Heat island effect occurs when warmer temperatures are experienced in urban landscapes compared to adjacent rural areas as a result of solar energy retention on constructed surfaces. Principal surfaces that contribute to the heat island effect include streets, sidewalks, parking lots and buildings. Trees, green roofs (see above), reflective coloring, vegetated landscaping, and bodies of water mitigate the heat island effect.

Hybrid vehicles use a gasoline engine to power an electric generator. The generator, together with storage batteries, powers electric motors that drive the vehicle’s wheels. Hybrid vehicles use less gasoline and produce less pollution compared to conventional vehicles of similar size.