Article issued September 28, 2001
Energy Works
Energy comes in many different forms including heat (thermal energy), light (radiant energy), mechanical, electrical, chemical, and nuclear energy. In this thematic unit, you will find out what kinds of energy sources you use and review some ways to conserve!
Energy comes in many different forms including heat (thermal energy), light (radiant energy), mechanical, electrical, chemical, and nuclear energy. We all use at least one of these forms of energy every day. Some sources of this energy are renewable but others are nonrenewable; once they are used they are gone! In this lesson, you will find out what kinds of energy sources you use and review some ways to conserve the use of nonrenewable resources and use renewable resources.
If you look up the word "energy" in the glossary of a science book you may find a definition such as the following:
Energy is the ability to do work. It exists in many forms including heat, light, mechanical, electrical, chemical, and nuclear energy.
There are two types of energy: stored (potential) energy and working (kinetic) energy. For example, the gasoline your car uses contains chemical energy, which is stored until you release it when you start your cars engine, or make it work. There are several sources of stored energy. Some of these are renewable (meaning they can be used over and over again because they can be replaced in a short period of time) and some sources are nonrenewable (meaning that after they are used once it will take a long time for them to be replenished.)
Renewable energy sources include solar energy from the sun, wind energy, hydropower from water, and biomass energy from burning wood and organic material. In developed or highly industrialized countries such as the United States, Canada, and Japan, renewable energy supplies only about 10% of the energy needs! The energy source that is relied on most heavily (90% of the total energy demand) includes the fossil fuels-oil, natural gas, and coal-all of which are nonrenewable. In contrast, renewable energy supplies a larger portion of the energy demands of people in less developed nations, about 40%.
We use nonrenewable energy sources every day to run our cars, create electricity for our appliances, heat our homes, and to produce and package our food. Energy usage will continue to increase with the demands of our Earth's growing population needs. With such a heavy reliance on the nonrenewable resources, will this growth be sustained? Use the lessons in this unit to increase the "energy awareness" of your students and discuss ways to help to conserve our energy resources.
