Tidal energy is energy that could be obtained from the changing sea levels. In other words, tidal energy is a direct result of tide shifting from low to high.

Tidal energy is considered to be a renewable source of energy since it only uses the energy from the changing of the tides instead of burning or consuming any form of energy source. It is also considered to be inexhaustible because tides always rise and fall due to gravity.

Tidal power utilization is also considered to be a very reliable source of energy due to its predictability. Compared to other sources of energy such as wind or solar energy, tidal changes are easier to predict. They’re also sure to occur consistently. Unlike solar or wind energy, tidal power does not depend on the season or the weather type. Instead, tidal energy relies purely on the orbital kinetic energy that the sun exerts as the earth orbits around it. The same goes with the moon and earth orbital system. As the moon orbits around the earth, a gravitational force is experienced by both bodies.

Consequently, all of the forces that work within the orbital systems create an imbalance in the earth’s water levels. Thus, some places have higher water levels while other places have decreased water levels.

How Tidal Energy Works

Water could be trapped or held within specially made structures during high tide. A water containment reservoir called a tidal lagoon is constructed. The lagoon is filled with water as the tide goes up the reservoir.

As the tide shifts from high to low, there exists a difference in pressure between the water in the higher containment structure and that in the open water source. This will form a head pressure (also known as hydrostatic pressure) on the containment structure. The difference in water levels between the open water source and of the contained water will result to potential energy which could be utilized when the contained water is released.

When the natural body of water (water outside the containment) reaches a very low level due to the low tide, the water within the reservoir is released using specially made outlets that are usually equipped with turbines. The force of the rushing water would spin the turbines which would in turn power generators that would produce electricity.

Potential energy increases as height is increased. More energy is stored by an object as it goes higher and higher. This potential energy could then be released and then converted into electricity through the use of proper devices and modern technology. Tidal energy would be most effective and economical to produce, therefore, if water levels between tides are significant.

Benefits of Tidal Energy

The key benefit of tidal power is that once constructed, it’s free. It does not generate any unsafe greenhouse gases or hazardous waste. It functions without any fuel requirement, only with natural tidal energy. It is a consistent source of electricity with very little maintenance cost. Offshore turbines and vertical-axis turbines are economical to construct and do not have a big ecological effect.

Limitations of Tidal Energy

Tidal energy could only be harnessed in places with significant water level changes. The conversion of the potential energy that the tides will hold shows figures that are more or less 80%. This means that 20% of total potential energy is usually lost and only 80% of potential energy is typically utilized for electricity generation.

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