Going five days without refrigeration means major losses for food businesses around the Bay Area, and the economic impacts of PG&E's power shutoffs are just starting to be understood.

"It doesn't take any heroic assumptions to think that a multi-day power outage impacting a million people means more than a billion dollars of economic impact," says Lawrence Berkeley National Laboratory researcher Peter Larsen. Speaking to the San Francisco Business Times, the energy expert says that it's too early to give any exact numbers, but the scale of PG&E's shutoffs this month is "unprecedented." "I don't know of an example at least in the U.S. where there's been advanced notice given to 500,000 to 1 million people that they will face a prolonged power disruption," Larsen says. "It's certainly a unique situation."

Larsen and his team, which studies energy resiliency and reliability and recently submitted a grant application to the U.S. Department of Energy to study these California shutoffs, will likely focus on the impacts on small- and medium-sized businesses.

Some owners of such businesses in Marin County spoke today with the SF Business Times, including Devon Yanko of M.H. Bread and Butter in San Anselmo. The bakery-cafe, which she opened with her husband Nathan Yanko, a Tartine alum, six years ago, has been forced to stay closed since they lost power on Saturday. Some things were able to go into a generator-powered freezer, but the business lost thousands of dollars in vegetables that went to waste, and 40 employees have had to go without pay for the last four days. "If I think about my own situation and multiply it over 35 counties, I can't imagine the economic impact this is having on people," Yanko said to the Business Times.

Larger operations like Safeway and the Nugget chain of supermarkets have been staying open and running on generator power, but those industrial generators can cost upwards of $25,000. A Safeway rep told the paper that most of its locations remained open, save for six that are in the Kincade Fire evacuation zone.

The Business Times also spoke with Corte Madera-based Stefano's Pizza, which ran its solar-powered pizza ovens and did bang-up business through the blackout because it was one of the only open restaurant in town. The only problem: They had to go cash-only because the credit-card machines didn't work.