The Thortonbank project was the first offshore wind project to be developed in the Belgian North Sea. In order to prove the viability of this innovative concept and the policy tool put in place, the Belgian authorities required C-Power to start the project with a pilot phase (also named demonstration phase). This pilot phase is the 1st of the 3 phases of the C-Power project.

Phase 1 consists of six 5M Senvion turbines in a single line. The wind turbines are built on gravity-based foundations and are connected together by 33 kV cables. They are then linked to the onshore high voltage station through a 150 kV export cable, which is currently used at 33 kV with an onshore transformer to inject into the 36 kV grid.

project phase 1

Construction was started on May 23th, 2007 and after building the wind turbines in 2008, connecting them to the electricity grid was done at the end of 2008. Since the beginning of 2009 electricity has already been injected into the transport network. On May 10th, 2009, the last wind turbine was started up after the perfect running of all test procedures.

Supply and works execution

The turbines were provided by Senvion who is responsible for the supply, Operation and Maintenance of the wind turbines during the first 10 years of exploitation.
The installation of the turbines was executed by the THV Seawind consortium, which was also in charge of the balance of plant (onshore works, construction and installation of the foundations and installation of the cables).
The offshore as well as the onshore cables are designed and supplied by ABB.
For Phase II and III of the project, the same contractors have been selected.


The initial investment for this pilot phase amounts to 153 million euro.
This amount includes the budget of the three main construction contracts; meaning wind turbine supply (Senvion), electrical infrastructure supply (ABB) and all maritime and electrical construction works (THV Seawind); and all financing costs and fees.

It was financed on a non-recourse basis in May 2007:

  • EUR 90,286,340 Term Loan (Senior Facility)
  • EUR 11,200,000 Contingent Facility (Senior Facility)
  • EUR 20,000,000 Mezzanine facility

Senior facilities were provided by Dexia Bank Belgium, Dexia Crédit Local, Société Générale, Rabobank and KBC while Mezzanine was provided by Rabobank only.


A"Construction All Risks" Insurance including ALOP (Advanced Loss of Profit) was contracted with Ethias.
Operational insurance was provided by Delta Lloyd.