FORT WORTH — Outside Mike Renner’s two-story home in Azle, a sleek white turbine whirs in the wind.
The 10,000-watt wind turbine sits atop a 100-foot tower Renner built himself. Solar panels cover his roof, producing 8,000 watts of power.
In the sticky months of August and September, Renner’s thermostat never budges higher than 72 degrees. Yet he pays only $15 a month for electricity, a utility service charge, which he uses only as a backup plan.
“A lot of people get sticker shock from their electric bill every September,” Renner said. “We don’t.”
Driven by the desire to create healthier living environments and be more water and energy efficient, green home building is steadily rising, according to a report by McGraw-Hill Construction. The report says that 22 to 25 percent of new home construction will be green in 2013 and is expected to rise to between 29 and 38 percent by 2016.
But a small number of homeowners go much further that having energy efficient toilets and high-performance windows; they produce enough power from renewable energy sources to live entirely off the grid — or at least tread lightly on it. Homeowners tout the long-term cost savings and smaller carbon footprint of off-the-grid living.
Few statistics exist on the number of homeowners who shun commercial power. Richard Perez, publisher of Home Power Magazine, estimated in 2006 that roughly 180,000 families in the United States live off the grid and that the number grows by about one-third every year.
For Renner, the journey to go off the grid began in 1986 when he had an epiphany of sorts.
“I thought, ‘Why should I pay to rent electricity from a utility company when I can harvest plenty of energy straight from the sun?’” he said. “It made no sense.”
On five acres outside of Azle, Renner built a two-story, 2,300-square-foot house, complete with solar panels and the wind turbine, a large rainwater capture system, gardens and two greenhouses. A self-built trailer has 2,250 watts of solar panels and provides power at area concerts and other outdoor events.
To do most of the work, Renner studied articles from Home Power Magazine and attended meetings at the annual Renewable Energy Roundup in Fredericksburg, also relying on a professional background in electronics.
Renner, who offers talks and lessons on renewable energy, urges others to view energy efficiency as a long-term investment. “Renewable energy is free and it does not pollute,” Renner said. “Our planet is in crisis. It has a fever, and it’s going to escalate if we don’t do something.”
Buildings — including residential — accounted for 39 percent of all U.S. energy consumption in 2005, according to a report by the Environmental Protection Agency. And building occupants use 13 percent of the water consumed in the U.S. each day, according to the report.
Off-the-grid living is not cheap, though.
In Renner’s case, he estimates it will take 17 years to earn back his investment, and he’s OK with that.
“People will spend money on a luxury car that goes down in value the minute they drive off the lot,” Renner said. “This will eventually pay for itself.”
In 2007 and 2008, Ron Hein spent $26,000 to install 3 kilowatts of solar panels on his home in Fort Worth’s Cultural District.
The system reduced his electricity costs by about 45 percent, but recouping the cost of the panels will take about 15 years.
Hein also outfitted his home with thick windows, spray foam insulation and a geothermal heat pump. He and his wife, Kim, cook with a solar cooker instead of a conventional oven and hang clothes to dry in their back yard.
Even with those changes, Hein’s home does not supply all of its power, and he relies on the electric grid for the rest. Someday, he said, they might try to produce all of their power.
Hein said he has learned one important lesson.
“The whole family has to be committed. You can’t have one person doing his part if the others don’t care,” Hein said. “That’s just painful, and it won’t work in the end.”