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Offshore wind power
History and characteristics of an innovative energy source
A true emblem of the energy transition, offshore wind power has already attracted many countries. The production of energy by offshore wind power is indeed very interesting depending on the geographical location of the parks. In France, it particularly has real potential, thanks to a vast and windy maritime landscape.
However, despite the popularity of this innovative source of energy production, many questions remain: how does an offshore park work? How many are there in the world? Which was the first to see the light of day?
Today we answer all these questions.
Offshore wind power, how does it work?
Offshore wind turbines are elements installed off land coasts. They are connected to the electricity network via an underwater cable.
From a technical point of view, they operate in the same way as land wind turbines, except for one detail: their installation at sea allows better use of wind energy, thanks to more powerful blade actuation.
During the first experiments with offshore wind power, and in particular during the launch of the first commercial park in 2002, by the energy supplier Elsam (now Ørsted ), the turbine models used were none other than land wind turbines, simply laid at sea. However, marine conditions led to numerous breakdowns and required a complete repair of the nacelles and blades in 2004. From that point on, manufacturers then reviewed the materials to be used, leading to the current models.
But why put wind turbines at sea?
The advantage of the open sea is that the winds are much stronger and more regular than on land. This then makes it possible to produce up to 60% more energy than on land wind turbines, in particular thanks to the size of the turbines. In fact, an offshore wind turbine is 2 to 3 times more powerful than a land wind turbine.
It is important to know that a wind turbine only starts producing energy when the wind speed is above 10 km/h. For example, a park benefiting from winds of 30 km/h on average is 8 times more productive than a park with winds averaging 15 km/h.
As wind speed increases with altitude, offshore wind turbines are generally very high and have wide blades because the greater the surface area of air stirred, the greater the power of the wind turbine. For example, the turbine models used for the Saint-Brieuc park measure 207 meters high: this is more than Mont Saint-Michel, as shown in the graph opposite.
Finally, the production and installation costs of offshore wind turbines are higher than those of onshore wind turbines, but their efficiency is nevertheless higher.
Offshore wind power in France
Since the launch of the first national call for tenders in 2011, offshore wind power has been booming and has established itself in France as one of the pillars of a society geared towards a so-called “greener” future. The gigantic marine potential of France opens up large energy production capacities. According to Cerema , France benefits from the 2nd largest potential for offshore wind development in Europe.
In addition to having a considerable maritime space, our country also benefits from numerous port areas, and recognized maritime, energy and industrial know-how.
To date, the first offshore wind farm in France is that of Saint-Nazaire (Loire-Atlantique), made up of 80 wind turbines which will produce the equivalent of 50% of the domestic electricity consumption of Loire-Atlantique. It was put into service on September 22, 2022. Those of Saint-Brieuc and Fécamp will follow in 2023.
In a context where it becomes imperative to ensure a form of energy autonomy, the French government tends to adopt certain measures. As such, the Prime Minister, Elisabeth Borne , and the Minister of Energy Transition, Agnès Pannier-Runacher , announced the launch of working groups focused on the theme of energy sobriety. The objective of this project: to reduce our energy consumption by 10% in two years to guarantee our security of supply in the context of the war in Ukraine and, in the longer term, to get France off fossil fuels by 2050.
In a few facts…
Wind power represents the greatest potential for energy development in the marine environment in the coming decade.
France benefits from the 2nd largest offshore wind farm in Europe, after Great Britain.
Europe is the largest offshore wind market in the world.
The first offshore wind farm was built in 1991 in Denmark.
Offshore wind power in Europe and elsewhere
The European Union has acquired undeniable expertise in the field of renewable energies. Indeed, due to its geographical location, it has a vast maritime area, distributed between the Baltic Sea, the North Sea, the Mediterranean, the Black Sea and the Atlantic Sea. As a result, countries like the United Kingdom and Denmark have taken the path of offshore wind power and have independently developed several offshore parks.
On the history side, Denmark was also the host of the very first offshore wind farm, which appeared in 1991, in Vindeby. A true feat for the time, today we could describe it as a miniature park, as the scale and quality of current projects have grown.
By 2050, the European Union aims to achieve its goal of carbon neutrality. To do this, renewable energy production capacity must of course continue to develop. As such, large-scale projects tend to keep this promise. This is the case, for example, of the Seagreen project, the largest offshore wind farm in Scotland which started up on August 22, the date on which the first wind turbine out of 114 was put into service. About 27 kilometers off the coast of Angus County, the park with a total capacity of 1,075 megawatts (MW) (planned to power the equivalent of 1.6 million homes) will be the deepest in the world on a fixed foundation with 59 meters water depth). It is expected to be fully operational in the first half of 2023.
In addition to the numerous parks present in Europe, a few parks exist off the coast of the United States but also Asia, notably in Taiwan where the Formosa 1 saw the light of day in 2019.
The field of possibilities
Nowadays, “low carbon” energies are very topical and are added to the list of solutions to fight global warming. The 100% renewable challenge is launched to reduce health, social and environmental impacts.
Ailes Marines is committed to this formidable challenge by applying the following actions:
- Capturing and taking advantage of the wind off the bay of Saint-Brieuc.
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Focus on research, innovations, developments and environmental analyzes which aim to produce more respectful, responsible and sustainable energies.
- Ensure the protection of our environment and biodiversity.