The Carbon Cycle for Biodiesel

The use of biofuels is balanced by plant matter already in the ecosystem. There is no net increase in carbon dioxide in the atmosphere.

Plants turn carbon dioxide into sugars and oils using solar energy.
Biofuels (oil, biodiesel and ethanol) are made.
Fuels are burned to release carbon dioxide.
Carbon dioxide (a greenhouse gas) is released into the atmosphere.

The Carbon Cycle for Petroleum

Crude oil is pumped from deposits in the earth.
Crude is refined into fuel.
Fuel is burned to release carbon dioxide.
Carbon dioxide is released into the atmosphere. More carbon dioxide is released than plants can process so carbon dioxide begins to build up in the atmosphere, contributing to global warming.

The earth was a very different place during the Carboniferous period (about 300 million years ago) when it is commonly thought that most fossil fuels were formed. Most of the land was concentrated in one large continent instead of the seven that we know today. Carbon dioxide levels were at least twice as high as they are today. Even the plants and animals that lived during that time were different. The majority of them are now extinct.

Last Updated 5/2/06