Environmental impact of the Rance Barrage Tidal Power Station.
The barrage has caused progressive silting of the Rance ecosystem. Sand-eels and plaice have disappeared, though sea bass and cuttlefish have returned to the river. By definition, tides still flow in the estuary and the operator, EDF, endeavors to adjust their level to minimize the biological impact.
Situated at the mouth of the Rance Maritime Estuary, with St. Malo (East end) on the RHS and Dinard (west end) on the LHS. The Lock and drawbridge can just be seen on the left (west end) of the barrage.
The Rance barrage looking north to the English Channel
The Rance Barrage, west end, the lock and drawbridge looking upstream (South)
Tidal Energy
Ian G. Bryden, in Encyclopedia of Energy, 2004
The Future of Tidal Power
The high capital costs associated with tidal barrage systems are likely to restrict development of this resource in the near future. What developments do proceed in the early 21st century will most likely be associated with road and rail crossings to maximize the economic benefit. In a future in which energy costs are likely to rise, assuming that low-cost nuclear fusion or other long term alternatives do not make an unexpectedly early arrivals, then tidal barrage schemes could prove to be a major provider of strategic energy in the late 21st century and beyond. Under some local conditions, small-scale barrages might also prove attractive. The technology for tidal barrage systems is already available, and there is no doubt, given the experience at La Rance, that the resource is substantial and available.
It is likely that tidal current systems will appear in experimental form in many places around the world. Initially these will be rated at around 300 kW, such as those planned for the Lynmouth and Yell Sound demonstrations. If these schemes prove successful, then the first truly commercial developments may appear soon. Systems may not presently have the strategic potential of barrage systems but, in the short term at least, they do offer opportunities for supplying energy in rural coastal and island communities. In the longer term, massive sites such as the Pentland Firth, which has been estimated to have the potential to support a 16-GW-capacity development, could become strategically important