For comparison, production of power from river dams typically averages 70-100 percent of installed capacity. The average output of tidal electricity is less than 40 percent of the installed generating capacity. The machinery also must withstand the rigours of saltwater operation.įor all this investment, the average electric power output is severely limited by the twice-daily ebb and flow of tides. Because of this, many machines are needed to produce a significant block of power. The relatively low head of water above the turbines restricts the capacity of individual generators to about 25-50 megawatts (MW). This reduces the amount of coal and oil used, and substantially reduces the production of their associated pollutants. The output from conventional fossil-fueled generating stations can be reduced when the tidal plant begins generation, and it can be brought back into the system during the few hours that a tidal plant must remain idle. Large, modern power systems can readily absorb the intermittent output of a tidal plant. Using new technology, turbines can be built to generate electricity in both directions, and also to operate as pumps in both directions. These cycles take place about twice a day (two flood tides and two ebb tides during each lunar day). When the tide begins to turn and the sea level rises, the sluiceways are opened once more, so that the tidal basin can be filled for the next cycle of electrical generation. When this difference becomes large enough, flow is allowed through the tidal generators until the difference in levels becomes too low to drive the turbines. The sluiceways, artificial channels with gates, close at high tide and the ebbing sea level causes a differential head between the basin level and the sea. One of the most practical ways to harness tidal energy is still the old tide mill concept: closing off an estuary or tidal basin from the sea with a structure composed of a powerhouse, a sluiceway and a solid embankment section. With the world’s highest tides occurring in the Bay of Fundy, there is additional opportunity for large-scale tidal energy projects in Canada.

North America’s only tidal energy plant is located at Annapolis Royal, Nova Scotia. While the potential of tidal hydroelectricity has long been recognized, compared to river dams, tidal power projects are expensive because massive structures must be built in difficult saltwater environments. Tidal energy is the sun and moon’s influence over the ocean.Tidal energy is a largely untapped, renewable energy source based largely on lunar gravitation. Gravitational and centrifugal forces are the two forces that rise the tides.įinally, on the definition of tidal energy, it is a form of hydropower that converts the energy obtained from tides into other useful energy (electricity). Tides are long-period waves that occur in an ocean, which are caused by the combined gravitational effects of the sun, the moon, and the rotation of the earth. Likewise, when the moon and earth’s gravitational field are perpendicular to each other, their influence becomes weak, causing the water to flow away from the shore resulting in a low tide condition. When the earth and moon’s gravitational field are in a straight line, the influences of these two fields become stronger causing millions of gallons of water to flow towards the shore resulting in high tide conditions. It is known as high tide when the sea level rise and it’s called low tide when the sea level falls. At a particular place, tides usually occur twice on a lunar day. The alternate rise and fall of the sea levels are caused by the gravitational forces of the sun and moon and the evolvement of the earth. For clarification, you should understand the term ‘tides’ It can also be said to be renewable energy in which tidal action in an ocean is converted to electric power. It relies on the rising and falling of sea levels and tidal energy devices convert the energy gained from tides into electricity. Tidal energy or tidal power is a form of hydropower that is harnessed by converting tide energy into useful forms of power.

Tidal power plant