SUSTAINABLE ENERGY SOURCES
ENERGY SOURCES
➢ These are areas of origin of particular kind of energy.
KINDS/FORMS/TYPES OF ENERGY SOURCES
a) Renewable source of energy
Examples: Sun, Water, Wind, Sea waves.
b) Non – renewable source of energy
Examples: Oil and natural gases, because once used, they cannot be replenished.
SUSTAINABLE ENERGY SOURCES
➢ These are natural sources that are used in the production of electricity without destroying the
environment.
These sources occur naturally and are readily available.
Sustainable sources of energy include the following:
1. Hydroelectric energy (water energy)
2. Solar energy
3. Wind energy
4. Sea wave energy
5. Geothermal energy
6. Tidal energy
1. HYDROELECTRIC ENERGY (WATER ENERGY)
➢ This is used more than any other renewable source for producing electricity.
❖ Here, the source of energy is water. Hydroelectric power (HEP) stations provide about 20% of the world’s electricity.
GENERATION OF ELECTRICITY FROM WATER
As water flows into a dam, it turns turbines and generators to produce hydroelectric power.
The dam is made much thicker at the bottom than at the top in order to withstand the pressure.
The pressure of water increases with depth and is therefore greater at the bottom. Only thick walls can withstand this pressure.
IMPORTANCES/ADVANTANGES/CHARACTERISTICS OF WATER ENERGY
➢ The energy is virtually available. Water flows freely from various sources. Examples; Mountains and rivers.
➢ It is environmental friendly since no waste or pollution is produced.
➢ It is more reliable than other sources.
➢ It increases power very quickly.
➢ Electricity can be generated constantly since there is a constant flow of water.
1 APPLICATIONS OF WATER ENERGY
Energy from water has the following applications
1. INDUSTRIES
➢ Electricity is used in industries to drive machines that in turn help in manufacturing of goods.
2. LIGHTING PURPOSES
➢ For example in homes, schools, hospitals and offices
3. HEATING AND COOKING
➢ Electric heaters and cookers use electricity. This forms an efficient way of cooking.
4. IN HEALTH FACILITIES
➢ Electricity is used to maintain some medical processes. For example running incubators and
freezers
DISADVANTAGES OF WATER ENERGY
➢ Dam can be expensive to build and need large area of land.
➢ Hydroelectric schemes flood large areas of land hence affecting the ecology of the area.
➢ Energy produced is wasted on the way as heat since it is transmitted using metallic power
lines.
2. SOLAR ENERGY
➢ This is the energy from the sun.
❖ Solar energy is obtained from the sun using solar cells which turn it into electricity.
❖ Solar energy can be converted to electricity by using solar cells (photovoltaic or photoelectric cells).
❖ The main surface of a solar panel is dull black. This enhances the absorption rate of radiant energy from the sun. It is also covered with glass. The back of the solar panel is normally insulated.
The pipes in the solar panel are bend or coiled and are made of copper or plastic. Coiling the pipes increases the surface area over which the radiant energy can act. Water moves through these pipes.
APPLICATIONS OF SOLAR ENERGY
➢ Lighting purpose
➢ Heating water
➢ Powering spaceships and satellites.
➢ Powering calculators and torches
➢ Drying clothes and farm products by the availability of the sun.
➢ Provision of electricity used by electrical appliances such as radios and televisions.
3. WIND ENERGY
➢ This is the energy comes from the sunlight.
❖ When the sun heats the earth (atmosphere) unequally, some patches become warmer than others.
Warmer patches of air rise, cold air blows in to replace them and hence we feel a wind blowing.
