Kohler Power Systems, which makes "standby" generators to be permanently installed, says it had record sales last year. Generac Power Systems, which has the lion's share of the generator market, said its revenue doubled between 2010 and 2012.

"Certainly in the wake of the storms that you folks have had in the Northeast over the past year, we've seen a great surge in interest for backup power systems of all kinds," said Art Aiello, a spokesman for the Wisconsin-based Generac.

Generac makes portable and permanently installed generators. Its portables generally sell for under $1,500, while the most popular of its standby brands — which automatically switch on when the power goes off — retails for about $4,600.

Stuart Merenbloom, a retired teacher who lives in Catonsville, said he can attest to the wild demand for portable generators after Sandy hit.

"Even a month after the storm — even online, like places in the Midwest — they were out," he said.

Merenbloom is seriously thinking about buying one, given that the derecho and Sandy each cut power to his home for four days, but he has reservations. The thought of storing gas in the shed to power a portable generator worries his wife. He looked into getting a standby generator instead, but a contractor told him the backyards in his neighborhood of rowhouses aren't big enough.

Merenbloom's not planning to move, so his storm-prep options strike him as fairly limited.

"You can only do so much," he said.

And you don't want your preparations to backfire, either. Ed McDonough, spokesman for the Maryland Emergency Management Agency, said portable-generator owners must be very careful to avoid carbon-monoxide poisoning by running them outside the home — and away from areas where the fumes could get back in.

"Sometimes people think a garage is OK, and it's not," he said. "And sometimes people think a porch is OK, and it's not."

McDonough also suggests that homeowners consider their yard if they want to be more storm-conscious. Falling trees and tree limbs are a major cause of power outages during storms, and they can pose a hazard to homes, too.

Then there are the backup sump pumps, battery- or water-powered. Laurel Peltier, a North Baltimore resident, had the latter installed after it occurred to her during a big storm that she'd be waterlogged if the electricity went out.

She encouraged Sorensen, her friend and neighbor, to follow suit. She figures most people don't think of a backup until the water's gushing in.

"Your power goes off a lot more now, and it's not for a couple hours, it's for a few days," Peltier said. "You just have to think differently."

jhopkins@baltsun.com

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