03/16/2012 04:44 pm ET

Stolen Kitchen Grease: Bay Area Thieves Target Alternative Fuel

The newest item on Bay Area thieves' wish list? restaurant grease, the easiest thing to convert into biodiesel fuel.

As eco-friendly cars reach a new high demand, so does the need for "yellow grease," or leftover cooking oil.

“There is a black market for yellow grease now,” Andrew Panell of Dogpatch Biofuels told CBS San Francisco. “Independent people will steal it here and there and use it for their own vehicles, diesels converted to burn vegetable oil.”

Within the last two years, grease prices have skyrocketed from six cents a barrel to 50 cents, making this black market network larger and more complicated than just individuals trying to beat gas prices.

The San Francisco Chronicle reported Friday that professional grease haulers have emerged as of late. Thieves often hit more than one restaurant a night, carting off tens of gallons in the back of a van. Although only a truck, a pump, and bolt cutters are technically necessary for the operation, some thieves go to great lengths to get the prize using crowbars, hammers and even blowtorches.

Since many of these thieves are actually licensed to collect grease, it has become extremely difficult to determine what has been stolen and to punish the guilty.

"It's very difficult to get district attorneys to take it seriously," Douglas Hepper, head of the California state agency that regulates the disposal of grease, told the Oakland Tribune. "They're busy with murders and meth labs, and they have limited budgets themselves, so they have to set priorities.”

Thieves can siphon thousands of dollars by emptying the large containers stored in the back of restaurants, instituted as a measure against restaurants dumping the greasy waste down the drain and clogging the sewers. Overall, the continuous thefts have caused almost a million dollars in losses each year for the industries that collect and process the grease.

"It's liquid gold," Daniel Rugg told SFGate. As director of engineering at the Four Seasons hotel in East Palo Alto, he has frequently had to chase away thieves from the restaurant's 500-gallon grease tank.

While the California Department of Food and Agriculture can charge up to $1,000 for each violation, many thieves make much more than that in a week’s worth of stolen grease.