or choosing an alternative form of fuel.

"Americans are married to the gas pump," says Myers. "It's extremely sad, because the end of gasoline's availability is coming, and when it does, all hell is going to break loose.

"Plus, using biodiesel is one of the most patriotic things you can do. You're supporting local farmers instead of buying it from Saudi Arabia."