Renewable energy is a type of energy that comes from sources that are naturally replenished after they have been used. When fossil fuels, which are not renewable, are burned to create power, they cannot be replaced. They have formed over millions of years through geological processes that are no longer producing more fossil fuels. Once they have been used, they have been consumed.
Renewable sources of energy are constantly replenished. The wind continues to blow, the sun continues to shine and water can be turned into hydro-energy. When these types of energy are used to produce power, they are not consumed. They can continue to be used.
Renewable energy can be used commercially, but it can also be used on a small scale, to produce energy for a single home or for a small community.
The energy that is produced from renewable sources currently makes up approximately 19 percent to the total amount of energy that is consumed worldwide (even though countries like Australia are trying to change that at a huge speed!). Most of this renewable energy is produced through traditional use of biomass. Wood and other types of biomass are still the main source of heat for warmth and cooking in many parts of the world. Hydroelectricity is another common form of renewable energy. It is the main source of electricity, rather than energy including heating, derived from a renewable source. Other sources of renewable energy include solar power, wind power, electricity generation from biomass, geothermal power and biofuels.
The use of renewable energy is growing rapidly as the demand for cleaner sources of electricity grows and as the technology is improved. New renewables, which include biofuels, solar power and wind power used for electricity production or as renewable fuels are growing particularly fast.
Renewable energy has huge potential because there is a vast amount of energy from renewable sources that are not currently being used. Some countries, such as Paraguay, which produces all of its electricity through hydroelectric power, and Denmark, which produces 20 percent of its electricity through wind power, have already begun to rely heavily on renewable power. Many other countries have also begun to implement large-scale renewable energy production, but there are still parts of the world where renewable energy production is seldom used.
The main advantages of renewable energy are that it generally produces little pollution and that the sources of power will never be depleted. Renewable power can usually be produced reasonably cheaply, although the start up costs can be very high.
Criticisms of renewable energy usually focus on the fact that power can only be produced intermittently. Solar power cannot be produced during the night, for example, and wind power can only be exploited when the wind is blowing. This means that it is not usually possible to rely on a single source of renewable energy. Different types of power need to be combined in order to ensure a steady supply of electricity. Energy from renewable power sources can also be stored, in batteries, by using it to create hydrogen fuel, or through hydroelectric storage, in order to provide electricity during times when it cannot be produced.
The intermittent nature of some renewable energy sources can be compared to the fluctuations in the availability and prices of fossil fuels, with which traditional power plants have to cope. Although the amount of power that can be produced from a renewable source can vary, it is usually available at no cost and it will never run out.
The advantages and disadvantages of using renewable energy, and the potential which it presents for energy production, depend upon the source of power and the means through which it is being harnessed. Using geothermal power for small-scale energy production is very different from using solar power for commercial electricity production. Renewable Energy is good for the environment with current climate changes. PennEnergy.org is an informative website where it is possible to learn more about the use of renewable energy.