The National Academies: What You Need To Know About Energy

The National Academies

What You Need To Know About Energy

Our Energy Sources

Emerging Technologies

No matter how the U.S. energy portfolio changes, an increasing share of future needs will be met by technologies now in the research or development stage. Some will require substantial improvements—or even research breakthroughs—to have a major impact on our energy budget.

Here are some of the options. Whether and to what extent any of these technologies ultimately contributes to changing our energy future will depend on many factors, from advances in technology development to the priorities reflected in government policy.

Advanced Nuclear Fission

Nuclear power plants account for 20% of U.S. electricity generation, but no new reactors have come on line since 1996.

The need to reduce CO2 emissions is renewing interest in nuclear energy. What are the new nuclear technologies and how do they improve upon existing nuclear plants?

More about advanced nuclear fission

Hydrogen Fuel Cells

There are no natural reservoirs of pure hydrogen; this resource must be extracted from compounds such as natural gas or water.

Hydrogen fuel cells have the potential to drastically reduce U.S. dependence on foreign sources of energy. What are fuel cells and how close are we to a nationwide “hydrogen economy”?

More about hydrogen fuel cells

Alternatives to Conventional Oil

A region covering parts of Colorado, Utah, and Wyoming contains oil shale totaling about three times the proven oil reserves of Saudi Arabia.

Tar sands, oil shale, and heavy crude oil could greatly affect U.S. oil supply in the future. Find out what these sources are, where they can be found, and how they might influence our energy situation.

More about alternatives to conventional oil

Electric Vehicles

Today's all-electric vehicles can travel up to 300 miles emissions-free on a single battery charge.

New energy technologies are working toward vehicles with reduced dependence on fossil fuels like gasoline, diesel, and natural gas. Learn about two such technologies—all-electric vehicles and plug-in hybrid electric vehicles—and their potential contributions.

More about electric vehicles

Advanced Coal Technologies

Coal accounts for about one-third of U.S. CO2 emissions.

Coal is an inexpensive and abundant domestic energy resource. But it’s also a major contributor to carbon dioxide emissions. Learn about IGCC plants and other “clean coal” technologies that are designed to capture and sequester CO2.

More about advanced coal technologies


The U.S. Energy Independence and Security Act of 2007 stipulates that by 2022 we must produce 21 billion gallons of advanced biofuels, such as cellulosic ethanol.

Our nation already offsets some of its dependence on fossil fuels with biodiesel and corn-based ethanol. What are these alternatives to gasoline and diesel and how will they affect our energy supply?

More about biofuels

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Energy Hands-on

What do you know about energy?

Renewable energy (solar, wind, geothermal, hydroelectric, biofuels, waste, and wood) accounted for what percentage of the total energy supply in the United States in 2008?

  • Sorry, that’s incorrect.

    Renewable energy accounted for 7% of the total U.S. energy supply in 2008, less than any other type of energy source.

  • Correct!

    Renewable energy accounted for 7% of the total U.S. energy supply in 2008, less than any other type of energy source.

  • Sorry, that’s incorrect.

    Renewable energy accounted for 7% of the total U.S. energy supply in 2008, less than any other type of energy source.

Energy Defined

Climate Change

The process of shifting from one prevailing state in regional or global climate to another. Often used interchangeably with “global warming,” scientists sometimes also use the term to refer to periods of climatic cooling. Climate change is typically the preferred term over “global warming” because it helps convey that there are climate changes in addition to rising temperatures.

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National Academies Press

Search the National Academies Press website by selecting one of these related terms.