Energy Production
To have coal, oil or gas to produce electricity at generating stations, you need to mine or extract it first. Then you need to transport it. Gas-guzzling machinery is often used, and natural gas escapes. In other words, a lot of greenhouse gas is produced that doesn’t even get used to generate electricity or power cars.
Read more : http://www.ehow.com/facts_5939247_carbon-footprint-information-kids.html