Petroleum

An offshore oil platform is seen in Huntington Beach, California, on September 28, 2014. Source: Lucy Nicholson/Reuters.

An offshore oil platform is seen in Huntington Beach, California, on September 28, 2014.

Source: Lucy Nicholson/Reuters

Origins and Uses

Petroleum formed when organic matter like dead marine organisms experienced intense heat and pressure under layers of sedimentary rock. Extracted through drilling or hydraulic fracturing, petroleum refers to crude oil and other petroleum products, which are refined into usable fuels such as gasoline, jet fuels, kerosene, and diesel.

Tradeoffs

  • High net energy yield (energy it provides outweighs energy needed to provide it)
  • Highly mobile, allows for easy transport
  • Low land use
  • Lower cost to consumers than other energy sources
  • Well-developed technology, especially for use in automobiles
  • The global supply of oil could run out by 2068
  • Drilling, production, and use degrade habitats for fish and birds and pollute the air; spills pollute drinking water
  • Government subsidies obscure environmental costs not reflected in the market price

Did you know?

In its World Energy Outlook 2017 report, the International Energy Agency concluded that the United States is on course to become a net exporter of oil within a decade and a dominant oil and gas producer over the next few decades, due to advances in hydraulic fracturing and offshore drilling.

Coal

A driver gets off a loading vehicle at a small coal depot near a coal mine of the state-owned Longmay Group on the outskirts of Jixi, in Heilongjiang province, China, on October 23, 2015. Source: Jason Lee/Reuters.

A driver gets off a loading vehicle at a small coal depot near a coal mine of the state-owned Longmay Group on the outskirts of Jixi, in Heilongjiang province, China, on October 23, 2015.

Source: Jason Lee/Reuters

Origins and Uses

Coal is the world’s most abundant fossil fuel. It is a carbon-rich sedimentary rock that formed over hundreds of millions of years when plant matter physically and chemically transformed under layers of water and dirt. Coal extraction occurs through surface mining, in which machines clear away the uppermost layers of rock and soil, and underground mining, in which machines and miners remove coal deep below ground level.

Tradeoffs

  • Mining can cause permanent land disturbance
  • Coal mining and burning can pollute water and air, contributing to climate change and health problems
  • Coal produces high CO2 emissions
  • Government subsidies obscure environmental costs not reflected in the market price

Did you know?

In Beijing, smog from coal burning power plants can reach such a point that schools close and farmers panic over lack of sunlight. The pollution also causes myriad health effects: early deaths, heart and lung problems, cancer, diabetes, and birth defects.

Natural Gas

Natural gas flares are seen at an oil pump site outside of Williston, North Dakota, on March 11, 2013. Source: Shannon Stapleton/Reuters.

Natural gas flares are seen at an oil pump site outside of Williston, North Dakota, on March 11, 2013.

Source: Shannon Stapleton/Reuters

Origins and Uses

Natural gas forms in much the same way petroleum does; however, petroleum forms under a smaller range of heat and pressure, known as the oil window, whereas natural gas can form under a much broader range of temperatures. Advances in horizontal drilling and hydraulic fracturing (also known as fracking) have unlocked vast reserves of natural gas, on top of the reserves that are extracted from conventional drilling.

Tradeoffs

  • High net energy yield (energy it provides outweighs energy needed to provide it)
  • Large reserves
  • Lower cost to consumers than other energy sources
  • Natural gas power plants emit 50-60 percent less CO2 compared to a coal plants
  • Relatively lower land use compared to other fossil fuels
  • Burning natural gas releases CO2 and contributes to air pollution and smog
  • Extraction can result in high carbon emissions through methane leaks
  • Extraction, especially through fracking, can also contribute to water contamination and more frequent earthquakes
  • Transportation can be difficult and dangerous

Did you know?

In 2014, inefficiencies in the extraction of natural gas in the United States wasted enough energy to power over 3.5 million U.S. households, due to a process called flaring in which producers must burn the release of natural gas to prevent the release of methane.