Our homes hum with electric power, and our neighborhoods are scattered with the poles and wires that deliver it to us. What's less visible is the air and water pollution this system produces.

Generally speaking, the burning of nonrenewable resources creates greenhouse gases, including carbon dioxide, and emits mercury, nitrogen oxide, and sulfur dioxide that dissolve in rain particles and fall to earth (this is known as acid rain). The mercury contaminates fish in our waterways that we then catch and eat, poisoning ourselves.

Even if you don't live near a coal power plant, the pollution travels. New England forests are being harmed by mercury smog from power plants in the Midwest, and there is evidence now that emissions from Chinese power plants are reaching the West Coast of America. That's quite a system.

Find out where our electricity comes from and how we can do better in "Planet Home: Conscious Choices for Cleaning & Greening the World You Care About Most."