The National Academies: What You Need To Know About Energy

The National Academies

What You Need To Know About Energy

Our Energy Sources

Fossil Fuels

The United States gets 84% of its total energy from oil, coal, and natural gas, all of which are fossil fuels. We depend on fossil fuels to heat our homes, run our vehicles, power industry and manufacturing, and provide us with electricity. Eventually, the degree to which we depend on fossil fuels will have to lessen as the planet’s known supplies diminish, the difficulty and cost of tapping remaining reserves increases, and the effect of their continued use on our planet grows more dire. But shifting to new energy sources will take time. In the meantime, what do we need to know about fossil fuels?


In 2008, 49% of U.S. electricity came from coal, more than twice the contribution of either nuclear power or natural gas.

There is an abundant supply of coal in the United States and it’s a relatively inexpensive energy source. What are the costs of mining and burning this resource, though, and is there a good way to address them?

More about coal


Almost two-thirds of the oil America uses is imported from a handful of nations.

The United States depends heavily on oil, which fuels nearly the entire transportation sector and a significant portion of the industrial sector. Learn about the risks of continuing to rely on this convenient, transportable energy source.

More about oil

Natural Gas

The United States imports less than 2% of its natural gas from outside North America.

In 2008, 24% of the U.S. total energy supply came from natural gas. Learn why this resource is often described as “clean burning” and consider the costs and benefits of its use.

More about natural gas

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Energy Videos

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America's Energy Future

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Energy Hands-on

What do you know about energy?

True or False: Increasing the energy supply is the only answer to a stable energy future.

  • Sorry, that’s incorrect.

    Reducing demand through the improved efficiency of devices and procedures is another way to improve our energy situation.

  • Correct!

    Reducing demand through the improved efficiency of devices and procedures is another way to improve our energy situation.

Energy Defined


A unit of measure used to describe very large quantities of energy, such as the annual energy output of the United States. One quad is equal to one quadrillion—that is, one million billion, or 1015—Btu.

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National Academies Press

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