Turning oil into fuel is a complex process, with environmental and human impacts at every stage.
Oil is extracted by drilling, fracking, or mining. Drilling can lead to costly oil spills and life-threatening accidents, as evidenced by the 2010 Deepwater Horizon disaster. Certain drilling, fracking, and mining operations involve the venting and burning of methane or natural gas, leading to increased global warming emissions. And water used in tar sands mining has created large toxic storage ponds, including nearly 70 square miles of tailing ponds in Alberta Canada alone.
Once extracted, crude oil is transported via pipelines, barges, tankers, trains, and trucks to processing facilities where it's refined into usable products. Oil spills during transportation are increasingly common and difficult to clean up, while refining the oil can be very energy intensive, particularly for unconventional oils.
When used, one gallon of gasoline emits about 19 pounds of global warming gases, compared to roughly five to fifteen pounds produced during extraction, production, and delivery. Air pollution from gasoline and diesel is also associated with cancer, asthma, bronchitis, and other health impacts.
At a national level, oil is linked to profound national security issues, and costs drivers billions of dollars at the pump every year.
Halving U.S. oil use would help mitigate these impacts. Oil companies can also help: many emissions from oil operations can be prevented or minimized, while the dirtiest sources of oil can be avoided altogether.