Types of Renewable Resources and their Purpose

Renewable energy resources are natural resources that replenish themselves within time limits that permit sustained use, in contrast to nonrenewable resources. That is, resources can be replenished by natural process at least as fast as they are used. Therefore it can be used over and over again. Five types of renewable resources are: Wind Power, Hydropower, Solar Energy, Geothermal Energy, Biomass Fuel and Wood.

Hydropower
Hydropower is the capture of the energy of moving water (falling of water from one level to another) for some useful purpose. This falling of water can be natural falling source or from a dam. The falling water is used to turn waterwheels or modern turbine blades which is used to powering a generator to produce electricity. Hydropower system is a clean source of energy systems that can neither be polluted or consumed during its operation. It eliminates the cost of fuel, making it immune to price increases for fossil fuels. As long there is a water source (lake, river etc.) it is renewable.

Solar Energy
Solar energy is the energy from the sun ( in the form of heat and light) that is directly capture and converted into thermal or electrical energy and harnessed as solar power. Solar power is the technology of obtaining (harnessing) usable energy from the light of the sun. Some applications of solar energy are hot water heating and space heating in the home. It is also used in the application of solar panels where individual homes (in region where it is warm and sunny) convert solar energy into thermal energy to generate electricity.

The use of solar energy displaces conventional energy where it results in a proportional decrease in green house gas emissions. The energy from the sun is free with just the initial cost to set up the technology. The sun provides unlimited (renewable) supply of solar energy. The only draw back is that its requires a large area to collect the sun’s radiation and requires some means of storage.

Wind Power
Wind power is the conversion of wind energy into electricity using wind turbines (usually mounted on a tower). Wind power is used in large scale wind farms for national electrical grids. On a small scale it is also used to provide electricity to rural residences. Wind energy is ample, free, widely available, clean, renewable, produces no waste or greenhouse gases, need no fuel, good method of supplying energy to remote areas and can be a site for tourist attraction.

Biomass Fuel
Biomass Fuel (Biofuels) is any organic material produced by living organisms (plants, animals, or microorganisms) that can be burned directly as a heat source or converted into a liquid or gas. Some examples of biomass fuels are wood, crop residues, peat, manure, leaves, animal materials and other plant material.

There are two major sources of biomass;
i. trees, gains, sugar crops and oil-bearing plants.
ii. waste organic materials from industrial, commercial, domestic, or agricultural wastes. Examples, crop residues, animal wastes, garbage, and human sewage.

Biomass fuels (biofuels) are sustainable. It is cheap and is less demanding on the environment or Earth's resources. A major advantage of biomass fuel, is its low greenhouse gas emission characteristic where it adds less carbon to the environment when compared with burning fossil fuels. This is due to the fact that the carbon atoms released by burning biofuel already exists as part of the carbon cycle. Biomass absorbs an equal amount of carbon in growing as it releases when consumed as a fuel.

Fuel diversity is another advantage of biomass, it can be transformed into fuel in many ways such as in gasification, anaerobic digestion - fermentation of wet wastes (e.g. sugarcane or corn to produce alcohol (ethanol) and esters, and animal dung to produce biogas) and direct combustion - burning of dry organic wastes (e.g. wood and peat) just to name a few.

The use of biomass fuels can reduce dependence on foreign sources of oil whereby providing energy security for the country using it as a fuel. This will therefore promote an economic boost for both agriculture and the industry of that country. However, for it to be economical as a fuel for electricity, the source of biomass must be located near to where it is used for power generation.

Geothermal Energy
Geothermal Energy is power generated by the harnessing of heat from the interior of the earth when it comes to (or close to) the earth’s surface. The regions with highest underground temperatures are in areas with active or geologically young volcanoes. Chief energy resources are hot dry rock, magma (molten rock), hydrothermal (water/steam from geysers and fissures) and geo-pressure (methane-saturated water under tremendous pressure at great depths).

There are several methods of deriving energy from the earth’s heat where the heat energy that is generated by converting hot water or steam from deep beneath the Earth’s surface is converted into electricity. This hot water or steam come from a mile or more beneath the earth surface. geothermal applications includes:

i. Geothermal Electricity Production - generating electricity from the earth's heat. The steam rotates a turbine that activates a generator, which produces electricity.
ii. Geothermal Direct Use - Producing heat directly from hot water within the earth.
iii. Geothermal Heat Pumps - Using the shallow ground to heat and cool buildings.

Related Articles:
The Effects of Global Warming
Sustainable Development - Its Meaning and Purpose