OES-Environmental distributes metadata forms (questionnaires) to solicit information from developers involved in environmental monitoring around marine renewable energy project sites around the world. This page provides project descriptions, baseline assessment, post-installation monitoring, and links to available data and reports. Content is updated on an annual basis.

Sabella D10 Tidal Turbine at Ushant Island

Description

The Sabella D10 project was nominated in 2011 as part of the “Marine Renewable Energy Demonstrators” call for interest launched by ADEME (French Agency for Environment and Energy Management) and received funding through the “Investments for the Future” national program.  A complementary subsidy from the European Regional Development Fund was awarded by the Brittany region.

The project is noteworthy in a number of respects:

• widespread social acceptance;
• 100% French construction;
• structural industrial partnerships;
• output dispatched to Ouessant under the control of EDF SEI and ENEDIS; and
• environmental considerations supervised by the Iroise Marine Natural Park.

The project consisted of the construction and 12-month deployment of an industrial tidal stream generator in Fromveur Passage (also known as St Vincent’s Channel). During slack water periods in May 2015, the cable to export the electricity produced was installed between the generator site and the coast of Ouessant (Ushant). In June 2015, the D10 was lowered into the Fromveur Passage in a water depth of 55 m; by November 2015 the D10 was connected to the island network via the previously installed cable. The D10 was the first tidal turbine to supply electricity to the French grid. The generator is 17 m high and has a footprint of 20 x 20 m; its 10-metre rotor can generate 1 MW from the currents in the Fromveur Passage. 

Initial results for the project were promising and in line with expectations, and also opened up future avenues for improvement. In July 2016, at the end of the period for which on-site installation was authorised, the turbine was raised to the surface for technical inspection and expert appraisal. 

The turbine was redeployed in October 2018 as part of the European Intelligent Community Energy (ICE) project. Following continuous electricity production over several months, Sabella’s team focused on testing new control methods at the beginning of 2019 in order to significantly improve the efficiency of the turbine and contribute to the competitiveness of this emerging sector.

Location

Fromveur Passage, off the coast of Ushant Island, Brittany.

Project Progress

In April 2019 Sabella recovered the D10 turbine from the Fromveur Passage for a servicing period of approximately three months off the port of Brest. The turbine is planned to be redeployed on its foundation and connected to Ushant Island, for operation until 2021. 

Papers, Reports, Research Studies

Post-Installation Monitoring: Sabella D10 Tidal Turbine at Ushant Island

Stressor Receptor Study Description Design and Methods Results Status
Collision Fish, Marine Mammals Underwater video monitoring of marine wildlife in 2018 deployment Installation of three underwater cameras orientated to view the turbine blades directly, upwards toward the blades and downwards to the seabed. Pending review of video footage. Underway
Noise Marine Mammals Underwater acoustics study. Based acoustic signature off in situ measurements of the tidal turbine installed by Naval Group off the coast of Paimpol. Noise level measured = 153 dB2 Underway
Birds Monitoring of the Great Crested Cormorant. Video monitoring at the level of tidal turbines, including analysis of videotapes to observe fish behaviour and attendance for a followed by one month in the cold season and one month in the warm season after the installation of the tidal turbines using a camera on concrete stud. The bird most exposed to tidal turbines, due to its abundance and diving abilities, is the crested cormorant, theoretically capable of reaching the rotors. Given the very low risk of collision between tidal turbines and great crested cormorants, no follow-up action was taken specific to this species was not considered necessary. However, Akuo Energy is committed to ensuring that the mammal visualization is also coupled with monitoring of crested cormorants. Underway
Changes in Flow Ecosystem Processes Hydro-sedimentary study. Calculating the drag coefficient characterizing the machines that is the final defining parameter the effect of machines on flow. This was calculated by Sabella using a sizing tool internal. The coefficient is 0.73 and corresponds to the maximum drag obtained for a D14 machine (14 m diameter, but comparable with a D15) with 3 blades and a current velocity of 2.8 m/s, at the torque point maximum. The coefficient used is therefore rather majoring and conservative. Completed
Collision Marine Mammals Detection of mammals with CPODS (ETIP Ocean 2015)
 Two CPODS – one on either side of turbine central mast, with 128 days of measurements on station 1 and 150 days of measurements on station 2. Turbine at rest: from June 2015 there were numerous detections of dolphins, less for porpoises (range of detection of 2-3km for dolphins and 200 m for porpoises)

Turbine functioning: not enough measurements were collected to conclude effects. 		Complete 2015