The National Academies

The National Academies: What You Need To Know About Energy

What You Need To Know About Energy

What do you know about energy?

What technology was most responsible for increase in lighting efficiency from 45 Im/W in 2001 to 58 Im/W in 2010?

  • Sorry, that’s incorrect.

    Increasing market share of compact fluorescents was primarily responsible for the increased lighting efficiency between 2001 and 2010.

  • Sorry, that’s incorrect.

    Increasing market share of compact fluorescents was primarily responsible for the increased lighting efficiency between 2001 and 2010.

  • Correct!

    Increasing market share of compact fluorescents was primarily responsible for the increased lighting efficiency between 2001 and 2010.

  • Sorry, that’s incorrect.

    Increasing market share of compact fluorescents was primarily responsible for the increased lighting efficiency between 2001 and 2010.

True or false? Fuel cells store energy.

  • Sorry, that’s incorrect.

    Fuel cells are an efficient way to convert hydrogen to electricity, but the energy is stored in the hydrogen.

  • Correct!

    Fuel cells are an efficient way to convert hydrogen to electricity, but the energy is stored in the hydrogen.

Renewable energy (solar, wind, geothermal, hydroelectric, biofuels, waste, and wood) accounted for what percentage of the total energy supply in the United States in 2014?

  • Correct!

    In 2014, 10% of our total energy use came from renewable energy sources, such as biomass, wind, solar, and hydropower.

  • Sorry, that’s incorrect.

    In 2014, 10% of our total energy use came from renewable energy sources, such as biomass, wind, solar, and hydropower.

  • Sorry, that’s incorrect.

    In 2014, 10% of our total energy use came from renewable energy sources, such as biomass, wind, solar, and hydropower.

  • Sorry, that’s incorrect.

    In 2014, 10% of our total energy use came from renewable energy sources, such as biomass, wind, solar, and hydropower.

Between 1980 and 2012, after fuel economy standards where put in place, which of the following has happened to vehicles?

  • Sorry, that’s incorrect.

    Improved vehicle efficiency has allowed for increases in weight, horsepower and fuel economy.

  • Sorry, that’s incorrect.

    Improved vehicle efficiency has allowed for increases in weight, horsepower and fuel economy.

  • Sorry, that’s incorrect.

    Improved vehicle efficiency has allowed for increases in weight, horsepower and fuel economy.

  • Correct!

    Improved vehicle efficiency has allowed for increases in weight, horsepower and fuel economy.

On average, which is most efficient in coverting heat into electic power?

  • Sorry, that’s incorrect.

    On average, a typical coal-burning power plant in 2013 was about 33% efficient in converting heat energy into electrical power. A gas-fired plant was about 42% efficient. And in natural gas combined-cycle power plants—in which waste heat from a natural gas turbine is used to power a steam turbine—generation may be as much as 60% efficient.

  • Sorry, that’s incorrect.

    On average, a typical coal-burning power plant in 2013 was about 33% efficient in converting heat energy into electrical power. A gas-fired plant was about 42% efficient. And in natural gas combined-cycle power plants—in which waste heat from a natural gas turbine is used to power a steam turbine—generation may be as much as 60% efficient.

  • Correct!

    On average, a typical coal-burning power plant in 2013 was about 33% efficient in converting heat energy into electrical power. A gas-fired plant was about 42% efficient. And in natural gas combined-cycle power plants—in which waste heat from a natural gas turbine is used to power a steam turbine—generation may be as much as 60% efficient.

How efficient are ordinary commercial solar cell units?

  • Sorry, that’s incorrect.

    As of 2014, the very best experimental units could convert more than 40% of light energy to electricity; ordinary commercial units are in the range of 5% to 20%. 

  • Sorry, that’s incorrect.

    As of 2014, the very best experimental units could convert more than 40% of light energy to electricity; ordinary commercial units are in the range of 5% to 20%. 

  • Correct!

    As of 2014, the very best experimental units could convert more than 40% of light energy to electricity; ordinary commercial units are in the range of 5% to 20%. 

  • Sorry, that’s incorrect.

    As of 2014, the very best experimental units could convert more than 40% of light energy to electricity; ordinary commercial units are in the range of 5% to 20%. 

In 2014, how much of the world's CO2 is released by the United States?

  • Sorry, that’s incorrect.

    The United States emits about 18% of the world’s greenhouse gases, behind only China, which accounts for approximately one-quarter of total global emissions. 

  • Correct!

    The United States emits about 18% of the world’s greenhouse gases, behind only China, which accounts for approximately one-quarter of total global emissions. 

  • Sorry, that’s incorrect.

    The United States emits about 18% of the world’s greenhouse gases, behind only China, which accounts for approximately one-quarter of total global emissions. 

  • Sorry, that’s incorrect.

    The United States emits about 18% of the world’s greenhouse gases, behind only China, which accounts for approximately one-quarter of total global emissions. 

Nuclear power provided what percentage of the total U.S. energy supply in 2013?

  • Sorry, that’s incorrect.

    19% of our electricity was generated  by nuclear fuel in 2013. 

  • Correct!

    19% of our electricity was generated  by nuclear fuel in 2013. 

  • Sorry, that’s incorrect.

    19% of our electricity was generated  by nuclear fuel in 2013. 

  • Sorry, that’s incorrect.

    19% of our electricity was generated  by nuclear fuel in 2013. 

How are battery electric vehicles and hybrid vehicles different?

  • Sorry, that’s incorrect.

    Battery electric vehicles have only a motor and battery, they recharge from the grid and their carbon emissions depend on the energy used to generate the electricity they use. Hybrid vehicles have both a gasoline engine and an electric motor, and use petroleum onboard when their batteries are exhausted. Some hybrid vehicles can charge from the grid and others cannot. 

  • Sorry, that’s incorrect.

    Battery electric vehicles have only a motor and battery, they recharge from the grid and their carbon emissions depend on the energy used to generate the electricity they use. Hybrid vehicles have both a gasoline engine and an electric motor, and use petroleum onboard when their batteries are exhausted. Some hybrid vehicles can charge from the grid and others cannot. 

  • Sorry, that’s incorrect.

    Battery electric vehicles have only a motor and battery, they recharge from the grid and their carbon emissions depend on the energy used to generate the electricity they use. Hybrid vehicles have both a gasoline engine and an electric motor, and use petroleum onboard when their batteries are exhausted. Some hybrid vehicles can charge from the grid and others cannot. 

  • Sorry, that’s incorrect.

    Battery electric vehicles have only a motor and battery, they recharge from the grid and their carbon emissions depend on the energy used to generate the electricity they use. Hybrid vehicles have both a gasoline engine and an electric motor, and use petroleum onboard when their batteries are exhausted. Some hybrid vehicles can charge from the grid and others cannot. 

  • Correct!

    Battery electric vehicles have only a motor and battery, they recharge from the grid and their carbon emissions depend on the energy used to generate the electricity they use. Hybrid vehicles have both a gasoline engine and an electric motor, and use petroleum onboard when their batteries are exhausted. Some hybrid vehicles can charge from the grid and others cannot. 

Place this badge on your facebook page to show your friends what you know about energy.

Get the badge

Place this badge on your facebook page to show your friends what you know about energy.

Get the badge

OR, get a higher score to unlock a different badge.

Retake the quiz

Place this badge on your facebook page to show your friends what you know about energy.

Get the badge

OR, get a higher score to unlock a different badge.

Retake the quiz

Explore Other Topics

Energy Hands-on

The Promise of Better Lighting

Energy savings through lighting technology

Energy Defined

Ocean Acidification

The process by which the hydronium ion concentration increases in the ocean, measured as decreasing pH. One source of ocean acidification is the dissolution of carbon dioxide, which forms carbonic acid with water and then dissociates into hydronium and bicarbonate. Lower pH impacts ocean life, including their soft and hard materials, and also human-built structures in the ocean, such as vessels.

View our full glossary