Tidal barrage

A tidal barrage is a dam-like structure used to capture the energy from masses of water moving in and out of a bay or river due to tidal forces.^[1][2]

Instead of damming water on one side like a conventional dam, a tidal barrage allows water to flow into a bay or river during high tide, and releases the water during low tide. This is done by measuring the tidal flow and controlling the sluice gates at key times of the tidal cycle. Turbines are placed at these sluices to capture the energy as the water flows in and out.^[1]

Tidal barrages are among the oldest methods of tidal power generation, with tide mills being developed as early as the sixth century. In the 1960s the 1.7 megawatt Kislaya Guba Tidal Power Station in Kislaya Guba, Russia, was built. Around the same time, the 240 MW la Rance Tidal Power Station was built in Brittany, France, opened in November 1966.^[3] La Rance was the largest tidal barrage in world for 45 years, until the 254 MW Sihwa Lake Tidal Power Station was commissioned in South Korea in 2011.^[4] However, there are few other examples worldwide.