The National Academies

The National Academies: What You Need To Know About Energy

What You Need To Know About Energy

Our Energy Sources

Fossil Fuels

The United States gets 81% of its total energy from oil, coal, and natural gas, all of which are fossil fuels. We depend on those 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 decline as the planet’s known supplies diminish, the difficulty and cost of tapping remaining reserves increase, and the effect of their continued use on our planet grows more critical. But shifting to new energy sources will take time. In the meantime, how do we use fossil fuels in the most efficient and environmentally responsible way possible?



In 2015, 33.2% of U.S. electricity came from coal— roughly equal to natural gas (32.7%), but greater than nuclear power (20%) or renewable energy sources (13%).

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

More about coal



America relies on its domestic supplies as well as imports of petroleum—about one-quarter of the amount we consume—from a handful of nations.

The United States depends heavily on oil, which accounts for 92% of all consumption in the transportation sector and 26% in the industrial sector. Learn about the implications of continuing to rely heavily on this energy source.

More about oil

Natural Gas

Natural Gas

The United States has abundant deposits of natural gas and imports less than 4% of the total amount consumed annually—chiefly from Canada .

In 2015, 29% 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

Explore Other Topics

Energy Hands-on

The Promise of Better Lighting

Energy savings through lighting technology

Energy Defined

Corporate Average Fuel Economy (CAFE)

Federal standards that stipulate a target average fuel economy rating (typically expressed in miles per gallon, or mpg) to be met by passenger vehicles by a certain date. The most recent version of the CAFE law, pending passage by Congress, requires new cars, SUVs, and light trucks to average 35.5 mpg by 2016.

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