FAQs
What maintenance do I need to perform on a Hull Vane®?
A Hull Vane® is a fixed, static appendage with zero moving parts. It requires the same maintenance as your vessel’s hull and other appendages, for example its bilge keels.
Fouling (marine growth) is detrimental to its performance, which is why we recommend a good antifouling coating and/or regular cleaning.
Are government subsidies available to reduce the investment costs?
The Hull Vane® helps reduce your vessel’s fuel consumption and emissions levels, which in turn improves its Energy Efficiency Design Index (EEDI).
Every country has its own system of government subsidies, which you’d need to investigate on a case-by-case basis.
However, with or without a government subsidy, a Hull Vane® generally provides such substantial cost savings that it’s advisable to investigate the options in full.
Does a Hull Vane® increase a vessel’s length overall (LOA)?
Generally, a Hull Vane® is attached aft of the stern and does indeed increase its LOA.
To protect the Hull Vane® from tugs and other vessels, we recommend placing a tubular frame above the waterline.
In some cases, a Hull Vane® falls within a vessel’s LOA. Get in touch with us if this might be an issue.
How much does a Hull Vane® cost?
We don’t publish a price list because the cost of designing and building a Hull Vane® depends on too many variables, for example CFD work, production costs and material costs.
To create an optimal design, we have to run a detailed computational fluid dynamics (CFD) analysis for each hull shape. Without a full study, a Hull Vane® might end up increasing your vessel’s resistance instead of reducing its fuel consumption.
A Hull Vane® is an investment that pays itself back over a period of time in the same way as solar panels and real estate do. The risk, however, is extremely low, and the ROI is high – assuming the vessel remains in service and oil prices don’t plummet.
What’s more, there aren’t any hidden future costs because a Hull Vane® has zero moving parts that need replacement.
Incorporating a Hull Vane® in the early design stages can lead to a reduction in the size of the main engines and their exhaust systems. This, in turn, can result in a more compact engine room. The savings you make on installed engine power generally offset most of a Hull Vane’s cost.
Is the Hull Vane® patented?
Yes. The Hull Vane® is protected by patents in all major shipbuilding countries.
It took us over ten years to develop the Hull Vane® and required a significant investment on our part.
How does a Hull Vane® affect my vessel's longitudinal centre of gravity (LCG)?
We usually use steel to fabricate our Hull Vanes, which makes them quite heavy, although this is partially offset by their own buoyancy.
If relevant, we’ll gladly investigate the effect of weight on your vessel’s trim and loading.
And if necessary, we can also fabricate your Hull Vane® using aluminium or lightweight composites.
Are there any disadvantages to attaching a Hull Vane®?
You have to be very careful, when manoeuvring, to avoid any contact with the dock. Also, tugboats won’t be able to push on your vessel’s stern unless you attach a protective structure above the waterline.
In dry dock, there’s more surface area to clean and paint. And you’ll also need to remove as much marine growth as possible, as you do for propellers and rudders.
Can I attach a Hull Vane® to an ice-class vessel?
We’ve performed model testing on a Hull Vane® at the Aker Arctic ice model basin in Helsinki. Speeds in ice are generally too low for a Hull Vane® to provide any significant benefit.
Ice collects around the Hull Vane® when sailing astern, but we didn’t encounter any other major issues.
Can I retrofit a Hull Vane® to an existing vessel?
Yes. A Hull Vane® is equally suitable for new builds and refits.
Although it’s certainly easier to attach a Hull Vane® to a vessel while it’s in dry dock, we’ve successfully fitted out a vessel while it was still in the water.
However, this is only feasible if you’re able to trim the vessel to expose its entire stern above the waterline.
Do I need to modify my vessel’s structure to attach a Hull Vane®?
A Hull Vane® is usually mounted to the vessel’s stern, or occasionally underneath. We adjust the distance between the Hull Vane’s vertical struts to align with your vessel’s bottom girders.
Occasionally, you may need to add internal reinforcement.
Can you estimate the energy savings for my vessel?
A Hull Vane’s performance depends entirely on your specific vessel and its design.
Please get in touch with us if you’d like us to calculate the potential savings for your vessel.
Is CFD reliable enough or should we model-test a Hull Vane® in a towing tank before ordering?
Computational fluid dynamics (CFD) has evolved to such a point in recent years that it’s now more reliable than tank-testing, principally because of the problems associated with scaling viscous effects in tank tests.
Nonetheless, we’ve performed countless tank tests on the Hull Vane® to verify its performance.
What’s more, we’ll gladly perform model testing, on request, to validate our CFD calculations.