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?

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. 

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.

What type of transportation uses the most total energy?

  • Correct!

    By far the largest share of energy in transportation is consumed by cars, light trucks, and motorcycles—about 58% in 2012, followed by other trucks (21%), aircraft (9%), boats and ships (3%), and trains and buses (3%). Pipelines account for 3% and military uses for 2%.

  • Sorry, that’s incorrect.

    By far the largest share of energy in transportation is consumed by cars, light trucks, and motorcycles—about 58% in 2012, followed by other trucks (21%), aircraft (9%), boats and ships (3%), and trains and buses (3%). Pipelines account for 3% and military uses for 2%.

  • Sorry, that’s incorrect.

    By far the largest share of energy in transportation is consumed by cars, light trucks, and motorcycles—about 58% in 2012, followed by other trucks (21%), aircraft (9%), boats and ships (3%), and trains and buses (3%). Pipelines account for 3% and military uses for 2%.

  • Sorry, that’s incorrect.

    By far the largest share of energy in transportation is consumed by cars, light trucks, and motorcycles—about 58% in 2012, followed by other trucks (21%), aircraft (9%), boats and ships (3%), and trains and buses (3%). Pipelines account for 3% and military uses for 2%.

  • Sorry, that’s incorrect.

    By far the largest share of energy in transportation is consumed by cars, light trucks, and motorcycles—about 58% in 2012, followed by other trucks (21%), aircraft (9%), boats and ships (3%), and trains and buses (3%). Pipelines account for 3% and military uses for 2%.

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. 

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.

What percentage of harvested corn was used to produce ethanol in the U.S. in 2014?

  • Sorry, that’s incorrect.

    In 2014, about 38% of harvested corn in the US went to make ethanol and its associated coproducts

  • Sorry, that’s incorrect.

    In 2014, about 38% of harvested corn in the US went to make ethanol and its associated coproducts

  • Correct!

    In 2014, about 38% of harvested corn in the US went to make ethanol and its associated coproducts

  • Sorry, that’s incorrect.

    In 2014, about 38% of harvested corn in the US went to make ethanol and its associated coproducts

  • Sorry, that’s incorrect.

    In 2014, about 38% of harvested corn in the US went to make ethanol and its associated coproducts

  • Sorry, that’s incorrect.

    In 2014, about 38% of harvested corn in the US went to make ethanol and its associated coproducts

How many gallons of water are required to hydraulically fracture a well, on average in the U.S.?

  • Sorry, that’s incorrect.

    The national average is around 1.5 million gallons per well , according to the EPA.

  • Sorry, that’s incorrect.

    The national average is around 1.5 million gallons per well , according to the EPA.

  • Sorry, that’s incorrect.

    The national average is around 1.5 million gallons per well , according to the EPA.

  • Correct!

    The national average is around 1.5 million gallons per well , according to the EPA.

Refrigerators became 70% more efficient between 1972 and 2001, primarily due to regulation. What is a market response to increased efficiency of refrigerators?

  • Sorry, that’s incorrect.

    Refrigerators are not likely to be used more or less hours in the day, but people are more likely to have more of them if they cost less to operate.

  • Sorry, that’s incorrect.

    Refrigerators are not likely to be used more or less hours in the day, but people are more likely to have more of them if they cost less to operate.

  • Correct!

    Refrigerators are not likely to be used more or less hours in the day, but people are more likely to have more of them if they cost less to operate.

Combustion of gasoline and diesel fuel emits which of the following?

  • Sorry, that’s incorrect.

    All of the above are emitted by vehicles running on gasoline and diesel fuel.

  • Sorry, that’s incorrect.

    All of the above are emitted by vehicles running on gasoline and diesel fuel.

  • Sorry, that’s incorrect.

    All of the above are emitted by vehicles running on gasoline and diesel fuel.

  • Sorry, that’s incorrect.

    All of the above are emitted by vehicles running on gasoline and diesel fuel.

  • Correct!

    All of the above are emitted by vehicles running on gasoline and diesel fuel.

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