2. The coal cycle. The numbers in this illustration indicate the amount of carbon in each location in gigatons.

3. The fractional distillation of petroleum. The crude oil is vaporized, and the column separates the components according to their boiling points.

4. A coal-burning power plant for generating electricity. These plants, at best, are only 40% efficient. So 60% of of the energy from the fossil fuel is wasted as heat.

5. Percentages of electric power generation in the U.S. in the year 2000. Industry total is 3800 Billion Kilowatt hours

6. A nuclear power plant for generating electricity.