Wpd said the three companies would enter its Éliade project in the tender, which will source 250-750MW of offshore capacity in May 2017. The partners have been developing the project since 2016, Wpd said.
"This triad provides an ideal starting point for successfully implementing the project because it unites the experience of offshore specialists Vattenfall, Caisse des Dépôts and Wpd," said Wpd offshore France managing director, Vincent Balès.
"The three players have already implemented a total of 14 offshore wind farms in Europe. In France, they are involved in five projects out of the six, which are in development on the French coast.
"The combination of Vattenfall, Caisse des Dépôts and Wpd has already proved itself in the past. We have successfully implemented various projects like Sandbank or Butendiek together," added Balès.
Vattenfall was to prequalify for the tender in May 2017. Éliade would be Vattenfall's first wind project in France.
All of the candidates for Dunkirk entered a "competitive dialogue" with the state regulator and grid operator to help define the tender terms and off-take agreement, before finalising their bids.
The bids will be judged on three criteria: price, the optimisation of the zone, and consideration for the environment, Vattenfall said. The successful project should be online by 2022.
In December, Vattenfall announced it had entered the Dutch offshore wind tender to develop the Hollandse Kust Zuid site in the North Sea.
The developer has also ordered Siemens Gamesa Renewable Energy's new SG-8.0-167 DD 8MW turbines for in Denmark's Baltic Sea, which it won the rights to develop with a winning bid of €49.90/MWh in November 2016.
Wpd meanwhile had consultations for its 40 turbine Bassure de Baas zone off Boulogne, France, s in August, following reports by regional and maritime authorities.
The German developer is also part of the group behind the 498MW Fecamp and 450MW Courselles-sur-mer projects in France.
Caisse des Dépôts owns a French offshore projects. The two 496MW sites are being developed by Engie and EDPR.
The French investor also has a floating offshore wind project in France, also with Engie and EDPR.