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Fossil FuelsThere are three main types of this non-renewable energy source: coal, oil, and natural gas. These are called fossil fuels because they were formed millions of years ago. The energy originally came from the Sun and was stored as potential energy by photosynthesis in plants and tiny organisms such as algae and plankton. Bacteria and the pressure of the Earth on these remains converted the living organisms into coal, oil, and natural gas.Coal was the first fossil fuel to be used on a large scale. It can be burned to provide heat. If coal is heated in a closed container without burning, it produces a gas that can be used as fuel. This coal gas is similar to natural gas and was used to supply energy to homes during the 19th and part of the 20th century. When fossil fuels are burned to create energy, they release harmful gases that pollute our air, soil, water. Today, more than three-quarters of all power used in the United States is produced from fossil fuels. In just a thousand years we have mined much of the planet's supply of coal. Oil and gas were discovered less than two hundred years ago, but experts believe we will begin to run out of these fuels within two hundred years. |
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