Tidal energy, also referred to as tidal power, is a process that harnesses the energy of the tides and converts it into power. Tidal energy is far more predictable than other forms of clean , green , renewable energy such as solar, wind and wave energy. In fact, tidal energy is far from being a new concept and has been used throughout history as a source of energy. The earliest account of tidal energy use dates back through the Middle Ages to Roman times!
How do the tides work? Basically, the relationship between the Earth and moon causes the tide to change. As the moon rotates around Earth and the Earth rotates around the sun, it has a gravitational push and pull on the ocean. This fluctuation takes energy, and that is the energy that can be harnessed! Because this process of fluctuating tides occurs at fairly predictable intervals of time, and because it is likely that the tidal fluctuations will continue to occur indefinitely, tidal energy is viewed as an inexhaustible resource.
There are several tidal energy farms throughout the world. Two farms are currently being built in Wales and both are expected to be operational in 2010. In Canada, the British Columbia Tidal Energy Corporation is currently building three turbines in Campbell River and should be completed by the end of 2009. Nova Scotia is also building a tidal energy farm.
Tidal energy power, like solar power, has a high initial investment and a very low maintenance cost. This poses a challenge, however, because many investors aren’t willing to provide the initial investment, especially when returns come back over an extended period of time. However, tidal energy has the potential to replace fossil fuel power plants. For example, a proposal for a tidal energy plant for the Severn Barrage in the United Kingdom would prevent eighteen-million tons of coal each year from being used.
There are many additional benefits to investing in tidal energy. To start, tidal energy farms can be located in any body of water that is affected by tidal fluctuation—oceans and rivers connected to the ocean. It is also very consistent, which is a problem that other sources of clean, sustainable energy sources face.
Harnessing tidal energy is a very interesting idea. Tidal energy advocates are highly optimistic and see the potential for tidal energy to provide a large amount of the energy. Opponents to the idea of tidal energy mainly point out its initial investment, which like solar power, is very high. However, many people are able to see beyond this challenge. After all, most environmentalists easily understand the concept of investing in compact fluorescent light (CFL) bulbs, even though they are more expensive than incandescent bulbs.
We need to keep in mind that when the use of fossil fuels began, it was extremely expensive to build the power plants and create the energy grids necessary to transfer that energy. More than one hundred years later, the process of obtaining energy from fossil fuels has been streamlined. EnviroCitizen.org acknowledges that it may be more expensive to invest in tidal energy now, but notes that in the not-too-distant-future we will be able to enjoy a low-cost, highly renewable, very green, clean energy source that with further preserve the Earth! An upfront investment is certainly worth the long-term benefits the Earth with experience.