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Renewable Energy Sources

What is renewable energy? What are the different types? Get detailed information and facts on energy and its resources.

Renewable energy was once considered the future; it is now a reality. Energy transition now entails a worldwide transition away from fossil fuel use toward a low/zero-carbon future. Here in this guide, you will get all the important facts and figures and adequate knowledge of renewable energy. This guide will help you to understand all the distinct types of energy. 

Renewable energy is obtained from natural sources. These sources can replenish themselves and will not be used up sooner. While some energy sources are sustainable, others are not. Let’s take a look at them in more detail.

What is renewable energy?

It is the source of energy derived from renewable resources. Renewable sources like sunlight, wind, rain, tide, waves and thermal heat produce energy. This type of energy is also termed clean energy, generated from natural resources. It is virtually inexhaustible. While some sources of renewable energy are replenishable, others are not. For instance, some of the biomass sources are believed to be unsustainable due to the high rate of exploitation.

Now, let’s get into the details of the distinctive types of renewable resources: 

Renewable energy can be classified into Tidal Energy, Hydropower Energy, and Geothermal Energy.

Tidal Energy

Tidal power plants aim to absorb the energy of the tides as they move in and out. The key requirement for a tidal power generation site is that the mean tidal range exceeds 5 meters.

The tidal power is harnessed by constructing a reservoir by building a dam across an estuary or bay entrance. Water is initially stopped from entering the bay when the tide rises. The dam is then opened when the tides are high enough to power the turbines, and water flows through it into the reservoir (the bay), turning the turbine blades and producing electricity.

When the reservoir (the bay) is full, the dam is locked, restricting the flow, and storing the water in the reservoir. When the tide goes out (ebb tide), the water level in the reservoir is higher than the water level in the ocean. The dam is then opened to enable the turbines (which are reversible) to operate, generating electricity as the water is released from the reservoir.

Hydropower Energy

Moving water energy is one of the most commonly used green energy sources. Humans have harnessed waterpower since the Roman Empire. Water wheels were used to grind grain, saw timber, and produce textiles in the past, absorbing the kinetic energy of flowing rivers and streams. The energy of water was only transformed into electricity in the 1800s. In 1882, the world’s first hydroelectric power plant began operating in the United States along the Fox River in Appleton, Wisconsin.

Hydroelectricity, also known as hydel power, is the generation of electricity using the force of falling water. It is less expensive than either thermal or nuclear power. Dams are designed to keep water at a higher level, then released to turn turbines that produce electricity.

The basic principle behind hydropower energy is the damming of rivers to create artificial waterfalls. Sometimes, natural waterfalls are also used. Turbines that drive electrical generators are turned by falling water. One of the most significant benefits of hydropower is that it is a relatively inexpensive renewable energy source once the dam is constructed and the turbines are operational.

Geothermal Energy

The word geothermal comes from the Greek words geo (earth) and thermal (heat). Geothermal energy is a renewable energy source because heat is continuously produced inside the earth. 

Geothermal energy is heat derived within the sub-surface of the earth. Water and steam carry the geothermal energy to the earth’s surface. Depending on its characteristics, geothermal energy can be used for heating and cooling purposes or be harnessed to generate clean electricity. However, high or medium-temperature resources are needed for electricity generation, usually located near tectonically active regions.

Geothermal resources fall into three major categories:

  • Geo-pressurized zones,
  • Hot-rock zones and
  • Hydrothermal convection zones. 

Conclusion 

Renewable energy plays a vital role in today’s life. It provides energy in four major areas. These areas include water and air heating/cooling, generation of electricity, rural (off-grid) energy services, and transportation services. Globally, humans consume approximately 20% of renewable energy. It offers a progressive future for the upcoming generation. However, the implementation of Renewable energy is not an easy solution. Most renewable energy sources are sustainable. But some sources aren’t. For instance, biomass energy is believed to be a replenishable energy source. India still needs adequate infrastructure to install these energy resources densely.

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What is Renewable Energy?

Green energy and renewable technology are both associated with renewable sources, however there are some significant...Read full

What are the advantages of Tidal Energy?

The following are some of the advantages of tidal energy: ...Read full

What are the disadvantages of Tidal Energy?

The following are some of the disadvantages of tidal energy: ...Read full

Is hydropower a viable energy source?

Hydropower is a cost-effective source of electricity that is less expensive than most. Hydropower, which relies only...Read full

What is Earth's geothermal energy?

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