Craig Baillie, a longtime bike commuter from Minneapolis, this year was looking for "the coolest bike on the planet." He turned to his buddy, Rob DeHoff, the owner of Varsity Bike and Transit, to help him find it.

The result? A bike with batteries and a propulsion system, capable of speeds as fast as 20 miles per hour.

In a summer of $4-a-gallon gasoline and few sweltering days, bike commuting has been gaining ground. Now come electric bicycles, for the commuter who doesn't want too much of a workout before work. Faster than bikes but slower than scooters, the bikes are an alternative to cars for commuters driving less than 20 miles. And though the numbers are still small, they've been popping up around the Twin Cities during what DeHoff called one of the best seasons he's ever seen for bikes.

Varsity began carrying a few lines of electric bikes three months ago. They're "right on the cusp of exploding," DeHoff said. In other cities, where the bikes have been around longer, "pretty much everyone is out of stock." Varsity has received calls from customers in California and Chicago, asking if they can ship the bicycles. (Yes, they can.)

And in a sign of how mainstream they're getting, electric bikes are being sold on websites of Target Corp. and Wal-Mart Stores Inc.

Target.com has carried two models of electric bicycles since July 30, according to Target spokeswoman Brandy Doyle. Three more models were being added this month, she said. As it does with many new products, the company is reviewing whether the bikes will be introduced to stores, Doyle said.

Wal-Mart began carrying a few models on its website last spring. "We certainly have seen a fast-growing interest, since they are easy to use and economical, and therefore they do not stay long in stores," spokeswoman Tara Stewart said.

"When the price of gas hit $4 a gallon, the spike in interest surged."

Erik's Bike and Board, a large chain of local bike shops, does not stock the electric versions and has no plans to.

"Only human-powered bikes," a sales associate at the Eden Prairie location said.

David Olson, president of Erik's Bike and Board, said they carried electric bikes about five years ago, but discontinued them because the technology was inconsistent among lines. The weight of the bikes was also a drawback for urban bikers, he said, because many of them have to carry their bikes up and down flights of stairs.

Besides for commuters, Olson said he's seen the bikes used by RV travelers who need some form of local transportation once they park their big recreational vehicles on trips.

Varsity staff have all been riding the different models of electric bikes -- they stock six brands and 12 models -- to familiarize themselves with them and decide which ones to keep.

"We won't sell a bike we don't like," DeHoff said.

Federal law mandates that electric bikes have pedaling capability and that speeds top out at 20 mph. Otherwise, the device is a scooter, DeHoff said.

Although Varsity has done service on electric bikes for a few years now, it's able to do much more in the newly expanded space, 10-year employee Jameson McGuine said.

"It's been a little bit of research," he said of learning how to service the bikes and work them. "We had to pretty much create an electrical department."

McGuine said he knows that most college students can't afford a bike that costs about $2,000, but "it's just one extra added service for people who do have the money and do want to make that jump." And obviously it means big fuel savings.

Baillie said he loves the electric bike DeHoff chose for him. Baillie, who owns a small website design business in southeast Minneapolis, said it used to take him about 20 minutes to bike downtown to where his clients are based.

"I was often pretty sweaty to do it at that speed," he said, "and occasionally had damage to my clothes because of the chain."

These days, Baillie can zip into town in about 10 minutes without breaking a sweat or ruining his clothes.

"I'm not interested in sweating off 5 pounds on my way to a meeting," he said. "I'm interested in getting to my meeting in a predictable amount of time."

Emma L. Carew • 612-673-7405