Want to do something about global warming and save money? Start at home. Our humble abodes are responsible for an estimated 20 percent of carbon dioxide emissions. That’s because they burn through unneeded energy in an attempt to keep poorly insulated kilowatt gobblers a-hummin’. Since 1979 way before green was chic DENNIS CREECH, the executive director of Southface Energy Institute, has been teaching home builders and owners how to use less water, harness the sun as an energy source and make your home more friendly to the Earth upon which it sits. Southface’s EarthCraft green-home program has become the go-to template for builders and owners who desire a house that’s imagine this well-built and efficient. In fact, EarthCraft recently was named the best green-home building program in the nation by the National Association of Home Builders. www.southface.org.