Which tidal barrage in France began generating electricity in 1966 and was then the world's largest tidal power station?

The Rance Tidal Power Station in France began generating electricity in 1966 and was then the world's largest tidal power station.

The facility is built across the Rance estuary in Brittany, where the difference between high and low tide creates a strong flow of seawater. Its 24 bulb turbines can generate electricity as water moves in and out of the impounded basin. The station has an installed capacity of 240 megawatts.

Construction took several years and required a barrage, or dam-like barrier, across the estuary. Unlike a tidal-stream project, which places turbines directly in moving ocean currents, a tidal barrage uses a difference in water level created by the barrier. This distinction explains why Rance is not classified as a tidal-stream station.

Rance held the tidal-power capacity record for decades. South Korea's Sihwa Lake Tidal Power Station later exceeded it. Rance remains an important demonstration that predictable tides can provide renewable electricity, although estuary projects can affect habitats and sediment movement.