They thought they were doing it right: When Stephen and Rebekah Hren went off the grid, back in 2003, building their own solar-powered adobe house, it seemed like the biggest favor they could do a warming globe. But the house was in the woods 30 miles north of Durham. That meant that Stephen, a carpenter, and Rebekah, an electrician specializing in solar energy, were each burning up to three hours a day of gasoline to earn their livings.
"Even though the house was sustainable, we were not living sustainably at all," says Rebekah, by phone from Durham. "It was not a very good example to be setting."
Their solution blended the past and the future. They bought a 1930s duplex in central Durham, made it as energy-efficient as possible, then retrofitted it to meet their dialed-down needs entirely with renewable energy. And they wrote about it in their new book, The Carbon-Free Home: 36 Remodeling Projects to Help Kick the Fossil-Fuel Habit, from sustainability specialists Chelsea Green Publishing.
The 320-page book categorizes the projects by skill level, time and cost required for completion, and energy saved. Illustrated with photos and diagrams, it shows how, on a budget, they stopped contributing to global warming and resource depletion, and also saved money.
The Hrens, both 33, did 30 of the projects at the two-story, 1,500-square-foot wood-frame place they bought for $150,000. The efficiency quest began with easy steps like turning off and unplugging unneeded appliances, switching to compact-fluorescent light bulbs and line-drying clothes; then came blown-in insulation and storm windows. They now use about 150 kilowatts of electricity a month -- roughly 19 percent of the national household average.
The retrofitting was a little more complex. Their refrigerator, lights, computer and stereo run off a small photovoltaic array they installed. The sun also powers the pump that circulates water to the roof for their "passive solar" water heater. The house is heated by wood stove, and with circulated air from a built-in greenhouse; cooling includes stuff like simply closing the blinds in the afternoon. "We do a lot of daily management of sunlight," says Rebekah Hren.
Meanwhile, the couple's most outré strategies involve cooking. Tools include the woodstove, a solar oven (a crockpot-style outdoor device) and an ethanol stove that burns plant-based fuel. Baking is problematic. "We haven't really figured out the oven part," Rebekah Hren admits. What to eat is less troublesome: They're gardening enthusiasts, and Stephen has a sideline in edible landscaping (fruit trees, etc.).
Carbon-Free Home has projects even renters can do, says the Hrens. And denizens of relatively cloudy Pittsburgh shouldn't fear all the reliance on solar, says Rebekah: "Germany is way ahead of us" on solar, even though that Northern European country gets less sun than most U.S. locales.
Meanwhile, the Hrens still grapple with fossil-fueled transportation: They recently unloaded their car, a Mercedes converted to run on waste vegetable oil, and are exploring new ways to get around.
"It's going to be extremely hard," says Rebekah Hren.
"It'll be a good motivation to get us to learn all the bus routes," says her husband.
Stephen Hren discusses and signs The Carbon-Free Home 2 p.m. Sun., June 15. Joseph-Beth Booksellers, 2705 E. Carson St., South Side. Free.