FORCE Technology to design cathodic protection for TetraSub

4C Offshore | Tom Russell
By: Tom Russell 12/01/2023 FORCE Technology

FORCE Technology was selected by Stiesdal Offshore to do the Cathodic Protection (CP) design of the TetraSub floating offshore foundation. The TetraSub is a variant of the Tetra floating foundation concept suited for the 50-200 meter depth range hosting turbines up to 20 MW.

FORCE Technology previously did the CP design of the TetraSpar Demonstrator, another variant of Stiesdal Offshore’s Tetra floating foundation technology brought to full scale test by Stiesdal, Shell, RWE and TEPCO. It was installed at the Marine Energy Test Centre (Metcentre) 10km from shore at a water depth of 200m back in December 2021. FORCE Technology's scope included CP designs of all external surfaces, as well as internal protection of some compartments of the TetraSpar Demonstrator. The CP designs were verified by FORCE Technology's software SeaCorr.

According to FORCE Technology, the modelling enabled Stiesdal Offshore to optimise anode locations to suit fabrication requirements. Also, the protection in the narrow flexible TetraSpar Demonstrator nodes was verified, along with recommendations related to grouting of the TetraSub nodes.
 
In addition to the work related to CP, FORCE Technology has also performed corrosion reviews in the TetraSpar and TetraSub projects and assisted in defining the overall corrosion protection strategy. New design details, coating specifications and castings are some of the items that were reviewed and adjusted during the design phase to ensure ideal corrosion protection.
 
“The project with Stiesdal Offshore is very important for us, as part of our strategy to offer our market leading CP competence, products and services to enter the renewable market. We see a large potential to help our customers in the offshore wind market to obtain their goals to reduce both cost and environmental footprint” said VP Asset Integrity Management, Bjarne Kristoffersen.