Engineering-related scientific and technical services

Description

TenneT is obliged to connect offshore wind farms in the southern North Sea to the onshore power grid. The TenneT TSO Grid Field Operation - Offshore (GFO-O) as its organisational unit manages the operations of the German and Dutch high voltage cable connections from land to the offshore wind farms, so-called grid connection systems (GCS). The offshore wind farms (OWF) are constructed and operated by third parties. After construction the GCS are handed over to TenneT GFO-O and transferred to the operational phase. Adequate maintenance to the fixed steel offshore structures must be ensured in this phase. The Underwater inspections of the Fixed Steel Structures form an integral part of the maintenance and the source of information on which maintenance is scheduled. Besides these scheduled surveys that are part of the maintenance plans, the surveys are also needed in case of unexpected damages or incidents. This scope of work is intended to describe measures which need to be undertaken to survey the underwater fixed steel structures as part of their regular maintenance plan or due unexpected circumstances.