IJISET - International Journal of Innovative Science, Engineering & Technology, Vol. 3 Issue 11, November 2016 ISSN (Online) 2348 – 7968 | Impact Factor (2015) - 4.332 www.ijiset.com 34 The Use of Tidal Energy in the World 1 Sawsan Ahmed Elhouri Ahmed & 2 Amel Abdalla Ahmed 1 University of Bahri - College of Applied & Industrial Sciences- Department of Physics- Khartoum - Sudan 2 Sudan University of Science &Technology-College of Science-Department of Physics- Khartoum- Sudan Abstract In this work we tried to summarize the use of tidal energy in the world, We also explained how these plants work and generate power. Introduction The earth surface consists of solid material and liquid (rivers, seas, and oceans) material, and it holds and attracts them by the gravity, on the other side the gravitational attraction force between the earth, the moon, and the sun perturb this material on the earth surface, as a result the solid material exposed to small deformation on its structure but clear impact in the liquid material because it's freer to move that cause the tides [1]. The attraction exerted by the moon is too larger than the attraction exerted by the sun according to the small distance between earth-moon with respect to sun-earth distance [2, 3], the earth side nearest the moon has created a bulge of water due to the gravitational force greater than the furthest side. Simultaneously, on the furthest side also bulge of water is created due to the centrifugal pull due to the rotation of the earth-moon system, As a result of the two forces; a resultant bulge is created around the earth [4] as it is illustrated in Figure (1) below: Figure (1): Tide phenomena Tides are the periodic motion of the waters of the sea due to changes in the attractive force of moon and sun upon the rotating earth [5] high tides occur when the sun and the moon are in the line known as spring tides. Conversely, neap tide occurs when the moon and the sun are orthogonal, their gravitational forces pull water in different directions causing the bulges to cancel each other. Sea level observations show that there are regular water movement on all the shore of oceans, there are two main tidal