The Rance Tidal Power Station is a

tidal power Tidal power or tidal energy is harnessed by converting energy from tides into useful forms of power, mainly electricity using various methods. Although not yet widely used, tidal energy has the potential for future electricity generation. Ti ...

station located on the

estuary An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...

of the

Rance River The Rance (; br, Renk) is a river of northwestern France. It is long. It flows into the English Channel between Dinard and Saint-Malo. Before reaching the Channel, its waters are barred by a 750 metre long dam forming the Rance tidal power plan ...

Brittany Brittany (; french: link=no, Bretagne ; br, Breizh, or ; Gallo language, Gallo: ''Bertaèyn'' ) is a peninsula, Historical region, historical country and cultural area in the west of modern France, covering the western part of what was known ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

. Opened in 1966 as the world's first tidal power station, it is currently operated by

Électricité de France Électricité de France S.A. (literally ''Electricity of France''), commonly known as EDF, is a French multinational electric utility company, largely owned by the French state. Headquartered in Paris, with €71.2 billion in revenues in 2 ...

and was for 45 years the largest tidal power station in the world by installed capacity until the

South Korea South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed ...

Sihwa Lake Tidal Power Station Sihwa Lake Tidal Power Station is the world's largest tidal power installation, with a total power output capacity of 254 MW. When completed in 2011, it surpassed the 240 MW Rance Tidal Power Station which was the world's largest for 45 years. It ...

surpassed it in 2011. Its 24

turbines A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful Work (physics), work. The work produced by a turbine can be used ...

reach peak output at 240

megawatt The watt (symbol: W) is the unit of Power (physics), power or radiant flux in the International System of Units, International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantification (science), ...

s (MW) and average 57 MW, a

capacity factor The net capacity factor is the unitless ratio of actual electrical energy output over a given period of time to the theoretical maximum electrical energy output over that period. The theoretical maximum energy output of a given installation is de ...

of approximately 24%. At an annual output of approximately 500 GWh (491 GWh in 2009, 523 GWh in 2010), it supplies 0.12% of the power demand of France. The power density is of the order of 2.6 W/m². The cost of electricity production is estimated at /kWh. The barrage is long, from Brebis point in the west to Briantais point in the east. The power plant portion of the dam is long and the tidal basin measures .

History

An early attempt to build a tidal power plant was made at

Aber Wrac'h The Aber Wrac'h is a small village and port located on the river Wrac'h in the commune of Landéda in the department of Finistère in France, located in Brittany. The Wrac'h's source is in Trémaouézan. It travels through Ploudaniel, Le Folg ...

in the

Finistère Finistère (, ; br, Penn-ar-Bed ) is a department of France in the extreme west of Brittany. In 2019, it had a population of 915,090.

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

tide Tides are the rise and fall of sea levels caused by the combined effects of the gravity, gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide t ...

s, particularly along the

Rance Rance may refer to: Places * Rance (river), northwestern France * Rancé, a commune in eastern France, near Lyon * Ranče, a small settlement in Slovenia * Rance, Wallonia, part of the municipality of Sivry-Rance ** Rouge de Rance, a Devonian re ...

. 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, with a maximum

perigean spring tide A perigean spring tide is a tide that occurs three or four times per year when a perigee (the point nearest Earth reached by the Moon during its 27.3-day elliptic orbit) coincides with a spring tide (when the Sun, the Moon, and Earth are nearly ...

range of . 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 Albert Irénée Caquot (1 July 1881 – 28 November 1976) was considered the "best living French engineer" for half of a century. He received the “ Croix de Guerre 1914–1918 (France)” (military honor) and was Grand-croix of the Légion d ...

, 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 which took two years. Construction of the plant commenced on 20 July 1963, while the Rance was entirely blocked by the two dams. Construction took three years and was completed in 1966.

Charles de Gaulle Charles André Joseph Marie de Gaulle (; ; (commonly abbreviated as CDG) 22 November 18909 November 1970) was a French army officer and statesman who led Free France against Nazi Germany in World War II and chaired the Provisional Government ...

, then

President of France The president of France, officially the president of the French Republic (french: Président de la République française), is the executive head of state of France, and the commander-in-chief of the French Armed Forces. As the presidency i ...

, inaugurated the plant on 26 November of the same year. Inauguration of the road crossing the plant took place on 1 July 1967, and connection of the plant to the French National Power Grid was carried out on 4 December 1967. In total, the plant cost ₣620 million (approximately

€ The euro sign () is the currency sign used for the euro, the official currency of the eurozone and unilaterally adopted by Kosovo and Montenegro. The design was presented to the public by the European Commission on 12 December 1996. It consists o ...

94.5 million). It took almost 20 years for the La Rance to pay for itself.

Assessments

In spite of the high development cost of the project, the costs have now been recovered, and electricity production costs are lower than that of

nuclear power Nuclear power is the use of nuclear reactions to produce electricity. Nuclear power can be obtained from nuclear fission, nuclear decay and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced b ...

generation (1.8 ¢/kWh versus 2.5 ¢/kWh for nuclear). However, the

of the plant is 28%, lower than 85–90% for nuclear power.

Environmental impact

The barrage has caused progressive silting of the Rance ecosystem.

Sand-eel Sand eel or sandeel is the common name used for a considerable number of species of fish. While they are not true eels, they are eel-like in their appearance and can grow up to in length. Many species are found off the western coasts of Europe ...

s and

plaice Plaice is a common name for a group of flatfish that comprises four species: the European, American, Alaskan and scale-eye plaice. Commercially, the most important plaice is the European. The principal commercial flatfish in Europe, it is also ...

have disappeared, though

sea bass Sea bass is a common name for a variety of different species of marine fish. Many fish species of various families have been called sea bass. In Ireland and the United Kingdom, the fish sold and consumed as sea bass is exclusively the European ba ...

and

cuttlefish Cuttlefish or cuttles are marine molluscs of the order Sepiida. They belong to the class Cephalopoda which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal shell, the cuttlebone, which is used for control of ...

have returned to the river. By definition, tides still flow in the estuary and the operator,

EDF EDF may refer to: Organisations * Eclaireurs de France, a French Scouting association * Education for Development Foundation, a Thai charity * Électricité de France, a French energy company ** EDF Energy, their British subsidiary ** EDF Luminus, ...

, endeavours to adjust their level to minimize the biological impact.

Tourist attraction

The facility attracted approximately 40,000 visitors in 2011. A lock for navigation at the west end of the dam allows the passage of 1,600-tonne vessels between the

English Channel The English Channel, "The Sleeve"; nrf, la Maunche, "The Sleeve" (Cotentinais) or ( Jèrriais), (Guernésiais), "The Channel"; br, Mor Breizh, "Sea of Brittany"; cy, Môr Udd, "Lord's Sea"; kw, Mor Bretannek, "British Sea"; nl, Het Kana ...

and the

. Departmental road 168 crosses the dam and allows vehicles to travel between

Dinard Dinard (; br, Dinarzh, ; Gallo language, Gallo: ''Dinard'') is a Communes of France, commune in the Ille-et-Vilaine Departments of France, department, Brittany (administrative region), Brittany, northwestern France. Dinard is on the Côte d'� ...

and

Saint-Malo Saint-Malo (, , ; Gallo: ; ) is a historic French port in Ille-et-Vilaine, Brittany, on the English Channel coast. The walled city had a long history of piracy, earning much wealth from local extortion and overseas adventures. In 1944, the Alli ...

. There is a

drawbridge A drawbridge or draw-bridge is a type of moveable bridge typically at the entrance to a castle or tower surrounded by a moat. In some forms of English, including American English, the word ''drawbridge'' commonly refers to all types of moveable ...

where the road crosses the lock which is raised to allow larger vessels to pass. The Rance estuary is the first part of the inland waterway from the English Channel to the Bay of Biscay via the Canal d'Ille-et-Rance and the river Vilaine.

References

External links

{{Commons category, Rance Tidal Power Station
University of Strathclyde Rance Project (case study)

Energy infrastructure completed in 1963 Tidal power stations in France Coastal construction Buildings and structures in Ille-et-Vilaine Saint-Malo Tidal barrages Électricité de France Tourist attractions in Ille-et-Vilaine Articles containing video clips 1963 establishments in France