Your restaurant may be going green without your even knowing it, thanks to a mini-epidemic of grease rustling now underway. Discarded fryer oil stolen from you likely winds up as biofuel, but why not use it to generate free power for your business on site? The company that makes the necessary equipment promises annual energy savings of $10,000-$20,000 if you do.
Yellow grease—that’s the term for old fryer oil that’s been dewatered and filtered by a commercial renderer—was trading last week for $.475 per pound. That’s up from 11 cents a pound in late 2008. A gallon of oil weighs 7.6 pounds, so stealing used oil from restaurants has become is a lucrative proposition for the few people who have tanker trucks capable of handling this messy cargo.
It’s too much to pass up for some of them. Reuters reports that police in Omaha are looking for a thief who just ripped off 4,200 pounds of grease that originally came from a half-dozen QSR restaurants in nearby Lincoln, NE.
If you’re still paying someone to dispose of your discarded oil for you, it’s time to shop around for a better deal—i.e., one where the guy with the truck pays you when he hauls it away.
Since the price of yellow grease tends to rise when oil, diesel and gasoline prices increase, the grease-rustling problem may be with us for the foreseeable future. But you can avoid it, and perhaps even reduce your utility expenses, by recycling your restaurant’s used fryer oil in a Vegawatt generator.
Boylston, MA-based Owl Power Company manufactures this device. Here’s how company founder James Peret describes it: “The company's flagship product, Vegawatt™, is an automated, combined heat and power (CHP) system that utilizes waste vegetable oil as its feedstock.”
“A Vegawatt™ system contains more than just power generation equipment,” he adds. “It includes a turn-key waste vegetable oil (WVO) refinery, automatically transforming the darkest, nastiest used cooking oil into fuel appropriate for power generation.”
How exactly does it work?
“Our machine filters out all of the food crumbs, the beer-battered shrimp and onion rings and other gunk,” Peret said in a PBS interview. “It heats up to a point where the engine, which is a standard diesel engine or an industrial diesel engine, can utilize the oil.
“That diesel engine turns a generator head, which produces electricity, which is then fed back into the restaurant. The diesel engine also produces a lot of heat, and the restaurant can use that to produce hot water or for space heating.”
The Vegawatt unit is sized to serve the needs of a restaurant that has 3-5 deep fryers in its kitchen. It’s a supplemental power source, producing both electricity and heat, with the heat used to produce hot water. In practice, Vegawatt says, the unit would typically provide between 10 and 25 percent of a restaurant’s power needs. If you’re into saving the planet, the green benefits—reduced CO2 emissions, savings on fossil fuels—are significant. The dollar savings, as mentioned above, are touted as being in the $10,000-$20,000 range annually.
The generator unit, which is the size of a household refrigerator, is typically located outside a restaurant’s back door.
So does the Vegawatt work the same way as, say, the engine that powers Willie Nelson’s biofuel-powered tour bus? No, it’s different.
“It’s a quantum leap from that principle,” Peret says. “Biodiesel is a chemical conversion of vegetable oil into a transesterified product. We don’t undergo a chemical conversion. Instead of altering the chemistry of the fuel, we alter the engine so that it inherently burns the raw fuel.”
We don’t endorse the Vegawatt per se. But if you’re looking for a way to thwart your local grease rustlers, reduce your utility expenses and gain green street cred in one fell swoop, you may want to check it out.