Build a Solar Home and Let the Sunshine In

Article Tools

Image Gallery

Print

E-mail

Comments

RSS

Simply orienting a conventional house to the south will cut annual energy bills by at least 10 percent, saving thousands of dollars over a home's lifetime. Add a long south-facing wall of windows and some thermal mass and you easily can tap sunshine's free energy to meet 50 percent to 70 percent of a home's heating requirements. Do your homework or hire a solar architect to create a rigorous passive-solar design and you can reduce your energy bills by 80 percent to 100 percent. Given the probability energy costs will increase steadily in the coming years, the long-term savings from a passive solar home could become very substantial, as we'll show in detail below.

UP-FRONT COSTS

According to Ron Judkoff, director of the Buildings and Thermal Systems Center at the National Renewable Energy Lab in Golden, Colorado, passive-solar features increase the cost of building a new home by anywhere from nothing to about 3 percent. (On a $200,000 home, for example, the maximum additional cost of incorporating passive solar heating might be only another $6,000.) Since many building codes now require much more energy-efficient windows, walls, ceilings and foundations than in the past, and you'll need a much smaller furnace or other backup heat source, passive solar frequently adds very little or nothing to the cost of a new home.

Judkoff bases his cost estimates in part on a series of case studies sponsored by NREL and the American Solar Energy Society, headquartered in Boulder, Colorado. (See "Comparing Passive Solar Savings".) Data on passive-solar homes were collected from a variety of locations across the United States. The study found the addition at cost of building a passive-solar home ranged from nothing to 3 percent, while the annual savings from passive-solar heating in the homes ranged from $220 in New Mexico to $2,255 in New Hampshire. Based on recent energy prices, a passive-solar home in a northern location could save you as much as $67,000 on heating and cooling costs over a 30-year period.

We all know energy prices are only going to rise. Some regions already have experienced sudden 100-percent spikes in natural gas prices. Major increases in natural gas and oil prices seem inevitable. (See "Running Out of Gas.") Without an inexpensive, reliable fuel source, millions of homeowners who rely on natural gas and oil may suffer enormous economic hardship. So let's take another look at those estimated cost savings from the NREL and ASES case studies. If we assume a 5 percent annual increase in energy costs, the potential 30-year savings from a passive solar home jump to $141,400, quite a return on a maximum investment of just 3 percent of your construction costs. If energy prices increase 10 percent per year, the estimated 30-year savings in cold climates could be more than $400,000.

RSS | Comments | E-mail | Print