# Wave Power

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## How Are Waves Formed?

We have seen that waves form in the ocean, and they hit the shore with a large force and a loud noise.

These waves originate in the ocean and destroy on the shore.

So, what makes these waves?

Wind energy transfers its energy to the surface water of the ocean, and hence waves are formed.

The formation of the waves is an endless phenomenon, so they keep on forming in the ocean and keep on destroying on the shore.

These waves have enormous potential.

It is calculated that if the potential of these waves is completely exploited then, they can fulfill 40% of the world’s total energy needs.

The advantage of wave energy is that it is an incessant source of energy.

### What is Wave Energy?

Wave energy is one of the forms of the ocean or sea wave energy.

Unequal solar heating of the earth generates wind and wind blowing over the surface of water generates waves.

So, the energy possessed by the ocean and sea waves is called the wave energy.

### The Advantages of the Wave Energy Are

1. Non-polluting

2. Renewable source of energy

1. Variable output

2. Affects marine life

3. Expensive

### Ocean Wave Energy

The water of the oceans of the world is almost always in motion. The uninterrupted waves breaking at the coastlines are sometimes strong and sometimes weaker.

These waves have tremendous potential energy round the clock and are free-of-charge.

If the potential of these waves is fully utilized. They can satisfy 40% of the worldwide power demand and this output is equal to 700 to 800 nuclear power stations.

The point hydroelectric chain is developing technologies to transform this inexhaustible into electric power without the emission of the harmful greenhouse gases.

### Wave Energy System

Wave energy stems from wave motion and its power is related to the wave height and period.

Deep-water sea waves generate large energy fluxes under predictable conditions over the periods of days.

The power is given by:

P = (1/64)(ρg2/π)(Hs^2Te^2)

Here, P = Power per unit width of a wavefront measured in W/m

ρ = Density of seawater in Kgm-3,

g = Acceleration due to gravity in ms-2,

Hs =The significant wave height in m, and

Te = The wave period in s-1.

### What is Wave Power?

Let’s understand how we can generate electricity from the ocean waves.

Let’s talk about the wave power station, its principle, and working on how to generate power.

The principle of a wave power station is pretty simple.

An enclosed chamber has an opening underground sea level that allows water to flow from the sea to the chamber and back.

The water level in the chamber rises and descends with the rhythm of the wave.

The air is pushed forward and backward through the turbine connected to the upper opening in the chamber.

As this turbine is compressed and decompressed, the airflow has sufficient power to run the Wells turbine.

It is an attribute of Wells turbine (named after its inventor Prof. Alan Arthur Wells) that if it is driven in the same direction by both forward and backward airflow through the turbine.

Even the weaker airflow can produce sufficient airflow that can keep the turbine rotating, and to generate energy.

As long as there are waves, we can get electrical energy from the wave power station anytime.

The world’s first commercial wave power station was activated on the Hebridean island of Islay and has been feeding power to the grid ever since.

India’s first wave power station named Vizhinjam wave energy plant (located at Vizhinjam, the city in Thiruvananthapuram, Kerala) was set up in 1991.

It is the world’s first wave power plant that works on the Oscillating Water Column (OWC) technology.

Power plant working on OWC technology

### Examples of Wave Energy

Wave energy is also known as the Ocean energy or sea wave energy which is harnessed from the ocean or sea waves.

The rigorous vertical movement of surface ocean currents comprises a lot of kinetic energy that is captured by wave energy technology to do needful tasks.

The captured energy is used to fulfill various tasks such as:

1. Generation of electricity

2. Desalination of water, and

3. Powering the plants or pumping of water into reservoirs.

### Example of Wave Energy Conversion

The wave energy is converted into power or wave power and a machine that makes the most use of wave power is a Wave Energy Convertor or simply WEC.

This Wave power captures the energy of wind waves to do useful works such as electricity generation or pumping the water.

Such an example of WEC is Wind Activated Bodies or WAB. They are very compact and light-weighted.

### Here Are Some Examples of Wave Energy Conversions

1. Ocean wave energy conversion

2. Resonant wave energy conversion

3. Buoy-type wave energy conversion

1. What is Wave Power and How Does it Work?

Wave power is generated by the up and down movement of floating devices placed on the surface of the ocean as you can see below:

Wave energy Convertor

Generally, wind produces waves, and then waves produce energy.

As the waves traverse the ocean, high-tech devices like the wave energy converters capture the natural movements of ocean currents and the flow of swells to generate power.

2. Why is Wave Energy Important?

One of the benefits of using wave energy is that it is environment-friendly because the devices generating power don’t emit harmful gases.

The energy produced from these waves goes directly into the electricity-generating devices and is used to power generators and power plants nearby.

3. How Much Power Does Wave Energy Produce?

The kinetic energy produced by the motion of waves is tremendous and mighty, that on an average, just in 10 seconds. The wave on striking with a coast puts out more than 35,000 horsepower.

4. How Reliable is Wave Energy?

Wave energy is reliable energy that doesn’t emit harmful gases like greenhouse gases and reduces our dependence on fossil fuels.