The uninterruptible power-supply units can be as small as a bread box to nearly the size of two refrigerators. The units, which use one or more batteries to provide a brief supply of backup power, differ from generators, which create their own power.
One of the leading makers of the battery-powered boxes is West Kingston, R.I.-based American Power Conversion, whose 1999 sales topped $1.3 billion. Kristen Levy, a media-relations manager at APC, said it is probably too soon to gauge the impact of the power crunch on the company's bottom line. However, it has been good for building awareness of the types of products the company sells.
"The power anomalies in California are definitely increasing awareness about the instability of our power grid," Levy said.
Compton, Calif.-based Belkin Components, which makes uninterruptible power systems, said it has received urgent requests for more products from key California computer retailers, including Fry's Electronics and Micro Center.
"We're seeing a lot of retailers in the last week or so are actually kind of frantic," said Megan Daley, product manager for Belkin's power protection business.
Daley said Belkin is helping Fry's create a retail display to highlight the gear and is increasing its stocks to make sure it can meet retailers' needs.
"They're seeing increased demand, and they anticipate it will only get greater," Daley said.
Belkin also expects a jump in sales of surge suppressors, which can help protect against a spike in voltage when the power comes back after an outage.
Both generators and uniterruptible power boxes have been items of intense interest at State Electric Generator in Santa Cruz, Calif. Owner Stephanie Maridon said her business has seen an increase not only in inquiries, but also in service calls, because companies don't put their backup power systems to use very often.
"What we're hearing 
over and over is the frustration that this is even happening in the first place," Maridon said. "Everyone is used to having electricity."
Maridon said even her company found itself without power for 90 minutes Wednesday because its administrative office doesn't have a generator.
"It's going to," Maridon said. "It was really embarrassing."
Interest in fuel-powered generators, which provide longer-term backup, has also been on the rise.
Don Richter, owner of Stockton, Calif.-based Energy Systems, said business has been up for about a month as word of the looming crisis first hit the media.
"In the last couple of days, it's been crazy," Richter said. On Wednesday, he said, he was on a sales call at a gas station when the power there went out. Without power, the pumps didn't work.
Sold.
