| One of the Earth's great renewable energy sources is | | | | Tidal fences are also used to generate electricity. |
| actually the energy that can be found in all the | | | | Vertical axis turbines are mounted on fences. Passing |
| waves of the ocean. Let's look at this further. | | | | water is forced through the turbines. Ideal locations |
| If you have ever been to the ocean, you were | | | | for these are channels between two landmasses. |
| probably fascinated by the phenomena of the waves | | | | Tidal fences are cheaper than tidal barrages and |
| crashing against the shorelines as the tides came in. | | | | cause less of an environmental impact on large |
| The ocean's tides are the product of gravitational pull | | | | marine life. |
| of the sun and the moon, as well as, the Earth's | | | | Tidal turbines are a new technology used for tidal |
| rotation. It causes the ocean waters to be raised and | | | | energy. They are similar to wind turbines and are |
| lowered from time to time. The tides have cycles of | | | | arranged underwater in rows. They work best in |
| twelve and one half hours, twice per day, and are | | | | areas with strong tides. Although they are heavier |
| easily predictable. | | | | and costlier to build, they also are capable of |
| The use of tidal power is seen as early as the | | | | capturing more energy. They are also the least |
| twelfth century where tidal mills used the force of | | | | environmentally damaging of all the tidal power |
| the tides to grind grain and corn. The eighteenth | | | | technologies, since they do not interfere with |
| century brought competition from windmills and | | | | migration paths. |
| waterwheels. Tidal mills pretty much became extinct | | | | In order for tidal power to work successfully it |
| with the invention of cheap steam engines. In 1967, | | | | requires a tide difference of at least sixteen feet. |
| France became the first to be able to put tidal wave | | | | Unfortunately there are only a few places where this |
| power to work on a large scale to produce electricity. | | | | occurs. This means tidal power plants cannot just be |
| The generation of electricity from tidal waves is | | | | constructed anywhere. There are only a handful of |
| similar to that of hydroelectric power generation. | | | | sites on Earth with this type of tidal range. At |
| Bigger dams, known as barrages, are built on the | | | | present, France is the only country that has been |
| bottom of a tidal basin. Gates on the barrage allow | | | | successful in using tidal power. It is hoped |
| the tidal basin to fill during incoming high tides. | | | | developments in technology, through research, will be |
| Likewise, the basin will empty through a turbine during | | | | made to allow better use of this, what is now, |
| the outgoing tide. This would turn an electric | | | | wasted energy. The future of tidal energy seems |
| generator for the production of electricity. There are | | | | hopeful. Tidal power has great potential and hopefully |
| also systems that generate electricity from incoming | | | | we can make better use of it in the future in our |
| and outgoing tides. This system can have a negative | | | | quest to find a replacement for fossil fuels. |
| effect on plants and animals in the area. | | | | |