It may look beautiful, but this oil slick threatens the environment and living things. Unfortunately, oil spills are common because we rely heavily on oil as an energy resource. Oil is an example of a nonrenewable resource.
Nonrenewable resources are natural resources that are limited in supply and cannot be replaced as quickly as they are used up. A natural resource is anything people can use that comes from nature. Energy resources are some of the most important natural resources because everything we do requires energy. Nonrenewable energy resources include fossil fuels such as oil and the radioactive element uranium.
Types of Fossil Fuels
Oil, or petroleum, is one of several fossil fuels. Fossil fuels are mixtures of hydrocarbons (compounds containing only hydrogen and carbon) that formed over millions of years from the remains of dead organisms. In addition to oil, they include coal and natural gas. Fossil fuels provide most of the energy used in the world today. They are burned in power plants to produce electrical energy, and they also fuel cars, heat homes, and supply energy for many other purposes. You can see some ways they are used in the Figure below.
Q: Why do fossil fuels have energy?
A: Fossil fuels contain stored chemical energy that came originally from the sun.
How Fossil Fuels Formed
When ancient plants underwent photosynthesis, they changed energy in sunlight to stored chemical energy in food. The plants used the food and so did the organisms that ate the plants. After the plants and other organisms died, their remains gradually changed to fossil fuels as they were covered and compressed by layers of sediments. Petroleum and natural gas formed from ocean organisms and are found together. Coal formed from giant tree ferns and other swamp plants.
Fossil Fuels and the Environment
When fossil fuels burn, they release thermal energy, water vapor, and carbon dioxide. The thermal energy can be used to generate electricity or do other work. The carbon dioxide is released into the atmosphere and is a major cause of global climate change. The burning of fossil fuels also releases many pollutants into the air. Pollutants such as sulfur dioxide form acid rain, which kills living things and damages metals, stonework, and other materials. Pollutants such as nitrogen oxides cause smog, which is harmful to human health. Tiny particles, or particulates, released when fossil fuels burn also harm human health.
The Figure below shows the amounts of pollutants released by different fossil fuels. Natural gas releases the least pollution; coal releases the most. Petroleum has the additional risk of oil spills, which may seriously damage ecosystems.
Q: Some newer models of cars and other motor vehicles can run on natural gas. Why would a natural gas vehicle be better for the environment than a vehicle that burns gasoline, which is made from oil?
A: Natural gas produces much less pollution and carbon dioxide when it burns than gasoline does. So a natural gas vehicle would contribute less to global climate change, acid rain, and air pollution that harms health. Besides being better for the environment, burning natural gas instead of gasoline results in less engine wear and provides more energy for a given amount of fuel.
Like fossil fuels, the radioactive element uranium can be used to generate electrical energy in power plants. This source of energy is known as nuclear energy. In a nuclear power plant, the nuclei of uranium atoms are split apart into smaller nuclei in the process of nuclear fission. This process releases a tremendous amount of energy from just a small amount of uranium. The total supply of uranium in the world is quite limited, however, and cannot be replaced once it is used up. That’s why nuclear energy is a nonrenewable resource. The use of nuclear energy also produces dangerous radioactive wastes. In addition, accidents at nuclear power plants have the potential to release large amounts of harmful radiation into the environment.
Q: Why is nuclear energy often considered to be “greener” than energy from fossil fuels?
A: Unlike energy from fossil fuels, nuclear energy doesn’t produce air pollution or carbon dioxide that contributes to global climate change.
- Nonrenewable resources are natural resources that are limited in supply and cannot be replaced as quickly as they are used up. Nonrenewable energy resources include fossil fuels and uranium.
- Fossil fuels—including oil, natural gas, and coal—provide most of the energy used in the world today. Burning fossil fuels produces air pollution as well as carbon dioxide that causes global climate change.
- Nuclear energy is produced by splitting the nuclei of radioactive uranium. This doesn’t release air pollution or carbon dioxide, but it does produce dangerous radioactive wastes.
- Define natural resource. What are nonrenewable natural resources?
- List four commonly used nonrenewable energy resources.
- Explain how fossil fuels formed.
- Compare and contrast the three types of fossil fuels in terms of the pollution they produce.
- Present the pros and cons of nuclear energy use.