Nonrenewable Resources - Fossil Fuels

Deep within our Earth's crust lies some of our most important natural resources. These resources help to heat our homes, run our cars, and maintain machinery in our major industries. As the high demand for these natural resources continues to grow, so must the realization that these resources are limited and nonrenewable.

Nonrenewable resources, like coal, petroleum, and natural gas, are those resources that are limited in quantity and cannot be replaced quickly after use. Coal, petroleum, and natural gas are produced organically and they are classified as fossil fuels. Fossil fuels form from the remains of plants and animals over millions of years. These resources also contain hydrocarbons, which are compounds of carbon and hydrogen. Stored energy collected by plants and animals from millions of years ago remains in the compounds. It's this stored energy that is released when the hydrocarbons are burned. The burning causes the bonds to break in the hydrocarbons which release heat and light. As countries have become more industrialized, humans have increased the amount of hydrocarbons that are burned, therefore increasing the amount of energy we consume. Before we get into the factors that make these resources nonrenewable, let's discuss how they are formed.

The coal deposits that exist on our planet today were formed from the remains of plants that grew millions of years ago. These remains have gone through the process of carbonization. The process begins when plants that are not fully decomposed are buried in areas that have little or no exposure to oxygen, such as swamp areas and bogs. Once the plants are buried, they become a substance called peat. While in the swamp or bog, the peat is partially consumed by bacteria. This causes methane gas, CH₄ to be released, along with carbon dioxide, CO₂. The chemical composition of the peat changes as the gases are released. Eventually, the absence of oxygen allows the first stage of coal production, carbonization, to occur. After millions of years, the peat transforms into coal.