South Brittany Shared Grid Connection for the Offshore Wind Farms

South Brittany Shared Grid Connection for the Offshore Wind Farms

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03

The shared connection includes an offshore electrical substation, three submarine links over 45 km to the landing at Erdeven, and three underground land links over 26 km to the onshore substation at Pluvigner. The offshore substation is described as 70 m square, 30 m above and 90 m below the sea surface. The submarine links are to be buried 0.3–2.5 m deep; on land, the links use trenches 0.5–0.7 m wide and about 1 m deep. The Pluvigner substation occupies 8.4 ha, with four 28 m pylons connecting it to the electricity network.

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03

France.

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03

The opinion's principal environmental issues concern the integrated project, rather than being separately apportioned to each component: seabed forms and habitats, marine and terrestrial biodiversity, migratory fish, birds and bats, marine mammals, landscape and archaeological heritage, and greenhouse-gas effects. It identifies uncertainty in impact assessment, including wetlands whose individual functional effects could not be concluded from the baseline. For the connection, the opinion describes 15 monitoring measures with follow-up over ten years but no specified corrective measures if conservation objectives are not met; only 10 of 48 avoidance, reduction and compensation measures refer to four monitoring measures. The authority recommends better linkage and corrective measures.

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03

Transmission of electricity from both offshore wind farms to the national electricity network through a shared marine and terrestrial connection.

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03

Connection works were expected to start in 2027 and last three years. The opinion gives the installations a 30-year operating life.

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03

The offshore substation is in territorial waters at the boundary of the exclusive economic zone. The submarine connection comes ashore at Erdeven and runs to an onshore substation at Pluvigner; the project requires local-plan changes in six municipalities.

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03

Réseau de transport d’électricité (RTE) is identified as the project owner for the connection and as responsible for the overall project's environmental impact study in the connection authorization application.

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03

The connection environmental authorization is part of a process that precedes the two wind-farm authorization procedures; the overall impact assessment is to be updated as the operations mature. The project requires local-plan compatibility changes in six municipalities and partial downgrading of 14 classified wooded areas. The opinion reports the dossier's residual impact assessment for those local-plan changes as negligible. The environmental authority's opinion is not an authorization decision and is neither favorable nor unfavorable.

Attributed to IGEDD Autorité environnementale opinion: authority synthesis and attributed developer facts.

Source: IGEDD environmental authority native opinion text · publication date not recorded · observed 2026-10-03