Cars powered by vegetable oil are known as grease cars. See more pictures of alternative fuel vehicles.
Photo courtesy of California State Parks
While most car owners are filling up on fossil fuels once a week, and hybrid-car owners are happily filling up a couple of times a month, people who have converted their cars to grease cars are laughing all the way to the bank.
The eco-bank, that is. Grease cars run almost entirely on waste vegetable oil -- that's the stuff McDonald's (and pretty much every other restaurant) dumps out of its fryers daily. Grease-car owners only have to fill up on diesel about every couple of months.
And while a grease car gets about the same mileage as a regular diesel car and requires an up-front investment that can take a while to recoup, the car's emissions levels are a marked improvement over other types of vehicles, making it a phenomenal tool for reducing pollution. For one thing, there's no sulfur in vegetable oil like there is in diesel fuel; and sulfur emissions, which cause acid rain, have been associated with increased cancer risk, too. Grease cars also release up to one-third fewer heart-and-lung-damaging particulates into the atmosphere.
Other grease-car advantages target global warming. Greenhouse gas emissions can drop anywhere from 78 to 87 percent overall when you convert a diesel car to a grease car [source: Lloyd]. While they still emit nitrogen oxides and carbon monoxide, grease cars are carbon neutral: The vegetables grown to produce vegetable oil absorb more carbon dioxide than is emitted when a car burns that oil for energy.
So grease cars are a great choice for reducing your carbon footprint, but is it worth the effort? How hard is it to convert a diesel car into a grease car, and how much will it cost you?
In this article, we'll check out the grease-car process and find out if it's something just anybody can do. As it turns out, the initial conversion isn't such a big deal, but it's not the first step. The first step is to find yourself a good source of nasty fryer oil. You can't just drive up to a gas station and request fryer grease.
