Urban trees and forests alter building energy use and associated emissions from power plants by shading buildings, cooling air temperatures and altering wind speeds around buildings. Field data on urban trees were combined with local urban/community tree and land cover maps, modeling of tree effects on building energy use and pollutant emissions, and state energy and pollutant costs to estimate tree effects on building energy use and associated pollutant emissions at the state to national level in the conterminous United States.
- Trees and forests in urban/community areas in the coterminous United States annually reduce electricity use by 38.8 million MWh ($4.7 billion), heating use by 246 million MMBtus ($3.1 billion) and avoid thousands of tonnes of emissions of several pollutants valued at $3.9 billion per year.
- Average reduction in national residential energy use due to trees is 7.2percent.
- Specific designs to reduce energy use using urban trees could increase these values and further reduce energy use and improve air quality in the United States.