Oil is the largest source of energy in the United States, providing close to 40 percent of all of the nation’s entire power needs.
Though most oil is used for transportation or home heating purposes, a small percentage is still used as a fuel for electricity generating plants.
While oil continues to decline in popularity as an electricity fuel, in places such as New York, oil still comprises about 8 percent of the state’s electricity fuel mix.
Oil sits in deep underground reservoirs. Like other fossil fuels, this liquid is the end-product of millions of years of decomposition of organic materials. Since the ultimate amount of oil is finite — and cannot be replenished once it is extracted and burned – it cannot be considered a renewable resource, like wind power.
Once extracted, oil can be refined into a number of fuel products — gasoline, kerosene, liquefied petroleum gas (such as propane), distillates (diesel and jet fuels) and “residuals” that include industrial and electricity fuels. Three technologies are used to convert oil into electricity:
- Conventional steam – Oil is burned to heat water to create steam to generate electricity.
- Combustion turbine – Oil is burned under pressure to produce hot exhaust gases which spin a turbine to generate electricity.
- Combined-cycle technology – Oil is first combusted in a combustion turbine, using the heated exhaust gases to generate electricity. After these exhaust gases are recovered, they heat water in a boiler, creating steam to drive a second turbine.
What Are the Environmental Impacts?
Burning oil to generate electricity produces significant air pollution in the forms of nitrogen oxides, and, depending on the sulfur content of the oil, sulfur dioxide and particulates. Carbon dioxide and methane (as well as other greenhouse gases), heavy metals such as mercury, and volatile organic compounds (which contribute to ground-level ozone) all can come out of the smoke stack of an oil-burning power plant.
The operation of oil-fired power plants also impacts water, land use and solid waste disposal. Similar to the operations of other conventional steam technologies, oil-fired conventional steam plants require large amounts of water for steam and cooling, and can negatively impact local water resources and aquatic habitats.
Sludges and oil residues that are not consumed during combustion became a sold waste burden and contain toxic and hazardous wastes. Drilling also produces a long list of air pollutants, toxic and hazardous materials, and emissions of hydrogen sulfide, a highly flammable and toxic gas.
All of these emissions can impact the health and safety of workers and wildlife. Loss of huge stretches of wildlife habitat also occur during drilling. Refineries, too, spew pollution into the air, water and land (in the form of hazardous wastes). Oil transportation accidents can result in catastrophic damage killing thousands of fish, birds, other wildlife, plants and soil.