Not long ago, people who wanted to generate their own green energy at home had to content themselves with rooftop solar panels.
But new technologies -- and hefty government subsidies -- are now allowing homeowners to tap the wind, the Earth and other renewable sources in their own backyards.
Call it the green evolution.
The cost of heating and cooling with fossil fuels has nowhere to go but up, thanks to rising global demand and increased regulation of carbon emissions. Turning one's home into a clean mini-power plant is getting cheaper and easier all the time.
Here's a look at three technologies that some California residents are using now to cut utility costs while turning their homes into truly green houses.
Small wind
Californians driving along gusty interstates near such places as Palm Springs are accustomed to seeing commercial wind farms, where turbines as tall as buildings spin lazily against a blue sky.
These days, a modest but growing number of people are using a downsized version of that technology inside their own fence lines.
Roughly 10,500 small turbines were sold to homes, farms and businesses nationwide in 2008, according to the American Wind Energy Assn. Though 2009 figures aren't yet available, demand last year remained strong despite the recession, said Elizabeth Salerno, the association's director of data and analysis. A survey of small-turbine manufacturers has projected a thirtyfold increase in the U.S. market by 2013.
Locally, some of the growth comes from companies eager to lower their electricity costs. In Palmdale, for instance, city officials are allowing businesses to install wind turbines up to 60 feet high. Among them is Wal-Mart Stores Inc., which has a 17-turbine project planned for its Sam's Club store in Palmdale.
But interest is also surging among people such as Ernest Ramirez. He and his wife live in Oak Hills, an unincorporated, blustery section of western San Bernardino County dotted with spacious homes on multi-acre lots. The couple weren't looking to install a wind turbine. Their 3,250-square-foot home, which they purchased in 2003, just happened to come with one.
Ramirez can't imagine life without it now.
Perched on a slender tower about 80 feet high, the 10-kilowatt turbine has three 10-foot-long blades that whip often enough to keep his power bills from Southern California Edison at about $100 a month -- roughly a quarter of what he calculates he'd fork out otherwise.
Gusts are so fierce in this part of the Cajon Pass that they have been known to snap trees and jackknife semi-trucks. But Ramirez welcomes a bad hair day.
"When I get out of my car and it's blowing 35 mph and I have to stay inside the house, at least I know I'm saving money," said the 46-year-old grant writer. "Wind is such a precious resource."
Ramirez said he could count seven neighbors with their own wind turbines. Still, what works in windblown, rural San Bernardino County won't necessarily fit everywhere.
For a turbine to make economic sense, the AWEA said, a homeowner considering one should live in an area where 10-mph winds are frequent and be paying at least 10 cents a kilowatt-hour for electricity. Permitting is also a challenge in many communities; some neighbors consider the spinning contraptions ugly.
The technology certainly isn't cheap, running about $3,000 to $6,000 per kilowatt installed, or about $40,000 for a system large enough to power a typical home, according to the AWEA.
Subsidies are helping to soften some of that sticker shock. Homeowners can get a hefty rebate from the state of California -- up to $12,500. They're also eligible for a 30% investment tax credit from the federal government.
Geothermal
Solar panels and wind turbines are the rock stars of the renewable-energy world. But one of the most reliable performers is right under our feet.
Geothermal heat pumps harness the Earth's constant, natural heat to warm and cool a home, regardless of whether the sun is shining or the wind is blowing. Around since at least World War II, the technology consumes 25% to 50% less electricity than conventional systems, according to the U.S. Energy Department.
These devices gather ground heat through buried pipes that form a loop. During winter, an antifreeze-type fluid circulates through the loop, grabs heat from the soil and transfers it to the home, where it is circulated by a fan through the ductwork or vents. In summer, the process is reversed: The pump draws heat from the home's interior and dumps it back into the Earth.
Geothermal heat pumps are cousins of regular heat pumps, which extract heat from the outside air. The difference is that geothermal is more efficient because soil temperatures, even just a few feet underground, remain fairly stable year-round. Geothermal systems also have few moving parts, so they're quiet and durable. They can be adapted to provide a home's hot water.
