Rance Tidal Power Station - History

History

An early attempt to build a tidal power plant was made at Aber Wrac'h in the Finistère in 1925, but due to insufficient finance, it was abandoned in 1930. Plans for this plant served as the draft for follow-on work. Use of tidal energy is not an entirely new concept, since tidal mills have long existed in areas exposed to tides, particularly along the Rance.

The idea of constructing a tidal power plant on the Rance dates to Gerard Boisnoer in 1921. The site was attractive because of the wide average-range between low and high tide levels, 8 m (26 ft) with a maximum perigean spring tide range of 13.5 m (44.3 ft). The first studies which envisaged a tidal plant on the Rance were done by the Society for the Study of Utilization of the Tides in 1943. Nevertheless, work did not actually commence until 1961. Albert Caquot, the visionary engineer, was instrumental in the construction of the dam, designing an enclosure in order to protect the construction site from the ocean tides and the strong streams. Construction necessitated draining the area where the plant was to be built, which required construction of two dams; an effort which took two years. Construction of the plant commenced on the 20th of July 1963, while the Rance was entirely blocked by the two dams.

Construction took three years and was completed in 1966. Charles de Gaulle, then President of France, inaugurated the plant on the 26th of November of the same year. Inauguration of the route crossing the plant took place on 1 July 1967, and connection of the plant to the French National Power Grid was carried out on the 4th of December 1967. In total, the plant cost ₣620 million (approximately €94.5 million). It took almost 20 years for the La Rance to pay for itself.