Before power lines, people had no choice. They used lanterns, lit fires for warmth and packed away winter ice against hot summers.

But now, a growing number of Americans are shunning power lines, choosing to live "off the grid," without commercial power -- and still enjoying their computers and large-screen televisions.

In the 250-home Oregon community of Three Rivers, everyone gets most of their power from solar panels on their rooftops or on nearby structures positioned to more efficiently capture the sun.

The solar power easily handles their lights, microwave ovens, refrigerator-freezers and other needs. Some supplement the solar power with windmill-generated energy.

"Ninety percent of the people here, if (outside) power were offered to them, they'd turn it down," said Gary Sweet, who moved to the high desert community a couple of years ago.

Off-the-grid living is edging into the American mainstream. About 180,000 homes, mostly in the West, operate on it, though the power industry has not yet felt the shift. "I can't imagine any appreciable impact on the system" in the short term, said Jim Owen of the Edison Energy Institute in Washington, D.C.

But the number of people going off the grid increases by about a third each year, said Richard Perez, who publishes Home Power magazine, dedicated to the topic, and Lori Ryker, who has written two books on the subject.

Much of the growth is in California, though off-the-grid living is also growing in Texas, New Jersey and Wisconsin.

The change is popular in the West because people are moving into remote areas beyond the reach of commercial power. Others point to environmental conscientiousness and the Westerner's traditional independent streak.

Residents in upscale, gated, Three Rivers easily could afford the $300,000 the power company said it would cost to extend its lines three miles (4.8 kilometers) or so to their property 10 years ago.

But they have decided to stay off the grid.

"With power lines come streetlights, and there go your stars at night," Sweet said. "And there are no power outages here."

Off-the-grid residents have a guaranteed power supply at a time when the emphasis on "clean" energy is on the rise. Solar energy uses no resources to speak of, emits no pollution and is immune to energy price hikes.

Still, living off the grid is not cheap.

High demand for solar panels and improved technology has kept the price up, and Three Rivers homeowners say an advanced solar energy system can cost $25,000 (euro18,496) for the panels, batteries, inverter and other equipment. The federal government and most states offer tax credits.

Savings over commercial power costs depend on the investment and durability of the system and local energy prices.

Silent and simple, with no moving parts, solar panels convert sunlight to DC energy, send it through inverters that change it to AC and store it in batteries that can supply the 110-volt needs of a home for three or four days. The panels last about 25 years, the banks of batteries about 10. If the batteries run low during cloudy periods, generators recharge them.

"We went from Feb. 11 to Sept. 15 (in 2006) and the generator never ran. All solar," Sweet said.

Residents with wells need generators for their pumps, and propane powers high-demand appliances such as stoves.

Beyond that, the sun does the job.

From 80 to 85 percent of off-the-grid homes rely on solar power because it is the most available and reliable in most areas, said resident Richard Perez. And with no moving parts, it is easier to maintain.

Many rural and urban homeowners are using partial alternative systems -- adding solar panels as a supplement while staying on the commercial power grid. If they produce more power than they use, they can sell it back to the power companies, which usually are required to buy it.

Homeowners are not alone in going off the grid.

The Los Angeles Community College District hopes to start moving its nine campuses, plus two in development, onto solar power beginning next year.

Larry Eisenberg, executive director for facilities planning, said that with credits and other incentives through private contractors, systems will cost between $900,000 (euro665,877) and $1.8 million (euro1.3 million) each and that energy savings should recover capital costs in about two years.

"Our goal is to save $9 million (euro6.6 million) a year," he said. "We want to show people this can work. We've been chatting with a lot of people. If we can do it, anyone else can do it too."