Broadly speaking, ships of the future will evolve naturally in line with economic trends, legal constraints, and advancing technological possibilities. And the over-arching trends of green shipping, in particular decarbonising shipping, and digital transformation with all its facets are the leitmotifs.
On 11 May 2023, Volker Bertram, Senior Project Manager at DNV (email@example.com), acted as keynote speaker at the Royal Dutch Society of Marine Engineers’ (KNVTS) symposium “KNVTS takes soundings” to celebrate the organisation’s 125th anniversary. SWZ|Maritime’s July-August 2023 issue looks back on the presentations held there. Bertram’s keynote was included in this special and is now also published here.
The long-term economic and ecological pressure for energy efficiency will inevitably lead to lower ship speeds. As a result, bulbous bows are likely to shrink or even disappear, ships will become wider and shorter, and propulsion improving devices (PIDs) may become standard. Ship hulls will continue to be made of steel. Composites will be limited mainly to weight-sensitive niche applications, such as high-speed craft, navy vessels, or cruise vessel superstructures.
The broader trend towards cleaner fuels will lead to a mix of various fuel options on the market. Liquefied natural gas (LNG) is likely to play a major role for the next two decades, but will then fade out as a fossil fuel with a still significant carbon footprint. Biofuels come with minimum changes to machinery and crew training. Longterm, maritime biofuels may be based on algae and offshore production akin to fish farming.
Methanol also comes with few changes for machinery and crew, but production and bunkering infrastructure worldwide for clean methanol needs to be ramped up. Ammonia is a convenient way to store hydrogen. Large-scale production facilities exist worldwide for ammonia as cargo (fertilizer), but facilities for clean and cost-effective production have yet to evolve.
Hydrogen (as liquid LH2) is less likely to gain significant market shares in blue shipping due to the difficulties and costs in storage and transport. Nuclear fuels are unlikely to gain significant market shares, due to technical and political hurdles. More likely, nuclear power will be used on land to produce synthetic fuels such as methanol and ammonia.
Most “blue shipping” cargo ships will continue to rely on diesel engine technology. Cleaner fuels will make some of the periphery of traditional main engines obsolete. Overall, cleaner fuel and the more robust set-up of the engine room together with smarter condition-based maintenance schemes will reduce the workload of the engine department. In addition, we will see the rise of e-power on ships, mostly in the form of fuel cells and batteries, mostly on short sea shipping.
Antifouling, air lubrication and WASP
Antifouling strategies will shift from biocidal antifouling coatings to more sustainable technologies, including easy-to-clean coatings and frequent robotic cleaning (grooming) for large surfaces and ultra-sonic protection for niche areas and propellers. These measures are widely expected to save about ten per cent of the fuel consumption (averaged over five-year docking intervals).
Air lubrication has been progressing significantly in industry perception and take-up within less than a decade. As lower speeds and wider ships play in favour of air lubrication technology, we can expect more such installations in the years to come. Net savings of five to ten per cent on shaft power have been proven in third-party performance monitoring.
Lower ship speeds also favour business cases of wind-assisted ship propulsion (WASP). For commercial shipping, only robust and highly automated systems make sense, combined with dedicated routing systems.
Smart ships of the future
Falling costs for sensors, computing power, and satellite communications make it a safe prediction that ships of the future will have sensors literally “everywhere”; in the hull, main engine, auxiliary machinery, even small equipment. They will also have the computing power to process most data directly (Edge computing), escalating resulting information and insight selectively when needed.
The Internet of Things (IoT) is turning from vision to reality in our time. The ubiquitous interface problems between thousands of native data formats of assorted original equipment manufacturers are gradually overcome through industry standards, a sometimes still reluctant opening due to customer pressure and smart data adapters.
Future ships will have more complex energy systems, typically featuring a mix of diesel engines, electrical systems with fuel cells and batteries, and WASP. There will be smart software support (“digital twins”) to manage these complex machinery systems optimally, both in design and in operation.
The wealth of data coming from onboard sensors and external sources can be used to build digital twins for assorted applications, often combining artificial intelligence (AI)/machine learning (black-box models) and first-principle simulations (white-box models).
Besides onboard sensors, ships of the future will have access to a mix of external sources to complement information for enhanced situational awareness, such as satellites, low-cost oceanographic drones, and aerial drones in port.
Several ICT technologies contribute to easier maintenance of future ships. Remote inspection schemes will become standard, whether based on permanent onboard cameras, aerial drones, or underwater drones. In any case, machine vision based on AI will be used to detect occurrence and degree of deficiencies.
Performance monitoring will enable predictive maintenance in most cases, reducing unplanned ad-hoc maintenance work by the ship’s crew. Condition-based maintenance systems may diagnose eventual problems at an early stage and support the fixing of the problem, for example by ordering spare parts, preparing 3D printing, or guiding repair by ordinary persons using embedded expert systems. Along with reduced workload in the engine room due to cleaner fuels, this will allow further reductions in crew sizes.
Unavoidable repair on board ships, as well as advanced maintenance, will be facilitated by augmented reality (AR), allowing intuitive instructions making highly specialised expertise obsolete. While current AR applications in the maritime industry are largely based on tablets, within a decade, head-mounted devices (successors of the current Microsoft HoloLens) will become standard, allowing hands-free operation. Instructions will be either coming from embedded expert systems or live via headphones from shore-based experts. In sum, the maintenance friendly ship of the future will support further reductions in crewing.
Unmanned shipping to remain a vision
The vision of unmanned intercontinental cargo shipping will remain largely a vision in my lifetime, as legal and economic hurdles stand in the way of the vision rapidly becoming reality. Even if main machinery systems will need less maintenance and repair, the multitude of other systems on board will make crew-based maintenance strategies more attractive than alternative options.
However, autonomous technology will progress both in scope and capability of systems. For selected applications, we will have unmanned, autonomous ships (for instance short-distance ferries or dedicated short sea cargo shipping), and remote-controlled ships (such as tugboats and fire-fighting vessels).
For most cargo ships, we will have low-crew smart ships (with automatic collision avoidance, automatic berthing, self-monitoring for hull, engine, and cargo, ability to sail autonomously for limited time in certain conditions, and so on).
Picture: About 200 participants travelled to Rotterdam on 11 May for the KNVTS symposium.