"The savings can be very significant for homeowners. Over the years I had read statements that shade trees reduce electricity consumption, so we wanted to put a dollar amount to it," the expert added. To reach the conclusion, the expert's office conducted a yearlong study of 160 houses in the Auburn, Ala., area to determine the annual energy savings provided by shade trees, primarily looking at the months of May to Sep.
He analyzed power bills, calculated shade coverage and surveyed the homeowners about household makeup, electricity-usage habits, square footage, type of air conditioning, appliances, roofing, exterior material and other factors.
"We looked at the amount of shade in the early morning, early afternoon and late afternoon. If you have trees on the west side of your house, you will have a much lower power bill," the expert said.
The study, which categorized types of shade into light, moderate and heavy, found that a house covered with 50 percent of light shade will save 10.3 percent.
Thermostat settings were important as well. "For each degree you raise your thermostat in the summer, you will save 3.3 percent on your power bill," he said. "We also found that children under age 12 are the major power consumers in the home. They watch television, play games and leave lights on," he added.