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.

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.

In 2014, the industrial sector represented 32% of U.S. energy use, while transportation was 28%. Residential and commercial were 22% and 19% respectively.

In 2014, the industrial sector represented 32% of U.S. energy use, while transportation was 28%. Residential and commercial were 22% and 19% respectively.

In 2014, the industrial sector represented 32% of U.S. energy use, while transportation was 28%. Residential and commercial were 22% and 19% respectively.

As of 2014, total world consumption was approximately 92 million barrels per day, about 19 million or 21% of which were used by the United States.

As of 2014, total world consumption was approximately 92 million barrels per day, about 19 million or 21% of which were used by the United States.

As of 2014, total world consumption was approximately 92 million barrels per day, about 19 million or 21% of which were used by the United States.

A typical incandescent lamp (traditional light bulb) that consumes 60 watts of power produces around 800 lumens. A compact fluorescent lamp emits the same amount of light while using only 13 watts. And an LED lamp consumes only 10 watts to give off the same 800 lumens.

A typical incandescent lamp (traditional light bulb) that consumes 60 watts of power produces around 800 lumens. A compact fluorescent lamp emits the same amount of light while using only 13 watts. And an LED lamp consumes only 10 watts to give off the same 800 lumens.

A typical incandescent lamp (traditional light bulb) that consumes 60 watts of power produces around 800 lumens. A compact fluorescent lamp emits the same amount of light while using only 13 watts. And an LED lamp consumes only 10 watts to give off the same 800 lumens.

New technologies for drilling have led to increases in supply of oil in the U.S. in the decade up to 2014.

New technologies for drilling have led to increases in supply of oil in the U.S. in the decade up to 2014.

New technologies for drilling have led to increases in supply of oil in the U.S. in the decade up to 2014.

New technologies for drilling have led to increases in supply of oil in the U.S. in the decade up to 2014.

Wood and waste biomass, along with biofuels, accounted for about 50% of the U.S. renewable energy supply in 2014, and more than 4% of all energy consumed. 

Wood and waste biomass, along with biofuels, accounted for about 50% of the U.S. renewable energy supply in 2014, and more than 4% of all energy consumed. 

Wood and waste biomass, along with biofuels, accounted for about 50% of the U.S. renewable energy supply in 2014, and more than 4% of all energy consumed. 

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

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

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

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

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

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

On average, even after passing through hundreds of kilometers of air on a clear day, solar radiation reaches Earth with enough energy in a single square meter to run a mid-size desktop computer-if all the sunlight could be captured and converted to electricity.

On average, even after passing through hundreds of kilometers of air on a clear day, solar radiation reaches Earth with enough energy in a single square meter to run a mid-size desktop computer-if all the sunlight could be captured and converted to electricity.