KENLY - It seems easy enough -- park the rig for the night, grab an extension cord and plug in to an outlet to power the heater or a TV.

But most truckers have to keep the engine going all night long, which means higher fuel costs and emissions. They rely on the truck's engines to power their computers, televisions, heaters and air-conditioners.

Last month, Big Boys Truck Stop on Interstate 95 at Bagley Road became only the third truck stop in the state to offer an overnight plug-in option.

The family-owned truck stop, which has more than 200 parking spaces, now has 24 outlets for truckers and charges $1 per hour for their use. That's much cheaper than the gallon of diesel per hour a truck burns while idling. Environmentally, plugging in saves 22.2 pounds of carbon dioxide emissions per hour, which Anne Tazewell of the N.C. Solar Center equates to planting a tree.

"The emissions reductions are really impressive," Tazewell said.

Big Boys manager Wendi Powell said the outlets wouldn't likely generate a lot of profit. But Big Boys wanted to differentiate itself from bigger competitors, she said.

"We have to move toward what the future trends might be," Powell said. "This is the beginning of trying to build a corridor" of electrification stations.

Truck-stop electrification has been a long haul for clean-air advocates. Electricity is a bargain over diesel, but most truckers opt for burning fuel rather than running their gadgets and heaters with an extension cord snaking out the window.

Other challenges remain. The biggest might be that some trucking companies have already gone to the expense of fitting their trucks with auxiliary power units. APUs are essentially diesel-powered generators, but they consume less fuel than truck engines.

Anthony Stallings, who drives for Bill Patterson Co., said his company is considering adding APUs. While refueling at Big Boys last week, he said the electrification stations might not be practical enough for his needs. "With an APU you can park anywhere," he explained.

It took the N.C. Solar Center, which helped finance the Big Boys project, nearly three years to find a truck stop willing to put in a basic electrification station for about $180,000.

Nationwide, there are only 139 truck stop electrification projects, according to the U.S. Department of Energy. There are about 2,000 full-service truck stops in the country.

For years, one stumbling block to electrification was that trucks couldn't easily use outside electricity. Only in the past few years have manufacturers offered factory-installed wiring and equipment to allow drivers to use electricity rather than diesel. Companies can also retrofit their trucks adding an electrical plug and air-conditioning system for about $3,000. Also, some electrification stations rent heating and air-conditioning equipment.

Joe Licari is director of East Coast operations for ShorePower, which installed the stations at Big Boys. He expects trucks to follow RVs in moving toward electric power. His company is using Big Boys as a pilot site for its efforts to install the stations throughout the country