Living quietly on a small farm in Montevallo is a forerunner in the efforts to utilize solar energy. Terry Arnold made significant strides in that endeavor in the early 1980s when he designed and built nine homes in Walden Court in Montevallo. The homes have a passive solar system Arnold calls a Sunfunnel heating system.

Arnold’s involvement in developing solar energy homes happened at a time in his life when he was the manager of Alabama Power’s Environmental and Research Services, and was looking for a change of direction and a new adventure.

“The Sunfunnel system is a simple one,” Arnold said. “The homes are built with the solar collector on the south side. The collector is a large glass surface angled above an open space n the house so that as the sun comes through, it mainly strikes the floor. Inside that glass is a moveable wall, hinged at the bottom and angled when open, that it takes advantage of the sun’s rays. A key to the system is the heavy concrete floor on the bottom floor or basement that stores the heat from the sun in the daytime and then naturally releases it to keep the house warm at night. The wall is closed at night to keep the heat from escaping through the glass.”

One section of the glass is designed as a solar collector for heating water.

During the first year the homes were occupied, electric metering indicated large saving in the use of electricity. In the late 1980s Arnold built the home in Indian Highlands with the Sunfunnel system that Nathan and Martha McMinn own.

“We use the solar collectors for heating water all of the time and the system for heating the house when I am available to operate it,” Nathan McMinn said. “The savings are phenomenal, the electric bill for our 2200 sq. ft. home is never more than $120. The system has paid for itself many times over.”

The original passive Sunfunnel system requires that the occupant of the house be active and actually be a part of the operation loop. With today’s technology, the system could be easily automated, but Arnold thinks personal involvement is a large part of the fun.

Arnold is very excited about the future of solar energy and particularly looks forward to the day that electricity is generated by the sun not only to supply that necessary for residential use, but to power electric automobiles as well.

Catherine Legg can be reached at clegg2@bellsouth.net.