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?

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.

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.

Which has been growing more, energy to heat homes or energy to cool homes?

  • Sorry, that’s incorrect.

    Current trends indicate that by 2040 residential buildings will consume up to 28% less energy for heating but about 50% more for cooling. 

  • Correct!

    Current trends indicate that by 2040 residential buildings will consume up to 28% less energy for heating but about 50% more for cooling. 

  • Sorry, that’s incorrect.

    Current trends indicate that by 2040 residential buildings will consume up to 28% less energy for heating but about 50% more for cooling. 

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.

Which has been growing more, energy used by lighting and appliances or energy used for heating and cooling?

  • Correct!

    For decades, more than half of all residential energy use went  to space heating and cooling; in 1993, it accounted for nearly 60%. But EIA data show that by 2009, that share had dropped to 48%. And in the period 1993 to 2009, energy for appliances, electronics, and lighting rose from 24% to 35%, owing to the proliferation of appliances, as well as trends toward larger TVs and other devices.

  • Sorry, that’s incorrect.

    For decades, more than half of all residential energy use went  to space heating and cooling; in 1993, it accounted for nearly 60%. But EIA data show that by 2009, that share had dropped to 48%. And in the period 1993 to 2009, energy for appliances, electronics, and lighting rose from 24% to 35%, owing to the proliferation of appliances, as well as trends toward larger TVs and other devices.

Which of the following is considered an obstacle to cars running on hydrogen fuel cells?

  • Sorry, that’s incorrect.

    All of the reasons mentioned are considered obstacles to producing cars that run on hydrogen fuel cells.

  • Sorry, that’s incorrect.

    All of the reasons mentioned are considered obstacles to producing cars that run on hydrogen fuel cells.

  • Sorry, that’s incorrect.

    All of the reasons mentioned are considered obstacles to producing cars that run on hydrogen fuel cells.

  • Correct!

    All of the reasons mentioned are considered obstacles to producing cars that run on hydrogen fuel cells.

True or false? Wind energy generation is increasing in the United States.

  • Correct!

    In the United States, the amount of electricity generated from wind doubled between 2009 and 2014, and now makes up 18% of all renewable energy consumed and almost 2% of total U.S. energy use. 

  • Sorry, that’s incorrect.

    In the United States, the amount of electricity generated from wind doubled between 2009 and 2014, and now makes up 18% of all renewable energy consumed and almost 2% of total U.S. energy use. 

In 2014, what percentage of the United States' total energy consumption came from oil?

  • Sorry, that’s incorrect.

    In 2014, the United States got 35% of its energy from petroleum, and experts project that demand for this fuel will rise at least through 2020. 

  • Sorry, that’s incorrect.

    In 2014, the United States got 35% of its energy from petroleum, and experts project that demand for this fuel will rise at least through 2020. 

  • Sorry, that’s incorrect.

    In 2014, the United States got 35% of its energy from petroleum, and experts project that demand for this fuel will rise at least through 2020. 

  • Correct!

    In 2014, the United States got 35% of its energy from petroleum, and experts project that demand for this fuel will rise at least through 2020. 

What are ways that electricity system operators match power needs to generation on a day-to-day basis?

  • Sorry, that’s incorrect.

    Load-following and peaker plants, demand-response and energy storage are all ways that grid operators can adjust generation to meet demand.

  • Sorry, that’s incorrect.

    Load-following and peaker plants, demand-response and energy storage are all ways that grid operators can adjust generation to meet demand.

  • Sorry, that’s incorrect.

    Load-following and peaker plants, demand-response and energy storage are all ways that grid operators can adjust generation to meet demand.

  • Sorry, that’s incorrect.

    Load-following and peaker plants, demand-response and energy storage are all ways that grid operators can adjust generation to meet demand.

  • Correct!

     

    Load-following and peaker plants, demand-response and energy storage are all ways that grid operators can adjust generation to meet demand.

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

Nuclear Fusion

The union of two light atomic nuclei to form a heavier nucleus, resulting in the release of enormous amounts of energy.

View our full glossary