Next Generation of Marine Propulsion Uses Smart Tech, Alternative Fuels

f/v Capt. Crunch
The new fishing vessel f/v Capt. Crunch, located in Alaska, is outfitted with twin HTX 30 HamiltonJet waterjets with AVX controls. Photo: HamiltonJet.

The next generation of marine propulsion technologies for commercial fishing boats are following a similar path as their maritime shipping and land-side counterparts, with a focus on efficiency, smart tech and control, and environmentally friendly solutions.

Some of the top companies in the industry have recently announced innovative systems that incorporate artificial intelligence, alternative fuels, and efforts to viably reach zero emissions.


At HamiltonJet, the company’s next generation of products are focused on smart technology and being even more efficient while meeting environmental guidelines in unique and hybrid systems.

At last year’s Workboat Show 2021, Tom Latham, general manager of the Americas region for HamiltonJet, was a featured speaker on a panel discussing emerging technologies and autonomous vessels. In an email, he echoed his Workboat comments and highlighted how the company’s smart control technology aims to future-proof vessels.

“At HamiltonJet, we have always had a sharp focus on developing products designed to assist skippers in their work,” Latham said during panel discussion at the show.

Product features like automatic station-keeping and precision manoeuvring as directed by HamiltonJet’s AVX control system and Jet Anchor option can help with more precise maneuvering, station keeping and vessel control.

The company’s most recent development in skipper assistance tech, JETsense, features smart route-planning autopilot, with vision & radar-based situational awareness for collision alert and avoidance. 

“The system is unique in the way it senses the environment and makes decisions based on what it sees,” Latham said. “We have spent a lot of time on the interface as we wanted something that was as simple to activate at the helm as an autopilot.”  

Launched last year, JETsense is not just an autopilot system, it actually utilizes artificial intelligence and advanced autonomy to survey the surrounding area and make decisions. It can maintain precise control of steering and speed during a voyage, re-route as needed to avoid traffic and obstacles, and provide detailed data-logging and telemetry technology for off-vessel viewing of voyage data, performance data, alarms and diagnostics (access is free during the warranty period and for a subscription after that).

“The interface looks like a chart plotter, with a split-window showing a view of the outside,” Latham explained. “This view is augmented to show objects and other boats as they are being tracked and can be either 180° forward facing or 360° all around. One-touch course keeping is simple, and can be augmented with just collision alert, or both alert and active avoidance.” 

The vessel intelligence system enables modern mariners to do more while out on the water with less work, but the skipper remains in control.

“Once activated, the skipper remains in control of speed using the throttles and can take back control at any time by moving the helm, but the vessel can react to emerging situations itself, if necessary,” Latham explained.

Beyond this, the interface also allows the planning of complex way-pointed routes, accurate grid searches, and even missions that include periods of station-keeping. 

“These features are all standard and provide skippers and their crews the opportunity to grasp the advantages of autonomy: improved safety, productivity and accuracy, while remaining in complete vessel control at all times,” Latham said. “We believe this is merely a glimpse of the future of marine autonomy to come.”

Improved Efficiency

The HTX 30 was the first model to debut within the company’s latest line of waterjets, the new HTX series. The new hydrodynamic design delivers high-speed efficiency, improved corrosion resistance and less wear and tear.

“It offers improved high-speed efficiency and delivers between 5% and 7% more thrust at higher speeds,” Latham said.

HTX jets are also capable of achieving speeds in excess of 55 knots when matched with suitable engines and hull design. Maximum power is 760 HP. 

“In terms of low-speed capability, the HTX 30 features a brand-new cavitation resistant intake and pump design, delivering up to 40% more bollard pull and greater sway thrust than any other waterjets on the market,” Latham said. “This improves maneuvering response, position holding capability, and vessel acceleration. The fully integrated hydraulic system and its components have been designed to be inboard for maximum protection.”

The new design also features 10 times better corrosion protection and a new high efficiency, low-wear steering system.

The new vessel, the f/v Capt. Crunch, located in Alaska, is outfitted with both HamiltonJet’s AVX control system and twin HTX 30 waterjets.

The Capt. Crunch is already making waves within the industry. At lightship, the vessel is reaching impressive speeds of 51 mph and 48 mph under normal load conditions, Latham said.

Lowering Emissions

The recently debuted HamiltonJet EHX Hybrid System offers all the advantages of electric drive with the full capabilities of diesel, Latham explained.

“This unique system delivers lower CO2 emissions combined with the speed, maneuverability, efficiency and safety of waterjets,” he said. “With EHX, we deliver the electric motors, power electronics and control system, alongside specialist expertise to ensure seamless integration with the waterjets, engines, gearboxes or clutches.”

The control system manages the hybrid energy flow between engines, batteries and motors while charging and discharging the batteries as required, Latham explained.

On the automatic setting, it’s as simple to operate as driving a hybrid car. The manual setting offers four different modes of operation—diesel only, electric only, charging or electric boost.

Finnur Fridi
Wärtsilä is supplying a two-speed gearbox for the Finnur Fridi, a modern pelagic fishing trawler currently under construction. Photo: Vardin Group.


To meet marine propulsion trends, specifically for fishing vessels, Wärtsilä is using technology to improve efficiency, control and reliability for work on rough seas. There is a focus on building systems that are in compliance with updated environmental regulations.

The tech team at Wärtsilä has said that it expects an accelerated uptake of drive trains comprised of two-speed gear boxes combined with floating frequency grids.

This system allows for operating at an optimum propulsion efficiency despite the conditions, Wärtsilä Propulsion Technical Sales Manager Tim Cales said in an email.

A two-speed gear box allows the blade of a controllable pitch propeller to be operated near its optimum pitch setting over a wide range of operating conditions, Cales explained. When the power demand is high, e.g., in free sailing conditions to and from the fishing grounds, the high gear ratio can be used. For trawling and/or searching conditions with relatively low propulsion power demands, the lower gear ratio can be selected to avoid the large negative propeller pitch deflection angles that would otherwise be needed.

“These large negative pitch deflection angles cause a suboptimum inflow to the propeller blades and consequently increased noise emissions, elevated risk for the development of cavitation erosion and most importantly a loss of propulsion efficiency. With a two-speed gear box, this efficiency loss can be evaded,” Cales said. “When combined with a floating frequency onboard power grid, a two-speed gear box offers vast flexibility in engine and propeller operating speeds while still being able to generate the required electric load demand by means of a gearbox-driven Power Take-Off (PTO).”

Wärtsilä says that its two-speed marine gearbox offers economic and environmental benefits for vessels having multiple
operational modes or reduced transit speed, including fishing vessels. Photo: Wärtsilä.

In February, the Denmark-based Krossbrekka P/F, a member of the Vardin group, ordered Wärtsilä propulsion solutions for the new Finnur Fridi, a modern pelagic fishing trawler currently under construction.

Wärtsilä is supplying a two-speed gearbox for the 88-meter-long (288.7-foot) trawler, which will work around Faroe Island, Denmark.

The area’s fishing fleet typically operates in harsh sea and weather conditions, so operational reliability is a key issue, Wärtsilä Marine Power Sales Director Johan Hansten said in a statement.

Finnur Fridi will operate with a Wärtsilä 31 main engine, fitted with a selective catalytic reduction (SCR) unit for emissions abatement. Wärtsilä also outfitted the vessel with the shaft generator, a controllable pitch propeller and a shaftline solution. Wärtsilä’s ProTouch propulsion control system, a former winner of the Red Dot Design Award, is providing a comprehensive system of control devices.

The Wärtsilä equipment is scheduled for delivery to the yard in early 2023.

Environmental Regulations

Another trend is focusing on making propulsion systems efficient and compliant with updated environmental regulations.

For fishing vessels operating in U.S. waters, calling on U.S. ports, an important aspect is compliance with Environmentally Acceptable Lubricants (EALs).

According to the U.S. Environmental Protection Agency, vessels are required to use EALs in all oil-to-sea interfaces, unless technically infeasible. The aim is to reduce the environmental impact of oily lubricant discharges on the aquatic ecosystem. Officials hope to achieve this by increasing the use of EALs and maintaining all seals.

There is also a general effort to reduce CO2 emissions in marine propulsion systems, Cales noted.

“Propulsion efficiency has been a key focus for decades, simply because it minimizes fuel expenses for the operator,” Cales explained. “The trick is in finding the right balance between efficiency, propeller-induced noise and vibration levels and the mechanical reliability of the propulsion system”

The International Maritime Organization’s strategy related to reducing greenhouse gas emissions from ships speeds up adapting to more complex, less traditional and somewhat more expensive drive trains, although Cales pointed out that fishing vessels are yet still excluded from the IMO’s targets in regards to the Energy Efficiency Design Index (EEDI), Energy Efficiency Existing Ship Index (EEXI), and Carbon Intensity Indicator (CII).

MAN Engines

The team at MAN Engines noted that marine propulsion is trending toward alternative fuels for CO2 reduction, like renewable diesel, hydrogen and smart hybridization.

MAN Engines spokesperson Florian Schaffelhofer noted in an email that the company is focusing on dual fuel engines for use with hydrogen.

In May, MAN Engines put its first two dual fuel hydrogen-powered engines for work boats into serial operation.

These comprise two twelve-cylinder diesel engines, type MAN D2862 LE448, each with an output of 749 kW (1019 hp) at 2100 rpm. The engines are IMO Tier III-certified and equipped with a Selective Catalytic Reduction exhaust gas after-treatment system. Both V12 engines have been prepared for dual-fuel operation by MAN Engines, and supplemented with a hydrogen injection system by development partner CMB.TECH.

Juergen Haberland, MAN Engines sales director for the American market, pointed out in an email that the low-emission engine is used on the world’s first hydrogen-powered crew transfer vessel (CTV), the “Hydrocat 48” from Windcat Workboats.

For dual operation, an established V12 marine engine is supplemented with a hydrogen injection system, introduced into the charge air via an adapter and added to the combustion cycle.

The combustion process is thereby started according to the diesel principle, which requires the injection of about 5% of diesel fuel, Werner Kübler, head of development at MAN Engines, explained in a statement. The diesel fuel common rail injection parameters have been optimized here for dual-fuel operation.

“MAN Engines has long-standing experience in the development of fuel-saving and reliable diesel engines, including for work boats,” Kübler said. “Building on this experience, we were also able to achieve the best consumption values in dual-fuel operation, and ensure the same operating behavior as displayed by diesel operation at full load. At the same time, we also reduce CO2 tailpipe emissions through the use of hydrogen by an average of approximately 50%, and even up to 80% as a peak value.”

This also makes it easy for maintenance and service, MAN Engines officials noted. The dual system also allows for pure diesel operation to continue without interruption if the hydrogen supply is exhausted.

Smart HYBRID Experience

At Cannes Yachting Festival 2021, MAN Engines showcased the company’s Smart HYBRID Experience to the public for the first time.

“This completely new hybrid system marks a turning point when it comes to modern marine drives, and underlines MAN Engines’ status as pioneers in this technology,” officials wrote in an announcement.

Haberland highlighted four key benefits of the new system: fuel efficiency, performance, comfort (noise, vibration reduction) and MAN as a complete system provider.

The electric motor generator unit from the hybrid system can produce a rated power of 184 kW or 368 kW, at an extremely high efficiency rating of up to 96%. The permanent-magnet synchronous motor/generator is 160 mm long at 184 kW, or 320 mm at 368 kW. Its diameter is 560 mm.

It is positioned on the diesel engine in front of the marine drive and can be separated from the diesel engine by an electromagnetic clutch. This allows the operating mode to be changed without stopping the engines. It can even be done during operation—including as an emergency function—without interrupting the power.

Combined with specific MAN marine engines also allows for enhanced power outputs.

“This enables overall system outputs for each driveline ranging from 474 kW to 1,838 kW (644 hp to 2,500 hp), from the smallest in-line six-cylinder series to the most powerful V12,” officials explained in a statement. “Depending on how the components are assembled, the hybrid system can thus account for up to 56% of the vehicle’s overall power output.”

As Haberland pointed out, with the smart HYBRID Experience, MAN Engines offers a complete hybrid system from a single source. This provides flexibility and attention to the customer’s needs.

“We combine our expertise with the countless technological possibilities at our disposal, providing a MAN Smart HYBRID Experience that is individually tailored to every customer,” Head of Sales Reiner Roessner said in a statement. “To achieve this, MAN Engines makes use of a wide range of technically mature series components. All the possible drive configurations such as V-Drive, IV-Drive, parallel drives and down angle can also be connected to the MAN Smart HYBRID Experience.”

The performance, efficiency and comfort system design principles are tailored to specific applications on the basis of zero-emission, diesel-electric, cross-over, hotel, boost and diesel operating modes.

Expanding the Propulsion Portfolio

MAN Engines recently expanded its existing portfolio of propulsion engines, meeting the emission standard IMO Tier III with five additional power ratings at the lower end of the range, Schaffelhofer pointed out. 

The company is offering a number of additional certified engines of type MAN D2676 for immediate ordering; they are six-cylinder in-line engines with power ratings 290 kW, 331 kW, 368 kW, 412 kW and 441 kW. Including the twelve-cylinder V-engines, the complete portfolio of IMO Tier III engines thus spans a range of power from 290 kW to 1,213 kW (394 HP to 1,650 HP) and thereby satisfies the requirements of working boats for heavy-duty, medium-duty and light-duty operation. These include working vessels like fishing boats.

The solution ensuring compliance with the IMO Tier III emission standards is the MAN Engines’ modular exhaust gas aftertreatment system (AGN), which achieves the emission values simply by using an SCR catalytic converter.

There is a general effort to reduce CO2 emissions in marine propulsion systems, Haberland said.

Regulatory pressure is only one element. Customers are also more willing to invest in CO2 reduced or ZERO CO2 solutions, and there is a self-commitment of MAN Group for sustainability, Haberland noted.

MAN also joined the Scientific Based Target initiative last year. SBTi is a global collaboration that helps companies set science-based targets aligned with the Paris Climate Agreement. Joining SBTi results in MAN committing to science-based targets for reducing emissions.

“Now we have to act in light of the global climate crisis,” Andreas Tostmann, chairman of the board at MAN Truck & Bus, said in a statement. “MAN has achieved a lot in the past and is now taking binding steps to further reduce greenhouse gas emissions that arise in the use of our vehicles, in their production and within the delivery chain. Joining SBTi is a significant step in defining interim targets on our path to greenhouse gas neutrality. We at MAN are therefore pursuing the vision of offering our customers sustainable solutions regarding freight and passenger transport.”

Caterpillar Marine

The next generation of propulsion solutions at Caterpillar Marine is focused on hybrid and alternative fuels.

Expanding Next-Generation Solutions

Caterpillar Marine announced in March its expanded delivery of advanced propulsion and power solutions. The company is incorporating hybrid and electric technology from machine and off-highway products.

The aim is to build advanced hybrid and electric power systems that help minimize customers’ fuel usage, environmental impact and total cost of ownership while maximizing reliability and productivity.

“This is an incredibly exciting time at Caterpillar Marine. Our product strategies have always been shaped by the voices of our customers, and those voices are now steering our system-level solutions as well,” Caterpillar Marine Managing Director Derrick York said in a statement.

Developing Alternative Fuels

Also in March, the company announced development of alternative fuels with an investment in methanol-engine technologies. The move supports decarbonization efforts in the marine industry by offering cost effective methanol-powered solutions without sacrificing value.

“In order to continue supporting our customers with their climate-related goals Caterpillar Marine will continue exploring combustion technologies such as methanol,” York said. “Today’s products are being designed to be upgradable for future methanol utilization, thus further enabling the energy transition.”

Caterpillar Marine also joined the Green Maritime Methanol consortium (GMM), which is studying the feasibility of methanol as a maritime transport fuel. Green methanol can be sustainability produced, easily stored onboard marine vessels, and can provide a near-zero carbon intensity.

“As the pathways to reducing net greenhouse gases from the maritime industry have become more clear, methanol has shown it can play an important role in that future,” York said.

Sara Hall has 15 years of experience at several regional and national magazines, online news outlets, and daily and weekly newspapers, where coverage has  included reporting on local harbor activities, marine-based news, and regional and state coastal agencies. Her work has included photography, writing, design and layout.