Renewable Energy: Definitions, Facts, Types, and Sources.
The Wind and solar energy are examples of Inexhaustible resources
All about Renewable Energy
Renewable energy has been hitting headlines in recent years, and it’s all thanks to mankind looking for alternative energy that is more environmentally friendly and inexhaustible. Even though it has been making so much buzz, there is still lots to be known about it.
That been said, renewable energy isn’t something new. It has been in existence since the beginning of life. Well, so we think.
In this post, you will learn about:
A brief history of renewable energy
Various definitions of renewable energy
Other names for renewable energy
Types of renewable energy
Sources of Renewable energy
Advantages and disadvantages of renewable energy
Notable renewable energy organisations in the world
Top renewable energy research centers in the world
Facts about renewable energy
Renewable Energy History
Back in the early days of mankind, when fossil, nuclear, coal and other non-renewables had not been discovered, renewable energy was the major energy option used by humans. In fact, it was the only energy option available. And they were sourced from sunlight (solar), wind (air), water (hydro), firewood and even humans.
The energy from the sunlight was used for drying and heating; the wind was used to drive windmills and also aid ship movement on water; and of course, human labour was used to do different sorts of work.
It was not until the 17th century and beyond, when non-renewables (coal, fossil, nuclear, etc.) were discovered, that the use of renewable energy began to phase out.
Then, coal and fossil fuel were perceived to serve more purposes than the available renewable energy. It had so much potential use and, with time, seemed cheaper than the already-in-use renewable energy.
Years later, questions were then raised about how cheap the
non-renewable sources of energy really are, as it was perceived to be causing
some environmental problems. Also, there were fears of running out of fossil
fuels.
So, because of the fears and unfavourable answers to questions about the challenges of non-renewable energy, scientists began to look for ways of harnessing renewable energy to its full potentials.
The scientist perceived renewable energy to be more environmentally friendly than non-renewable.
Now, the renewable-energy, that were once used menially, is now serving a lot more purpose than it used to.
Enough said! How is renewable energy defined?
Definitions of renewable energy
Renewable energy can be defined as the energy that is derived from natural sources that can timely and naturally replenish itself (e.g. wood) or can’t be exhausted at a period of time (e.g. sun, wind, etc). That is just about what renewable energy is.
However, there is no generally accepted definition for renewable energy, as there is still debate about how a certain type of energy can be considered renewable or not.
The International energy agency’s definition: “Renewable energy is the one that is derived from natural processes (e.g. sunlight and wind) that are replenished at a higher rate than they are consumed.”
The U.S. Energy Information Administration site has this to say: “renewable energy is energy from sources that are naturally replenishing but flow-limited; renewable resources are virtually inexhaustible in duration but limited in the amount of energy that is available per unit of time”
All the definitions have the same idea: Renewable energy is from natural sources and can be inexhaustible.
Non-renewable energy, on the other hand, is one that is harnessed from sources that depletes or exhausts in a human time-scale. Examples of such energy are the ones harnessed from coal, nuclear substance (e.g. uranium), fossil fuel and so on.
Renewable energy provides so much value that it is called by various names
Other Names for Renewable Energy
Over the years, renewable energy has been called various names:
Alternative energy: many do refer to renewable energy as alternative energy because it serves as an alternative option to the conventional non-renewable energy. However, some of the types of non-renewable energy (e.g. nuclear energy) are also referred to as alternative energy. How alternative energy is, all depends on an individual’s viewpoint.
Green energy: Green signifies the color of nature, life, renewal, and freshness. Because renewable energy is renewable and from natural resources, it is called green energy.
Clean energy: Renewable energy is also called clean energy because it does not pollute the environment. In contrast, non-renewable energy is also called dirty energy for obvious reasons.
Sustainable energy: It is referred to as sustainable energy because it is perceived to meet both the energy demands of today and the future.
Types of Renewable Energy
Solar Energy: This is a type of energy that comes from the sun. It is one of the most unique examples of renewable energy, as it can be transformed into electricity or heat, and exists in much abundance. The sun emits solar energy every day but does not get exhausted. In fact, the ones that are emitted every day are far less harnessed. Read more
Geothermal energy: This is the energy from the heat that is trapped within the Earth. Heat is constantly radiating from the earth’s core to the surface of the earth and the amount varies across the earth’s surface. Such heat can be transformed into usable energy to generate electricity, cool buildings and so on. However, only a few places on the earth’s surface can actually capture enough of this heat to generate electricity.
Wind Energy: Simply, energy from wind. This energy, through the use of wind turbines, can be transformed into electricity or even used for pumping water.
Biomass Energy: This is harnessed from living organic matter like plants and animals. As plants and animals die, so do fresh ones grow. So, we will never lack them. Well, at least, there is no indication that we will ever lack them. The burning of plants releases this energy in the form of heat for cooking and warming. Biomass energy also comes in the form of biofuels which can be used to run power plants or automobiles.
Hydroelectric Energy: This is harnessed from the potential energy of water at a height. This water, when released, drives a turbine which in turn drives a generator to generate electric energy.
Tidal energy: This is derived from the sudden increase or decrease in the flow of ocean water. The harnessed energy can be used to generate electricity by using some special generators.
Wave energy: It is harnessed from the waves of an ocean surface. As the ocean surface creates waves, it can be transformed into electrical energy.
Sources of Renewable Energy
Sun: This is one major source that is available over the world. It provides renewable energy in the form of solar energy. The solar energy can be used for heating, generating electricity (through the use of solar panels), and so on.
Wind: The nature of wind varies across the surface of the earth. At the right spots, it can provide wind energy which can be used to drive wind turbine to produce other types of energy (like electrical energy)
Biomass: This is basically living plants and animal organic materials like wood, food wastes, animal manure, decayed plants and so on. Energy from biomass can be used by burning directly or turning it into biofuel/biogas.
Water: This is another major source of renewable energy, as it occupies around 70% of the earth’s surface and can not be exhausted. Other sources of energy can be derived from it. For example, ocean waves, ocean tides, and so on.
Geothermal: The earth constantly emits heat from its core, and this can be converted into other forms of energy (like electrical energy)
Advantages of Renewable Energy
Clean and natural: The energy is clean because it comes from a natural source that does not pollute or damage the environment. It is because of this advantage that it also called clean energy.
Inexhaustible: Some renewable energy can not get exhausted. E.g. water, solar and so on. The sources of this energy do not cease; day after day, it keeps providing energy.
Non-monopolistic: It can not be monopolized. Renewable energy sources are spread across the surface of the earth. So, no one has exclusive control over its usage.
Different sources: Renewable energy can be derived from various sources like the sun, wind, water, etc. This helps promote diversification.
Job opportunities: With technologies been worked on, researches been made, and installations needed to help utilise the available renewable energy, a lot of new jobs are been created.
Energy independence: Now, many countries do not rely only on traditional energy sources (like fossil fuel) because renewable energy provides more energy options to choose from.
Less maintenance: Many of the renewable energy systems requires less maintenance than non-renewable ones. For example, solar power systems require little maintenance compared to thermal power systems.
Disadvantages of Renewable Energy
Less Generation capacity: Electricity generation capacity from renewable energy is far less than that of the non-renewable energy. This is due to infrastructural and technological challenges.
Less Efficient: The technology that is available to utilise renewable energy is not as efficient as that of the traditional non-renewable energy. For example, most solar panels don’t transform over 70% of the solar energy that falls on it into electrical energy.
High capital cost: The renewable energy industry is still in its infant state, and few companies are into manufacturing the technology used in harnessing such energy. So, depending on the country, if you want to invest in a renewable energy project, it will require a high initial capital. However, it is much beneficial in the long run.
Unreliability: Due to weather conditions and planetary movement, some of the renewable energy types are not available all day long. For example, solar energy isn’t available to generate electricity at night, the wind isn’t constantly blowing, and so on.
Variation based on location: The potentials of renewable energy vary across the earth’s surface. It is not every place the geothermal energy can be harnessed; the potential of solar energy is more in some countries than others; the wind is evenly distributing across the earth and so on.
Large Space needed: To generate the same amount of electricity, renewable energy (like solar) would need more space than the non-renewable energy.
Storage: Since most of the renewable energy types aren’t constantly available, there is a need to store such energy when they are available. For example, electrical energy from solar would have to be stored in a battery, to be used at night. And the cost of the batteries is quite high.
Notable Renewable Energy Organisations in the World
There are various renewable energy organisations, but here are some of the notable ones that focus on general renewable energy.
It (like the ones from sunlight, wind, wood, etc) has been in use since human existence.
Most of the harnessed energy from renewable energy sources is primarily used to produce electricity.
It is more environmentally friendly than non-renewable energy.
Even though renewable energy is serving more purpose than ever before, it can’t be fully dependent on. At least, not yet.
The energy from 1 hour of solar radiation on earth has the potential to power the world energy demand for a year or more.
It is creating a lot more jobs than the non-renewable energy industry.
The sun provides the cleanest and most abundant form of renewable energy (solar energy).
The major sources of renewable energy are the sun, wind, water (hydro), geothermal, and biomass.
Hydro is the most widely-used source of renewable energy for power generation
Key points
Renewable energy has been in use
Renewable energy can be defined as energy that easily replenishes itself and does not get exhausted in a human time-scale
Renewable energy is also called alternative, sustainable, green or clean energy
The types of renewable energy are: solar, wind, tidal, geothermal, biomass, hydroelectric, and wave energy
Renewable energy can be derived from the sun, wind, water, biomass and geothermal
Advantages of renewable energy: Inexhaustible, clean, exist in varieties, creation of job opportunities, less maintenance, etc.
Disadvantages of renewable energy: Large space needed, it can be unreliable, high capital cost, requires storage etc.
October 12, 2019 6:05 pm
Moshood Sadiq
Moshood is a Power system maintenance engineer, who has educated college students on Physics and Mathematics. He currently helps design and install solar power systems. His passion for writing is geared towards educating others on energy and electrical power systems.
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