The sun has produced energy (solar radiation) for billions of years. This
energy can be converted into other forms of energy, such as heat and
When converted to thermal (or heat) energy, solar energy can be used
to heat water, spaces or other fluids.
Solar energy can be converted to electricity in two ways:
Wind, which is caused by the uneven heating of the Earth’s surface by the
sun, can be used to generate electricity. A wind turbine is used to collect the
wind’s kinetic energy from its blades and converts the motion of the blades to
electricity with an electric generator.
Biomass is organic material from plants or animals. When considering the
process of photosynthesis, biomass essentially contains stored energy from the
sun. When burned, the chemical energy from the biomass is converted to heat and
can be converted to electricity.
Biomass is renewable because new crops can be grown in a relatively short
period of time and they will always create waste. Examples of biomass fuels are
wood, crops, manure, and garbage.
Geothermal energy is generated from the heat from within the earth. The
heat can be moved to heat buildings or generate electricity. Heat from the
earth is constantly replenished and thus renewable. The three main uses of
geothermal energy are: direct use for heating systems, electricity generation
power plants and geothermal heat pumps.
Hydropower is energy produced from moving water. Since hydropower relies
on the earth’s water cycle to replenish the water supply, hydropower is considered
Two main sources of hydropower are the natural run of rivers and storage
systems such as a dam. Mechanical energy is harnessed from the moving water
from these sources and can turn an electric generation turbine to produce
electricity. Ocean tides and waves can also be a source of energy, however they
are not as prevalent as the use of dams and rivers.