How tidal works: Overview

Tidal energy is the world's most predictable renewable energy source and with increasing demands on the earth's natural resources, it offers a reliable and sustainable opportunity for energy generation.

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Tidal energy is produced by extracting the kinetic energy contained in flowing water brought about by the changing tides to turn a turbine to generate power.

Tides are the rise and fall of sea levels, determined by the position of the moon and the sun and their gravitational pulls on the earth. There are generally two high and two low tides per day, but in some areas, there may only be one of each. Factors that can impact on the scale of tides include the underwater landscape, water depths and the surrounding coastline.

Converting the power of the tides into energy is not a new thing; we have been using water to generate energy since Roman times through tide mills.

Today, tidal technology is developing rapidly, although the principle behind the different types of technologies is the same. Tidal plants, whether they are tidal turbines, tidal fences or tidal barrages, utilise the flow of water to turn a turbine to generate electricity.

Although generation does not take place 24 hours a day, tides rise and fall every day and can be reliably mapped many years in advance, making tidal energy a stable and predictable method of energy generation.

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