The sunny South is not exactly stampeding toward solar power. But spurred by federal tax credits on solar equipment and rising fuel costs, more and more Southerners are warming to the idea of taking better advantage of the sun.
Among the latest signs of growing interest in solar in the South are these:
In North Carolina, some 170 builders have let the state alter their basic house design (free of charge) to include passive solar features such as extra south-side windows. Some 50 passive solar homes have been built as a result since August 1980, and state officials expect another 1,500 passive solar homes to be built by these same builders over the next two years.
North Carolina also recently began offering a 25 percent tax credit for passive solar features in homes.
Florida, which imports about 97 percent of its fuels, much of it foreign oil, and Texas are pushing ahead with research on passive solar cooling for homes. Under study are use of underground tubes to draw cooler air up through the home, six-inch concrete walls extending about five feet below ground, and insulation with foil on both sides to hold room heat in winter and keep out attic heat out in summer.
When an article in an Atlanta newspaper featured architect Richard Seedorf's passive solar home here last winter, the Georgia state solar office received some 300 calls and letters in the next two weeks asking how to build a solar home. Since then the state has held 11 crowded workshops with homeowners around the state.
Still, inflation, high interest rates, and expensive (and not always efficient) installations are casting shadows over the move to solar. And some officials say that federal budget cuts in solar promotional efforts will further slow the move.
There has not been enough interest in Georgia to spur passage of a solar tax credit on the state income tax, says state solar specialist Paul Burks. He estimates there are no more than 1,000 homes in the state with solar water heaters and another 300 to 500 with passive solar features.
''Things are stagnating,'' says Charles Mauk, who coordinates solar programs for the state of Texas. Inexperienced and costly installers are part of the problem, he says. And there are few distributors who carry all the items needed for solar hot water systems.
The rate of installation of solar-powered water heaters in Florida does not appear to be increasing, but is at least holding steady in the face of rising costs for equipment and installation, says Marvin Yarosh, associate director of the Florida Solar Energy Center.
What momentum there is in solar sales, Southern officials say, is propelled by the federal tax credit of 40 percent of a homeowner's investment in solar equipment - up to $4,000 a year off the amount of federal income tax owed. Elimination of the tax credit, an idea the Reagan administration has considered, would drastically halt sales, they say. The federal credit does not apply to passive solar features in homes.
Major federal cutbacks in promotional efforts mean the move to solar will be ''a much slower process,'' according to G. Barry Graves, director of the Southern Solar Engergy Center here. The center, one of four similar ones across the US, depends almost entirely on federal funds. Its previous work included considerable promotional efforts. The information efforts to industry need to be continued, he says.
Public perceptions, boosted by good examples of solar planning in homes, are important, he says.
In an effort to increase public confidence in solar equipment, Florida this year began requiring installers to pass written tests. During 1982 the state plans to run solar promotion announcements on television. And Florida's model energy code adopted in 1979 is being modified to give more credit to solar features in homes.