| 1️⃣ |
Deck foundation and local steel reinforcement cost
The sail is small on paper, the deck load path is not
|
Wind loads must be carried through foundations, seats, deck plating, and supporting structure in a way that fits the existing vessel arrangement. |
Early vendor cases usually emphasize the propulsion device itself rather than the ship-side structural work needed beneath it. |
Structural analysis, steel detailing, yard planning, and class submissions. |
Capex rises and yard work expands, especially when foundations do not align cleanly with strong structural elements below deck. |
How much steel, access, and rework sits below the advertised equipment package? |
High |
| 2️⃣ |
Stability re-examination and lightweight update cost
A retrofit can reopen a ship-stability workload owners were not expecting
|
Added weight and changed vertical or longitudinal centers can require fresh assessment and sometimes an inclining exercise or related re-evaluation. |
Owners often focus on fuel saving and class approval generally, but not on the practical cost and disruption of stability-related rework. |
Naval architecture, survey preparation, and scheduling while the ship is out of service. |
Project friction rises and the vessel can lose time around survey windows and supporting calculations. |
Does this retrofit change weight distribution enough to reopen a larger stability workload? |
High |
| 3️⃣ |
Electrical and control-system integration cost
The rotor or sail may need more ship-system work than owners assume
|
Wind systems can require switchboard updates, wiring runs, control interfaces, monitoring, and revised load-balance documentation. |
These items sit outside the headline hardware discussion and often emerge as package details later in engineering. |
Electrical drawings, cable routing, commissioning logic, and approval packages. |
More engineering hours, more yard hours, and a wider testing scope than the owner expected. |
What shipboard electrical work is needed for the device to operate safely and reliably in service? |
Core |
| 4️⃣ |
Hydraulic and deployment-system modification cost
Foldable or movable systems can widen the scope fast
|
Some configurations need hydraulic cylinders, deck hydraulic modifications, rail arrangements, or additional control hardware for deployment and stowage. |
Owners may compare technologies based on savings headlines without fully valuing the cost of the chosen deployment method. |
Deck arrangement design, machinery interfaces, and commissioning stages. |
Higher integration capex and more maintenance complexity later in operation. |
Is the chosen deployment concept reducing operating interference enough to justify its added ship-side complexity? |
Money |
| 5️⃣ |
Cargo-operation and deck-workflow interference
Savings can weaken if the rig disrupts how the ship normally works
|
The rig location can conflict with shore cranes, shipboard cargo gear, mooring lines, hatch access, or deck service routines. |
Concept visuals can make placement look simple even when daily deck operations become less efficient after installation. |
Cargo planning, port calls, mooring operations, and turnaround management. |
Commercial savings can be diluted if the system interferes with routine work or slows terminal handling. |
How much operational inconvenience can the ship absorb before theoretical fuel savings start leaking away? |
High |
| 6️⃣ |
Air-draft and route-limitation cost
Some routes and ports may become less comfortable after the retrofit
|
Sail height, stowed profile, and rig arrangement can constrain port access, bridge clearances, or preferred trading flexibility. |
Owners sometimes assess annual savings on wide route assumptions without adjusting for the routes the retrofitted ship may handle less well. |
Voyage planning, charter negotiations, and port acceptance questions. |
The vessel may keep its rating benefit but lose some commercial freedom or route optionality. |
Will this retrofit narrow the ship’s usable trading pattern enough to change the real earnings model? |
Money |
| 7️⃣ |
Performance-verification and savings-validation cost
It is harder to prove savings cleanly than many early cases suggest
|
Owners may need more monitoring, testing, and analysis to demonstrate or internally verify the retrofit’s actual benefit under real conditions. |
Business cases often rely on modeled performance, while real operational verification is less standardized and more demanding. |
Post-installation assessment, charter discussions, and internal capital reviews. |
A retrofit can face internal skepticism or weaker financing confidence if savings are harder to verify than promised. |
How will the owner measure success in service, and what does that measurement system itself cost? |
Core |
| 8️⃣ |
Installation-capacity and slot-risk premium
A growing market can still be constrained in yard and vendor capacity
|
As interest in wind-assisted systems rises, owners can face limited installation slots, specialist attendance bottlenecks, and longer sequencing pressure in retrofit windows. |
Early capex discussions often assume the project can be scheduled when needed, even though vendor and yard capacity may be less flexible. |
Drydock planning, project timing, and total retrofit schedule. |
Cost rises through delay, rushed execution, or compromised timing around other class and repair work. |
What is the cost of getting the hardware approved and installed in the right slot, not just eventually installed? |
High |
