What is Renewable Energy?
In order to answer this question, we first need to ask:
What is Energy?
To a physicist, energy is defined as “the ability to do work”.
For example, as individuals, we can perform work in many ways, such as lifting an object. Machines can also perform work if they lift an object and work is also performed in numerous other was like when substances are heated.
Why is energy needed?
Energy is valuable because it allows us to perform work. It powers our bodies. It powers our homes and powers our factories. In fact, it powers our whole society. In short, we cannot exist without energy.
What form does energy take?
Energy is found all around us but is difficult to define as it comes in many different forms.
Energy Facts or Laws
The first law of thermodynamics states that Energy can neither be created nor can it be destroyed.
The second law of thermodynamics states that when you convert one energy form to another form, it is degraded.
These laws are very important to our understanding of how efficient we are at converting energy to a useable source of power.
For example, natural gas has a huge amount of energy in a very small volume which is stored in the chemical bonds that attach the carbon atom to the four hydrogen atoms of each methane molecule. When the bonds are broken, the stored chemical energy is released and light and heat are produced.
But light and heat are less concentrated or lower quality forms of energy, so the natural gas has been “degraded”.
In electrical power plants, 50% of the of the energy in natural gas is converted to electrical energy. The rest is “lost” as heat and dissipated into the environment.
Having briefly described energy and some of its properties, we can now ask:
What is Renewable Energy?
As previously stated, energy takes many forms but it can be broadly classified as either Renewable or Non-Renewable.
Non-Renewable Energy is finite. It cannot be regenerated in a timely fashion by natural process. It cannot be regenerated in a timely fashion by natural process. Examples are coal, oil, natural gas and nuclear energy.
Renewable Energy is everywhere and is continually replenished, providing a potentially enormous supply as it is generated from natural resources, such as, sunlight, wind, rain, tides, biomass and geothermal heat.
Why use Renewable Energy?
- Renewable energy sources are available year after year in steady amounts
- The technologies already exist
- The fuel is largely free
- It is clean and nonpolluting
- It is cost competitive with conventional fuels
- It is decentralised, so not vulnerable to sabotage or the control of multi nationals
- It allows you to control your own power production
Why is There so Much Interest in Renewable Energy?
Modern interest in renewable energy development is linked to concerns about the exhaustion of fossil fuels and the greenhouse gasses they create.
There are also real concerns about the environmental, social and political risks of extensive use of fossil fuels and nuclear power.
Then there are the concerns over rising fuel prices. Renewable energy is NOT subject to sharp price changes because it comes from sources such as sunshine, wind, flowing water and biological waste, all of which are FREE.
By comparrison, fossil fuels are limited in their supply and their price will only increase as they become scarcer.
The sources of alternative energy will never run out. While the supplies of fossil fuels are limited, sunshine, wind, biomass and water power are vast and are almost limitless resources.
Renewable energy is also known as Alternative Energy because it is an alternative to the use of fossil fuels to produce energy. There are real conserns that the traditional use of fossil fuels is contributing to global warmin, as the conversion process produces large quantities of CO² emissions, also known as a green house gas. Greenhouse gasses are thought to a major factor in the rise of temperature in the earths athmosphere.
For further information on the different types of Alternative or Renewable Energy, please read our other blogs.