Deme completes foundation installation at France’s first commercial offshore wind farm

Belgian marine contractor Deme Offshore and French construction firm Eiffage Métal have completed installation of the 80 XL monopile foundations at the 480MW Saint-Nazaire (Parc du Banc de Guérande) Saint-Nazaire (Parc du Banc de Guérande) (480MW) Offshoreoff Le Croisic, Pays de la Loire, France, Europe Click to see full details project – which is due to be France’s first commercial offshore wind farm.

They had started installing the foundations at EDF Renewables, Enbridge and CPP Investments’ project in spring 2021 and continued working through the winter.

Bart De Poorter, general manager at Deme Offshore said the contractors were able to overcome challenges with installing the foundations in solid rock and working in harsh conditions due to two technological innovations.

They used a 50-tonne offshore foundation drill – jointly designed by Deme Offshore and tunnel boring machine manufacturer Herrenknecht – to install the monopiles in solid rock.

The contractors also used a monopile drilling, installation and grouting system, Modiga, to encapsulate the drilling and installation operations, shielding them from the harsh Atlantic marine environment. This enabled operations to be carried out without being disrupted by the weather or Atlantic conditions, and so installation could be completed faster, a Deme spokesperson explained.

Bart De Poorter, general manager at Deme Offshore, said: “Deploying this world’s first equipment enabled us to complete the installation well ahead of schedule. 

“Installation operations continued through the winter season, despite the combination of severe weather conditions and the harsh Atlantic ocean environment.”

In addition to the foundations now being in place, turbine installation is also under way. GE Renewable Energy had installed the first of 80 of its Haliade 150-6MW turbines at the project in April.

Project commissioning is expected by the end of the year.

Saint-Nazaire was one of three EDF offshore wind projects to be awarded a decade ago in an auction for nearly 2GW of offshore wind capacity. 

However, the sector had become embroiled in a long saga of “permitting hurdles, red tape and legal challenges”, as described by industry association WindEurope, before gaining final approval in 2019. 

While Saint-Nazaire is France’s first commercial offshore wind farm to approach completion, one Vestas V80-2.0 turbine has been operational at Ideol’s 2MW Floatgen Floatgen (2MW) Offshoreoff Le Croisic, France, Europe Click to see full details floating offshore wind pilot since 2018. 

A number of other offshore wind projects are in the development phase, accounting for nearly 9GW of capacity, according to Windpower Intelligence, the research and data division of Windpower Monthly.

Earlier this year, President Emmanuel Macron outlined plans for France to create 40GW of offshore capacity from 50 wind farms by 2050.