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What is Tidal Power

Tidal Power, often referred to as tidal Energy, is achieved through the capture of the energy created as water moves in ocean currents and tides. Two types of tidal power can be harnessed for energy-efficient power. The first is called kinetic energy. This is tidal energy directly created as the water is moving in rivers and in oceans as tides. The tidal power that requires one more step, called potential energy, comes from the difference between low and hide tide height. This height is commonly referred to as head.

The kinetic tidal power process uses turbines to produce the renewable energy. To understand this process think of windmills and visualize them underwater this is the means for kinetic tidal power. It is becoming increasingly more popular because its impact on our ecology is so much less dramatic than the building of dams, or what some refer to as tidal fences or barrages. The United States and other countries across the globe are studying their coastal areas with an eye for the suitability of the region for the production of kinetic tidal power. The ideal of these have high speeds of the water that occurs in the local channels as they enter the river or bay. Water currents in rivers that run between islands are especially good for tidal energy as the currents there are highly concentrated and often quite powerful.

Tidal energy, with Solar and wind energy, are one of the most popular and well-touted of the sources of renewable energy. This is because ocean tides especially are caused by the orbit of our solar system. Ocean currents, as part of this process, happen because of the way winds are affected on the earths surface. This tidal power supply is, thus, deemed inexhaustible. The primary energy source here is the kinetic energy produced by the orbit of the system of earth and moon, and earth and sun. Tidal power has an excellent potential as a future source of the generation of Electricity because the energy generated by these galactic rotations will continue unabated forever - or so scientists believe. Tidal power is not something new, however. European tidal mills have been a part of grain grinding operations for almost one thousand years.

How efficient tidal ocean dam power is depends on the height of the tidal swells rise and fall. This is commonly referred to as amplitude. This amplitude can be as high as 33 feet 10 meters. This occurs where the tidal waves are funnelled into fjords or rivers and water velocity is extreme. The speed of the water might be as fast as 16 knots. One example of this is Vancouver Island in Canada. Even greater amplitude is experiences in the Bay of Fundy, where the amplitude might reach 56 feet 17 meters. This is because the tides resonance amplifies the ocean waves.

Thus, we see that the selection of the right location for a tidal power generator is crucial to its success as an efficient source of Green energy.

How it works

Experts have been attempting to harness the power of the wave since the late 19th century. As the wind passes over the ocean, it produces waves. There is a direct correlation between the power of the wind and the power of the wave.

Wave energy is produced when electricity generators are placed on the surface of the ocean. The energy provided is most often used in desalination plants, power plants and water pumps. Energy output is determined by wave height, wave speed, wavelength, and water density. To date there are only a handful of experimental wave generator plants in operation around the world.

The Aguadora Wave Park (AWP) in Portugal is the worlds first commercial wave farm. The AWP produces roughly 2.25 Mega-Watts of power (enough for 1500 homes) and cost just over 8.5 million euros to deploy (though by 2009 costs are expected to exceed 70 million euros).

Construction and Maintenance

Most turbines require a constant, powerful flow which works in opposition to the very nature of waves, as waves are inconsistent in both direction and power. Powerful storms and the corrosive power of salt water are also adversarial to the construction of a reliable energy collection device. Accounting for the aforementioned problems, a device and its maintenance may become too expensive to be a reliable Alternative to coal, oil, BioDiesel or even solar power.

Harnessing the Waves

Wave energy collection is, however, remarkably passive. Unlike oil which requires a distillation process before energy can be used, wave energy is automatically converted by turbines. Wave energy is also environmentally friendly, as it creates no atmospheric pollution and has a small carbon footprint (non-existent if not for the manufacture of its devices). More-so, it allows us to utilize a space which has, for most of history, been underutilized: the ocean.

The flowing waters in the rivers and tidal waves can be a good source of alternative energy. With 70% of the earth's surface covered with water, a great amount of energy can be produced by placing turbines at strategic locations under strong currents. This method of generating electric power is called hydrokinetic power generation.

The Future of Wave Power

According to Trey Taylor Co founder & president of Verdant Power, 4 commercial projects are planned for the next 3-5 years which should have the capacity to produce more than 200 MW when operating in waterways. As great minds continue to tackle the problems of renewable energy, we may see major advancements making wave energy more feasible. Groups such as OREC (Ocean Renewable Energy Coalition), continue to drum up support for projects, but it seems policy makers are a bit uncertain of wave energy's true benefits.

For now we should focus on implementing wind power and solar power strategies to replace our dependence on oil. It may seem like a panacea on paper, but the reality exposes the truth, wave power is just not ready for wide-scale commercial use yet.