Allseas was contracted to install the offshore substation jacket and 2,700-tonne topside at the Yeu-Noirmoutier offshore wind farm using its heavy-lift vessel Pioneering Spirit. Per the DEME Offshore press release on the parallel marine works contract: "Allseas' vessel 'Pioneering Spirit' will be used to install the substation jacket and topside." DEME Offshore separately holds the OSS jacket pre-piling scope and the monopile / transition piece transport-and-installation scope for the 61-turbine array (DEME's own contract; tracked under a separate role). Wind farm capacity, turbine count, the OSS fabrication contractor (Chantiers de l'Atlantique), and the developer-owned grid status under the AO2 / ESSOC carve-out are NOT on the cited DEME page and are tracked separately elsewhere in the project record.