In addition to being a biodiesel provider, the co-op wants to educate the public about biodiesel and renewable energy as well as encourage the use of biodiesel in the public and private sectors.

With negotiations in progress for the proposed Jones Island biodiesel refinery -- which would produce 24 million gallons of fuel a year and be the first of its kind in Milwaukee -- biofuel is assuming a stronger role in the plan for a greener city.

Milwaukee County Supervisor Marina Dimitrijevic recently pushed for the use of biofuel and green cars in her "green print" initiative, stating in her legislation to "direct the Director of Transportation and Public Works to purchase, when applicable, new cleaner technology fleet vehicles that use alternative fuels such as biofuels, hybrids and plug-in hybrids."

The City of Milwaukee already uses a biodiesel blend in its fleet and the co-op hopes for increased percentages as the fuel becomes more readily available.

Obsessed as we all are with fuel economy, it's no secret that diesel engines get better mileage -- about 30 percent higher -- than gasoline engines, clocking in between 40 and 50 miles per gallon. Co-op board member Kyle Capizzi has been using biodiesel in his Passat since 2004 and got similar mileage, but says that he noticed about a five percent hit when he started using B100, 100 percent biodiesel, last year.

Like anything, everyone agrees there is a flip side to using biodiesel. First, its use is restricted to diesel engines only. For a sedan in the U.S., that means buying a Volkswagen -- the Jetta, Passat, Golf and Beetle all make TDIs -- or a Mercedes Benz. Haas says General Motors has plans to introduce a diesel Saturn, Honda will have one by 2010 and that Peugeot is working on a diesel hybrid car.

Additionally, although the demand is increasing every year, it still hasn't reached the point where biodiesel prices are lower than that of petrolium gas or diesel. Currently, the Milwaukee biodiesel Co-op charges $3.20 per gallon for members, $3.68 for non-members. Haas says the non-member price includes the delivery fee and storage costs that are paid by the co-op.

"That number could go down. If we get a better deal, we all pay less."

And, like all cars, there are still emissions.

"There's no such thing as a perfect fuel," says Haas. "As great as biodiesel is, the one minor drawback is that is does have slightly higher -- about two percent -- nitrous oxide omissions, which contributes to smog. It's not that much higher than what comes from petrol diesel, but the good news is that it does not emit any soot or carcinogens into the air like other fuels. The next round of cars from Volkswagen and Mercedes Benz will have technology that traps the nitrous oxide and cleans it."

For the co-op's grand opening at Future Green this Saturday, July 28 is open to the public and features food, live music, an educational presentation by Capizzi and, of course, biofuel for the selling.