The tidal flows and ocean currents can produce vast amounts of energy; however, we have very limited means to harness this energy. Despite high efficiency, building the plants and generating electricity has thus far proved being a costly endeavour. Despite this, there have been some commercially successful plants, as well as demonstration and testing plants that provide electricity to our grids. Here is a listing of a few of those plants.
Rance Tidal Power Station, France
Opened in 1966, this was the world’s first tidal power station. At a capacity of 240 MW, it was also the largest tidal power station in operation for 45 years until the Sihwa lake tidal station was commissioned in 2011. Sitting in the estuary of the Rance river, the 24 turbines produce approximately 500GWh per year. With costs fully recovered, the plant is able to produce very inexpensive power and compete with France’s nuclear fleet.
Jiangxia Tidal Power Station, China
Opened in 1980, the Jiangxia Tidal Power Station currently ranks as the fourth largest in the world with an installed capacity of 3.2MW. Taking advantage of an 8.39m maximum tidal range, the plant supplies energy to nearby villages together with an on-site solar generation facility.
Annapolis Royal Generating Station, Canada
The bay of Fundy is known for its great tidal ranges and draws in many tourists to see this unique feature of nature and geography. Harnessing this power has been an engineering dream that was finally realized in 1984 with a 20MW plant. With much more energy potential, it is expected that this area may see a host of other projects come online.
Uldolmok Tidal Power Station, South Korea
This 1MW plant was originally commissioned in 2009, expanded to 1.5MW in 2011, and was built at a cost of US$10 million. Still being built on, the plant’s ultimate design goal is to have 90MW of capacity installed to harness the tidal flows reaching up to 6.5 m/s in the Uldolmok Strait.
Sihwa Lake Tidal Power Station
Completed in 2011, this is currently the world’s largest tidal power plant. The tidal barrage boasts an impressive 254MW of capacity. Built in part to better regulate the water behind the seawall in which the plant sits, the plant only harnesses the inflow of tidal water, making it less efficient than other designs or plants, despite its size.