A graphic representation of U.S. energy use in 2000 (the latest available, but little has changed.)

What does it tell us?

• Petroleum, both imported and domestic, is our biggest source of energy.
• We use roughly as much imported petroleum as coal.
• We also get a great deal of energy from natural gas, and to a lesser extent, nuclear power.
• The energy we derive from hydropower, biomass, and “other” (namely, solar and wind) is middling.
• Our petroleum is dedicated mostly to transportation, but some of it is siphoned off for industrial, residential, and commercial uses.
• Other sources of energy are dedicated almost entirely to electricity, and the majority of that is wasted in the system.
• And speaking of wasted energy, almost two-thirds of all energy used in the U.S. is rejected — leaked out the envelopes of our homes and offices, lost in the inefficient processes of the combustion engine.

The flow chart was created by the Lawrence Livermore National Laboratory (operated by the University of California for the U.S. Department of Energy.)