Renewable energy sources are natural sources of energy which do not get exhausted, but are always available generation after generation. Conventional sources like coal and other fossil fuels are fast being depleted and are predicted to be completely exhausted within the next generation. As we come to grips with this likelihood, efforts are being fast tracked to promote alternative renewable sources of energy.
Known renewable sources of energy come from the environment. The sun, the wind, the earth, the tides, the rivers and some plants may provide natural renewable sources of energy. An advantage of renewable energy is most of the sources provide clean energy with no carbon monoxide or carbon dioxide emission, as found in the case of burning coal and petroleum fuels.
The sun as a source of heat and light was known to primitive man. Even today, the rays of the sun are used in rural areas for heating bath water in metal buckets. Modern technology has produced solar panels which harness the rays of the sun and convert them to electricity which can be stored in batteries or fed into electricity grids. Solar panels power a variety of appliances, including home gadgets, traffic signals and even watches.
Wind power is another renewable energy source gaining popularity rapidly. Wind is used to turn propeller turbines which produce electricity that is stored in batteries. Large wind farms in many parts of Europe such as Denmark, supply the power generated by windmills directly to the area grid. Wind farms are spreading from Europe to many other parts of the world. They work best where the wind is consistently available like seashores and high mountains.
Though the surface of the earth is relatively cool, the core of the earth is very hot. This trapped heat can be tapped into to produce energy which is called geothermal. Different types of installations have been set up to convert this energy into electricity. Operational plants of this nature are now up and running in in California, Iceland, Chile, the Philippines, Italy and New Zealand.
Tides in the ocean also give us energy by their constant motion. In this example, vanes are moved to and fro by the action of the waves. The systematic movement of these vanes drives an underwater generator to produce electricity. Commercial tidal wave farms are operating in Ireland and Portugal and another one is under construction in Scotland. The method is environment friendly and cheap to operate, though as you can imagine, expensive to initially install.
Rivers are often used to generate electric power. Fast flowing water runs a turbine that in turn produces electricity. This system is relatively inexpensive to run, and no appreciable pollution occurs.
Plants can provide renewable energy in the form of alternative fuels. The fuel is derived from the fermentation of sugar, into a form we know as ethanol. Ethanol is used as a fuel for internal combustion engines. However as a fuel, it does have disadvantages, and as it still involves the combustion process, it will still generate some pollution. So, although it is a renewable energy source, it is not a clean source.
The future of energy generation for the planet is looking cleaner and greener, with new technologies on the rise all the time so hopefully the exhaustion of fossil fuels will herald a new dawn for efficient and conscientious use of our shared resources and environment in future.