System Restoration

Full nominal operation of the Saint-Nazaire offshore wind farm resumed in early February 2024 once the offshore substation transformer fault that had constrained output from early December 2023 was fully rectified. Following the December outage the park had been operating at approximately half its 480 MW nameplate capacity from 21 December 2023, with the remaining repairs delayed by sea-state conditions that prevented sustained technician access to the substation during the winter weeks. Operator EDF Renewables confirmed that all 80 GE Haliade 150-6MW turbines were available and that the offshore substation transformers had returned to nominal duty, restoring the double 225 kV export route to RTE's Prinquiau onshore substation to full carrying capacity. The restart coincided with calmer winter conditions and allowed the park to return to its expected output curve through the spring of 2024. The operator subsequently characterised the cumulative effect of the December 2023 transformer fault on the full 2024 annual production envelope as marginal relative to the underlying wind-resource variability, and no further OSS-attributed outage has been reported since. The full-power resumption also marked the resumption of full grid-balancing services from Saint-Nazaire to the regional Loire-Atlantique network, with the wind farm continuing thereafter as the principal renewable supplier in the département alongside the Prinquiau-linked transmission corridor.