Ulstein, a marine enterprise company undertaking both ship design and building services as well as shipping activity, has revealed details of its second hydrogen hybrid wind turbine installation vessel.
According to the company, the J102 zero-emission wind turbine installation vessel (WTIV) will be able to operate for 75% of the time in zero-emission mode. Notably, the company claims that by using readily available technology, the additional cost (over other propulsion systems) is limited to less than 5% of the total CAPEX.
Ulstein notes that most new jack-up designs utilize a battery hybrid system in addition to diesel gensets, with a future option for upgrading to a hydrogen-powered fuel cell system. The downside of a high-power battery energy storage system (BESS) is its heavy weight and cost. That is not ideal for a WTIV design, where weight savings are essential for minimizing elevated weight and optimizing the variable deck load.
Rather than opt for technology to be matured to perfection and make a design that is prepared for future hydrogen-powered fuel cells, Ulstein says it has taken the pragmatic yet realistic approach. “We have carefully analyzed the operational cycle of WTIVs and looked at the power demand in the various modes of operations”, explained Ko Stroo, product manager at Ulstein. “This analysis showed that around 75% of its time, a WTIV is in jacked-up position performing crane operations. Using a combination of a hydrogen fuel cell system and a relatively small battery energy storage system (BESS) is then sufficient to meet the overall power demand on board and crane peak loads.”
“The same design philosophy as on our first hydrogen powered SX190 design resulted in a much more attractive business case when applied to a turbine installation vessel,” added Edwin van Leeuwen, managing director of Ulstein’s Rotterdam design office.
The company says that its hydrogen hybrid system has been developed in such a way that future developments in hydrogen technology can easily be fitted into the vessel without major modifications.
“The limited availability of hydrogen bunker infrastructure in ports is often seen as a major hurdle. With our modular storage layout, we want to break the chicken and egg dilemma,” continued Stroo. “It [the design]creates flexibility to operate the vessel worldwide, even when bunker infrastructure is not yet present.”