Some More Tree Facts

A study of Chicago’s urban forest found that increasing tree cover by 10 per cent (an additional three trees per building) would reduce total heating and cooling energy use by 5 to 10 per cent . At a national level, researchers estimate that planting three additional trees for each building in the United States could save more than US$2 billion in energy costs annually (McPherson, 1994; Akbari et al., 1988).

Tree windbreaks have been found to reduce residential heating costs by 10-15 percent, while shade and evapotranspirational cooling from trees have been found to reduce cooling costs by 20-50 percent (Dwyer, 1993; Laverne and Lewis, 1995).

A recent study found that planting shade trees could reduce the need for power plants. Data from California shows that 50 million shade trees planted in strategic, energy-saving locations could eliminate the need for seven 100-megawatt power plants (McPherson and Simpson, 2001).