SDiscounting has led to a comforting, but mistaken, belief: that key efficiency ratios on paper tell the owner what clean technology will deliver in the real world. In fact, a single figure quoted out of context, or the fuel savings recorded on a single voyage and scaled across the fleet, says almost nothing about whether the system in front of the owner will operate reliably on his vessel, in his commercial operations, over the operational life of the asset.
Most of the performance figures currently used by the industry when procuring clean technologies are recorded under controlled conditions, on a single chassis, and during appropriate operating windows. In air lubrication, standard reference points are often taken from sea trials carried out in light or ballast conditions, where compressors have less hydrostatic pressure to work against and the system can be served at its best. In other words, what these results say about a different ship, at a different tonnage level and in a different trade, is much less than the headline savings figure might suggest.
Independent results now prove it. A summary of ideas published this year by the Maersk McKinney-Muller Zero Carbon Shipping Center – drawn from owners and charterers operating active compressor-based systems – reported real-world net savings of zero to six percent, varying with hull shape, draft, speed and sea state. This is a significant deviation from the numbers that routinely appear on the market, and a reminder that one key number tells the owner very little about how the system on his vessel is behaving.
The result is a procurement environment in which owners cannot confidently choose between the systems offered to them. Some have stopped buying altogether, waiting for the evidence base to mature. This is bad for the path to decarbonisation in the shipping sector, and it is bad for trusted suppliers who have invested in real engineering and now find themselves competing in a market that only reads headline numbers. It is essentially a credibility gap – and it widens every time the regime fails to deliver on the broad promise it made on paper.
That’s why shipowners must change the question they ask. Instead of “What did this system achieve in someone else’s test conditions?”, they should ask “What do you expect it to do on my ship, in my trades, at the air currents and speeds I’m actually operating at?” Vessel-specific manuals should be the primary expectation before any capital expenditure is committed, and no system should be purchased that cannot be designed to this level of specificity.
This is even more important now that the way ships are operated has changed at the feet of their owners. Tighter carbon intensity regulations and fluctuating fuel costs are pushing ships into slower, more volatile steaming, and ships are now spending significant time below the design speeds at which headline numbers are typically recorded. Technology that operates in a narrow speed range is a very different proposition from technology designed to deliver the full range of speeds and conditions in which a vessel is actually operated.
Most compressor-based hollow air lubrication systems are built around a narrow production window; They are designed not to fall outside their useful operating range, with their compressors operating only to keep the cavities filled rather than to achieve net savings. Thus a ship with high-speed legs and slow ballast returns spends much of its time in conditions where first-generation systems offer little or no upside. Coincidentally, these trading patterns are exactly the conditions toward which regulatory compliance steers the global fleet. Armada designed its Passive Air Lubrication System (PALS) to answer that: it uses the forward motion of the ship to draw in and distribute air, without a compressor, so it continues to deliver net positive performance across exactly those slower, more variable shapes.
However, building an improved system is only half the argument. Producing reliable evidence for a given vessel is essentially an accuracy problem: how will the system behave on a hull to which it has not yet been installed, upon integration proposed by the owner, within its real operating envelope? This question cannot be answered by replicating what technology has done elsewhere. A large installed base does not equate to depth of understanding and, essentially, the high volume of orders on a single ship type is simply repetitive data on a non-representative sample of individual ships.
Answering this challenge requires a robust experiment and modeling program built on the variables that govern performance: large-scale cavitation tunnel testing on individual compartments, model-scale towing tank operation across multiple hull shapes, extensive trial installations, and multi-stage CFD analysis, independently confirmed by industry-leading partners.
This basis is what allows the supplier to contractually support its expectations – and ultimately what enables it to provide performance guarantees, with the commercial consequences of non-delivery in the conversation. In a market where claims routinely exceed what can be verified on board to the owner, this willingness is the clearest indication that the supplier’s model can be trusted.
Decarbonizing shipping depends on owners being able to believe in what they are selling. This starts with shipowners demanding the right evidence – and they remain unwilling to commit a single pound of capital expenditure without it.
Source: Written by Alex Routledge, CEO of Armada Technologies
