ENERGY CONSUMPTION: Where does the energy come from?

The energy resources consumed in the United States include:

• Petroleum
• Natural gas
• Coal
• Nuclear
• Hydropower
• Other (including solar, wind, and other renewables)

All of these are called primary energy sources.

Electricity is called a secondary energy source because we use primary sources to produce it. Usually, electricity is made at a power plant and sent through transmission lines to our homes, schools and businesses. Once it reaches these places, it is converted into other useful forms of energy like heat, light and sound.

In 1950, 15% of all the energy used in the U.S. went to generating electric power. Today almost 40% does. Electric power is an important part of our lives, and it is becoming more important.

NEXT: Making Electric Power