The process of generating electricity is the chief source of air emissions in the U.S., producing 1.2 billion tons of green house gases per year. That’s because the vast majority of our electric power comes from burning fossil fuels: coal, oil and natural gas.
When burned at power plants, coal, natural gas and oil release carbon dioxide, sulfur dioxide and nitrogen oxides. Of the three fuels, natural gas is the cleanest, emitting half as much carbon dioxide, less than a third as much nitrogen oxides and only 1% as much sulfur dioxide as coal.
Methane is an additional byproduct of burning oil. This gas also is frequently vented from coal during mining and transport. Methane is a component of natural gas, and it is sometimes emitted due to leaks or when natural gas is not burned completely.
These emissions can cause smog and acid rain, and they contribute to climate change. Everyone can help reduce these emissions by reducing their use of electricity.
- 21% of greenhouse gas emissions in the U.S. are attributable to residential energy use.
- 80% of existing homes could benefit from a retrofit that would reduce energy their energy consumption by as much as 40%.