“According to the first measurements, Dunkirk will be the most profitable wind power site.” Jérémy Tolu, project manager at Nass&Wind, is convinced. The work carried out since May by the Brittany-based company, who installed a buoy off Dunkirk to take wind measurements (our issue of 7 June), adds grist to the mill of those promoting the idea of offshore wind power on the shoals of Dunkirk. It confirms the decision of Environment Minister Ségolène Royal to allocate the site for the installation of offshore wind turbines in the framework of the third national call for bids. And above all, it may be an argument for attracting investors to support the creation of the future farm.
“One of the most promising sites around the French coasts”
The open sea off Dunkirk is described as “one of the most promising sites around the French coasts” by Nass&Wind, who have already worked in areas such as Saint-Nazaire and Saint-Brieuc. “The Dunkirk site offers faster wind speeds,” commented Jérémy Tolu. “Given its speed, and the intensity which turns the turbines faster, it will generate more power.” This is the reason for its greater profitability, because “wind is the most important factor for calculating the profitability of a wind farm project accurately, and hence the cost of electricity,” the specialist continued.
The measurements of Nass&Wind are particularly useful in that they were taken between May and September, a fairly calm period in terms of wind. The also provide reliable data because of the technique used: “A box installed on our buoy sends a vertical laser signal which can measure up to a height of 200 m. The important thing is to know the characteristics of the wind at the height of the turbine’s hub, i.e. 100 metres. Over the four months of measurements, our system was in operation for 99% of the time. And it yields actual measurements, not models or extrapolations,” explained Jérémy Tolu.
These results must be supplemented: “For a wind farm project, you need at least one year’s measurements to gauge the seasonal variations and gain a good assessment of the wind, in terms of both speed and direction,” added the project manager.
An alternative area
Once Dunkirk had been chosen as the site to host an offshore wind farm, the government authorities defined an area for its installation. While generally favourable to offshore wind power in the region, maritime operators were nonetheless critical of the positioning of this zone (our issues of 12 and 15 July): it was too close to the shore, encroaching on the accessways to the port. They also questioned the distance of 5 miles from the traffic separation scheme (TSS) imposed by the Prefecture Maritime.
In response, the Maritime and Commercial Union (1) came up with an alternative solution, which it put forward during this summer’s public consultation. It proposes a smaller area than the 180 km2 delineated by the Prefecture Maritime: “Approximately 70 km2 usable. This potential area within the 180 km2 area could be situated inside a space delineated by the Route des Flandres (2) and the Belgian border, and at a safe distance from the southern edge of the traffic separation lane.” The MCU are also calling for publication of the study which defined the 5-mile zone.
“We hope our comments will be considered and that the project will develop in the right direction,” said Jean-Charles Le Gall, President of the MCU, who is convinced of the ecological and economic advantages of offshore wind power for Dunkirk. “The ground work for the project has been done. As I see it, we are getting results which should satisfy most maritime operators,” considered Admiral Ausseur, Maritime Prefect for the Channel and the North Sea.
1) An association of operators connected with the port, currently comprising 64 firms representing some 1,750 employees.
(2) A road leading to the port, west of Dunkirk.