By E. Gregory McPherson and Rowan A. Rowntree
(November 1993)- Findings from monitoring and computer simulation studies indicate that trees can be a cost-effective energy conservation measure for some electric utilities. Simulations suggest that a single 25-ft tall tree can reduce annual heating and cooling costs of a typical residence by 8 to 12 percent ($10-25). Assuming annual savings of $10 per household, a nationwide residential tree planting program could eventually save about $1 billion each year.
A study of the potential for energy-conserving shade tree plantings within residential sections of San Diego found that over 40 percent of all houses surveyed had space available for a tree opposite their west wall. The largest benefits were attributed to property value enhancement, energy savings, avoided stormwater runoff, and atmospheric carbon removal, while greatest projected costs were from pruning, planting, and program administration.
Cited Journal Article on Trees and Energy Conservation (PDF)
Journal of Arboriculture