All of the above are emitted from coal-fired power plants and can be harmful to our health and the environment.

All of the above are emitted from coal-fired power plants and can be harmful to our health and the environment.

All of the above are emitted from coal-fired power plants and can be harmful to our health and the environment.

All of the above are emitted from coal-fired power plants and can be harmful to our health and the environment.

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. 

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. 

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. 

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

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

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

CO2 concentration in the atmosphere has risen about 43% since the beginning of the industrial revolution in the mid-eighteenth century-half of that since 1980

CO2 concentration in the atmosphere has risen about 43% since the beginning of the industrial revolution in the mid-eighteenth century-half of that since 1980

CO2 concentration in the atmosphere has risen about 43% since the beginning of the industrial revolution in the mid-eighteenth century-half of that since 1980

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.

U.S. energy consumption is projected to rise 9% by 2040, or 0.3% per  year, while global consumption will increase about 50% over the same period 

U.S. energy consumption is projected to rise 9% by 2040, or 0.3% per  year, while global consumption will increase about 50% over the same period 

U.S. energy consumption is projected to rise 9% by 2040, or 0.3% per  year, while global consumption will increase about 50% over the same period 

U.S. energy consumption is projected to rise 9% by 2040, or 0.3% per  year, while global consumption will increase about 50% over the same period 

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

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. 

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. 

Extraction of "tight" oil—light crude oil contained in geological formations of shale or sandstone—accounted for only 12% of total U.S. oil production in 2008. By 2012, it made up 35%, and is predicted to rise to 50% in the near term.