Tidal Barrages

The simplest generation system for tidal plants involves a dam, known as a barrage, across an inlet. This produces energy similar to a dammed river, where the water level is higher on one side of a tidal barrier than it is on the other side.

Sluice gates on the barrage allow water to flow through turbines that generate electricity. The sluice gates allow the tidal basin to fill on the incoming high tides and to empty through the turbine system on the outgoing tide. Each time, water passes through the barrage, the turbine spins and electricity is generated. As a result of the tidal cycles, there are four main times during each day that power is generated most effectively during incoming and outgoing tides.

There are currently two commercial sized barrages in operations. One is located in La Rance, France; the other is in Annapolis Royal, Nova Scotia, Canada.

The image above shows the tidal barrage in La Rance, France.