OPERATING TIDAL BARRAGE POWER PLANTS
Harnessing tidal motion to generate mechanical power has a long history. Tidal basins were being used in Europe to drive mills to grind grain before 1100 AD. These plants were widely replaced when the Industrial Revolution introduced steam engines and fossil fuel, but a few survived though there are none now operating commercially. The exploitation of tidal ebb and flow to generate electricity has been less well tried. Table 9.1 shows the most important tidal power plants that have been built. As the table indicates, the largest is at Sihwa in South Korea, followed closely by La Rance on the northwest coast of France close to St. Malo.
The 240 MW La Rance plant was built using specially devised bulb turbines. A small turbine of similar design was bought by the Russian government during the 1960s, but it is not known whether it was ever deployed, although there has been speculation that the 400 kW Kislaya Guba project represents the final resting place for that turbine.
After La Rance, the third largest tidal barrage project is at Annapolis Royal on the Bay of Fundy in Canada. China has also developed some small-scale pro- jects, of which the largest is at Jiangxia. Work on tidal power generation began in China in 1958 and there are thought to be seven projects in operation today with an aggregate capacity of 11 MW.