An honest letter on maritime decarbonisation, the limits of alternative fuels, and the work we still have to do at GLOBAtech.
Joshua David — Founder & CEO, GLOBAtech Australia
The maritime industry is in a strange moment. The regulatory floor has moved. Since 2023, four frameworks have landed on top of our sector – the CII grading regime, the 2023 IMO biofouling guidelines (MEPC.378(80)) and the legally binding biofouling framework now being developed behind them, EU ETS extending to maritime, and FuelEU Maritime. The wider IMO Net-Zero Framework, approved in April 2025 and currently awaiting formal adoption after the October 2025 postponement, sits over the top of all of it. Between them, what used to be operating decisions have become compliance obligations. Hull cleanliness, fuel choice, voyage planning, port selection — all of it is now priced, graded, audited, or moving in that direction. The industry has been told what to do. The conversation about how is still wide open.
In the public press, “how” mostly means future fuels. Methanol orderbooks. Ammonia bunkering pilots. Hydrogen retrofits. LNG as a transition. Wind-assist. e-fuels at scale. All of it is real. All of it is necessary. None of it is the answer for the fleet that is already in the water.
That is not a controversial view inside the industry – but it is sometimes a controversial one outside it, so let me say it plainly: the existing global fleet, the one trading cargo right now, will not be substantially powered by alternative fuels for at least another decade, and most of it not in its current operating lifetime. The bunkering infrastructure does not exist. The production volumes do not exist. The price parity does not exist. The orderbook for genuinely zero-carbon-capable newbuilds is a single-digit percentage of the existing fleet. The fuel transition will happen. It will not happen fast enough to meet the compliance regime that has already arrived.
So what does happen in the meantime? In the meantime, every fleet operator I speak to is being held to compliance metrics that bite right now – CII grading, EU ETS allowances, biofouling reporting – and the only large lever they can pull at fleet scale, today, on the assets they already own, is hydrodynamic efficiency.
That is what this letter is about.
The single biggest needle move
Hydrodynamic efficiency, in practical terms, is hull cleanliness, propeller cleanliness, running gear cleanliness; the underwater geometry of a ship not being disrupted by biological growth. ISO 19030 is the measurement standard. The literature is settled: a meaningfully fouled hull adds somewhere between 10% and 30% to fuel burn at constant speed, depending on hull form, voyage profile, and the severity of fouling. The variability is wide; the direction is not. Fouling costs fuel. Fuel costs carbon. Carbon now costs money.
I want to put that more strongly. Of every intervention available to an existing vessel in 2026 — slow steaming, weather routing, wind-assist retrofits, waste-heat recovery, advanced coatings, in-water hull cleaning, voyage optimisation, propeller polishing – hull cleanliness is the largest single ROI lever, and the only one that compounds across every other intervention. A clean hull makes slow steaming work harder. A clean hull makes route optimisation pay more. A clean hull makes a wind kite worth installing. Nothing else has that property.
It is also, candidly, the lever the industry has the worst tools for. Hull cleaning by ROV or diver, on a reactive schedule, in port windows that don’t always exist, with growing port-state restrictions on in-water cleaning, with biofouling biosecurity protocols tightening across major maritime jurisdictions, with dry-dock intervals being stretched for cost reasons – the operational reality of keeping a deep-sea hull clean is harder than the marketing decks suggest. Modern coatings help, sometimes a lot. They do not solve.
This is the problem GLOBAtech has been working on, in one form or another, for almost two decades.
Where we sit, and what the record covers
ENVSonic is the commercial output of 20 years of operating in this category. Three platform generations. More than a thousand vessels and industrial assets protected. 14+ countries of deployment. Two patents pending. Vertically integrated; every layer from PCB design and embedded firmware through to AI-monitored fleet dashboards designed and operated under one roof in Australia.
I want to be precise about what that record covers, and where the frontier still is — because the conversation in this category is too often had at the brochure level, and the people buying multi-million-dollar decarbonisation outcomes deserve better than that.
Ultrasonic antifouling is a mature, deployable technology in the categories where the physics works cleanly. Raw-water systems, sea chests, box coolers, heat exchangers, internal seawater piping, stationary industrial cooling, processing barges, aquaculture infrastructure – we and several capable competitors have a strong industry-wide track record there. The acoustic dose, the coupling geometry, the operational profile, the failure modes – all well understood. ENVSonic platforms run on offshore rigs, on processing barges, on cooling infrastructure, on stationary maritime assets, every day. It works.
On working vessels – SOVs, MPVs, tugs, fast workboats, ferries, super yachts, naval and coast guard hulls – the platform also has a strong, multi-decade record. Steel hulls, supportive geometry for transducer placement, predictable duty cycles, dose-to-coverage ratios well inside what the technology can deliver. The category as a whole, and I will include capable competitors here alongside ENVSonic, has genuinely serious products in this segment. Some of it is very good. Some of it is not. A buyer who does their homework can find real technology.
The deep-sea commercial hull is where the honest conversation has to happen.
The unsolved part
Bulkers, tankers, container ships, large RO-ROs, LNG carriers – the deep-sea commercial fleet – represent the vast majority of the maritime industry’s fuel consumption and the vast majority of its carbon liability. They are also where ultrasonic antifouling, as a category, has the most work still to do. I will not dress that up.
We have tested. Our partners have tested. The competitive landscape has tested. What ultrasonic antifouling does extremely well on a 30+ metre tug, it does not yet do extremely well across the full wetted surface of a 300-metre VLCC. The hull plate geometry, the internal structural members that absorb and re-radiate acoustic energy in complex ways, the operational profile of months at sea between hull inspections, the ballast vs laden characteristic, the in ballast environment for transducers, the half a metre of silt in the tanks from years of operation, the propeller and rudder system that sits outside the natural reach of conventional transducer placement where the physics just don’t work – these are real engineering constraints, and they are the constraints the next generation of the platform has to clear.
That is the honest position. It is also why I am writing this letter.
What we have learned, in the years of testing, is which parts of the deep-sea hull system the current platform addresses well, and which parts it does not. Sea chests, box coolers, internal cooling loops, engine-room raw-water systems are all addressed today, with strong empirical evidence. Propeller and adjacent running gear – partially addressed, with specific GLOBAtech products under active development against this exact problem, including patent-pending technology aimed at the propeller and shaft area where fouling has a disproportionate hydrodynamic impact relative to its surface area. Full external hull plate coverage at deep-sea commercial scale, the frontier. The work in progress. The unsolved part that GLOBAtech is actively engineering.
I am not going to publish the technical specifics of what we have learned, because that work is patent-pending. What I will say is this: we know where the coverage falls off, we know why it falls off, we know what the architectural answer looks like, and we are building it. That is the entire purpose of two decades of compound engineering investment – to be standing at the frontier of the problem with the empirical record, the patents, the manufacturing base, and the customer relationships needed to close the gap. We are the company shape that can do this work. I do not say that lightly.
On competitors, and what buyers should ask
There are good companies in this category. There are also companies selling products that, charitably, do not do what their datasheets claim. Buyers in the deep-sea fleet segment should ask hard questions, demand empirical evidence, and not take any single supplier’s word for it — including ours. The technology is too important, the carbon consequences too real, and the compliance stakes too high to be sold on marketing. And in a relatively young category, where the failure of one brand carries decade-long consequences for the rest, success is the only metric worth relying on. Ultrasonic antifouling can and will solve this problem – but it will not get there through sales and marketing. It will get there through hard, ISO 19030-measured results, because after four years into a docking cycle, hopes and dreams will not keep a hull clean.
The bar is straightforward: ISO 19030-aligned measurement, real installations, real performance data, transducer engineering you can interrogate, manufacturing you can audit, and independent verification wherever it is available. That is the standard the industry should be holding suppliers to, and that is the standard we are committing to ourselves.
What I would not do, as a buyer, is conclude that because no ultrasonic platform has yet fully solved the deep-sea commercial hull at scale, ultrasonic antifouling is not the answer. The answer is being engineered right now. It is being engineered by a small handful of serious companies. I believe, with the conviction that comes from nearly two decades inside the engineering problem and operating the business of it, that GLOBAtech is going to be one of the companies that gets there. And “there” is sooner than you might think. I believe we are going to be the one that gets there with the empirical record and the manufacturing depth to deploy at multi-fleet scale.
Plan A, and the Plan B that isn’t one
I get asked, when I speak to investors and partners, what GLOBAtech’s Plan B is. Jeff Bezos has answered that question better than I can: “I don’t like a Plan B. Plan B should be to make Plan A work.” That is exactly the position we are in. We are not going to diversify away from the deep-sea hull problem. We are not going to pivot the company into adjacent categories that distract from the core mission. The opposite. We are going to compound effort, capital, and attention against the part of the problem that is not yet solved, until it is solved. Twenty years of company effort goes into the current stages of engineering. That is the plan.
The aim – and I am stating it publicly here so that we can be held to it – is for ENVSonic to become the most important compliance and efficiency technology under the new IMO regulatory regime. The platform that helps fleet operators stay in CII band. Manage EU ETS exposure. Satisfy biofouling guidance. Extend dry-dock cycles. Reduce reactive hull-cleaning intervals. And – the metric that ultimately matters more than any of those – burn less fuel per nautical mile of cargo moved.
Every tonne of fuel saved is carbon not emitted, today, on the assets already in the water. The fuel-transition story is real. So is this one. The two are not in competition with each other; they are sequenced. Hydrodynamic efficiency now. Alternative fuels as they become commercially and operationally available across the global bunkering network. The vessel that runs cleaner today is also the vessel that arrives at the fuel transition cheaper to operate when it gets there.
A public commitment
I want this letter read as a public commitment, not a marketing document.
GLOBAtech intends to play its part in the decarbonisation of the maritime industry as the technology house that delivers the hydrodynamic efficiency answer for the existing global fleet. We will keep the empirical evidence transparent where commercial agreements allow. We will keep the supplier-level honesty I have tried to demonstrate in this letter. We will name what we have solved, what we have partly solved, and what we have not yet solved. And we will keep building – generation after generation, transducer after transducer, fleet pilot after fleet pilot – until the unsolved part of the deep-sea commercial hull fouling prevention is solved.
The platform that the next decade of maritime decarbonisation requires is not yet finished. The company shape that is going to finish it has been quietly compounding since 2006. After 17 years of technical development and 20 years in business, we feel we have the formula. The next ten years are about delivering it.
And when we do, when ENVSonic is deployed at multi-fleet scale, when the deep-sea commercial hull problem is closed, when the existing global fleet is moving cargo at a meaningfully lower carbon cost per nautical mile – it will likely stand as the single most impactful needle move maritime decarbonisation deep tech has produced.
That is the prize we are engineering toward. That is where we are. That is what we are doing. That is what GLOBAtech is for.
— Joshua David Founder & CEO, GLOBAtech Australia Coomera, Queensland · May 2026