Tidal giants the world s five biggest tidal power plants· La Rance Tidal Power Plant France 240MW The 240MW La Rance tidal power plant on the estuary of the Rance River in Brittany France has been operational since 1966 making it the world s oldest and second biggest tidal power station The renewable power plant currently operated by Électricité de France EDF has an annual generation capacity of 540GWh The La Rance tidal power