Saipem introduced in 2019 at OMC its Hexafloat floating wind foundation technology, an innovative and cost-effective pendular floater design aiming at reducing the Levelized cost of Energy (LCOE) for future offshore commercial wind farms.
But offshore floating wind can also be an enabler for oil&gas offshore production decarbonization and long tie-backs development: operators are committing to very ambitious carbon footprint reduction targets, while adapting their production to a low barrel price. These two objectives are often perceived as contradictory because decarbonization is assumed to bring additional production cost. This paper presents Wind2Sub technology, which aims at meeting simultaneously these two objectives.
Wind2Sub principle is to feed subsea systems remote from existing infrastructures or shore with local power supply and auxiliaries provided by one or several floating wind turbines. The floating foundation naturally accommodates the wind turbine generator but also all the utilities that may be needed for a subsea field development and operation, i.e. power distribution, control system, chemicals storage and injection and a back-up energy system able to maintain power supply in the absence of wind.
A conceptual study has been performed for two typical production scenarios: the first one is a low-power case where the floating foundation is powering mostly subsea valves and chemicals injection for the field production and preservation. The second one is a large-power case with a subsea processing and boosting unit and all associated utilities. In both cases the floater design has been adapted to accommodate all equipment and being able to perform maintenance operations in a safe way. Regarding power back-up systems, diesel generators have been considered as base case, combined with diesel storage in the floater. As an alternate, in order to obtain a fully decarbonized solution, power storage systems like batteries and hydrogen have also been considered.
The paper will present the main design characteristics and findings of this conceptual study, as well as preliminary economic evaluations of the Wind2Sub technology.
