The National Academies

What You Need To Know About Energy

Energy Efficiency

Increasing the energy supply is not the only answer to a stable energy future. Reducing demand through the improved efficiency of devices and procedures has the same end result. Learn about energy efficiency “wins” from the past and areas showing potential for the future.

Getting More for Less

The United States, with only 5% of the planet’s population, consumes 20% of the world’s total energy.

What’s “energy intensity” and why is it important when we consider how the United States will meet its future energy needs?

More about getting more for less

CAFE Standards

In 2007, Congress updated the CAFE standards, mandating that new cars, SUVs, and light trucks average 35 mpg by 2020.

The Corporate Average Fuel Economy (CAFE) standards set fuel efficiency requirements for all vehicles. Find out how these regulations affect our demand for oil.

More about CAFE standards

Industrial Efficiency

Industry accounts for about 31% of all the energy consumed in the United States, more than any other sector of the economy.

Seven industries are responsible for three-fourths of the energy used by the industrial sector. Which industries are the most energy-intensive and what are some targets for efficiency improvements?

More about industrial efficiency

Refrigeration

In the past 30 years, the amount of energy required to run a household refrigerator has been reduced by two-thirds.

In the mid-1970s, government and industry joined forces to research and develop improvements to the efficiency of household refrigerators. Find out more about this energy-efficiency success story.

More about refrigeration

Lighting

Lighting accounts for 18% of the electricity used in the United States.

Lighting is one area where great strides are being made in boosting energy efficiency. CFLs, for example, use energy more efficiently than traditional incandescent lightbulbs. What are LEDs and how might they introduce further improvements?

More about lighting

Heating & Cooling

In 2006, more than 40% of the energy delivered to residential buildings was used for space heating and cooling.

Controlling our indoor climate requires a lot of energy. Learn how advances in heating and cooling efficiency are helping to offset demographic, climate, and lifestyle trends that in recent years have been driving up the demand for energy.

More about heating & cooling

Energy Hands-on

Understanding Efficiency

Learn the significance of energy efficiency

Our Energy System

A visualization of all our energy sources

What do you know about energy?

As an automobile fuel, what amount of hydrogen compares with a gallon of gasoline?

Correct!

A gallon of gasoline contains about the same energy as a kg of hydrogen. Although fuel cells are expected to be twice as efficient as gasoline vehicles, hydrogen is very diffuse and storing an ample supply on board represents an engineering challenge.
Sorry, that’s incorrect.

A gallon of gasoline contains about the same energy as 1 kg of hydrogen. Although fuel cells are expected to be twice as efficient as gasoline vehicles, hydrogen is very diffuse and storing an ample supply on board represents an engineering challenge.
Sorry, that’s incorrect.

A gallon of gasoline contains about the same energy as a kg of hydrogen. Although fuel cells are expected to be twice as efficient as gasoline vehicles, hydrogen is very diffuse and storing an ample supply on board represents an engineering challenge. Take the full quiz to learn your energy IQ.

Energy Defined

Photovoltaic (PV) Cell: Sometimes referred to as a solar cell, a device that utilizes the photoelectric effect to convert incident sunlight directly into electricity. This can be distinguished from solar thermal energy, which is sometimes used to create electricity indirectly.

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