Tidal power, also known as tidal energy, is a form of renewable energy that converts the energy of tides into useful forms of power, usually – though not limited to – electricity.
By no means has tidal power reached it’s potential for usage as a source of energy. One of the benefits is that the tides are more predictable than the wind and the sun as a source. However, among the sources of renewable energies, tidal power is still relatively expensive and is limited by the geography and availability of sites that have high tidal ranges. The other factor that inhibits the growth is it is comparatively expensive to develop technically.
Recently however, there have been some technological developments and improvements, both in design and turbine technology. For instance dynamic tidal power and tidal lagoons are now capable of operation using axial turbines and cross flow turbines.
These new developments translate to a possible underestimation of tidal power as an energy source than previously assumed. As the economic and environmental costs are brought down to competitive levels, the viability of tidal power increases.
Historically Europe and the Atlantic coast of North America have used tidal mills. In Europe, this was evident from the Middle Ages, and perhaps even the Romans harvested water in this way. The simple method captured and contained incoming waters, and as the tide went out, the water turned the mills to produce a mechanical power.
However, it has only been since the 19th Century that the process of using falling water and spinning turbines has been used to create electricity. The next great advancement was when the Rance Tidal Power Station in France became the world’s first large-scale plant to become operational in 1966.
In past editions, Eco Citizen has covered some of the more recent ocean and tidal power advancements, particularly in Australia. We’ve covered Carnegie Wave Energy, Biowave Power Systems – a renewable energy technology company based in Sydney and most recently, the Sundermann Water Power Turbine.
The coast of Australia is one of several regions of the world where wave power projects are being seriously developed. Most recently Oceanlinx has begun trialling a renewable energy system at Port Kembla on the coast of New South Wales as well as shallow water variant technology (greenWAVE) on a commercial scale in South Australia.
As of July 2012, this Emerging Renewables Project undertaken by Oceanlinx will involve the grid connection of the world’s first 1MW capacity wave energy converter (WEC). This project is anticipated to take 12 months, with grid connection in late 2013.
The greenWAVE device is a rigid structure with no contaminants on board and no moving parts under water. Sitting four kilometres off the South Australian coastline with two-thirds of the structure underwater, it is extremely safe with zero emissions.