Internal Combustion Engines Aren’t the Latest Craze, but Could Power Commercial Fishing Vessels for Some Time

A Scania propulsion engine. Image: Scania.

Despite the electric-engine craze, internal combustion engines (ICE) aren’t going away anytime soon. That was the first thought from Alberto L. Alcalá, a senior sales manager in Industrial & Marine at Scania USA Inc., when asked his opinion on the biggest trends in propulsion technology for commercial fishing vessels.

“The reality is that ICE engines will be with us a long time,” Alcalá said.

By “long,” he means decades. He said Scania is planning to continue to offer ICE propulsion technology to buyers through 2050 and “perhaps beyond.”

Scania has made significant investments in new engines capable of meeting more stringent on-road and off-road emissions levels expected to begin in 2027. The company’s DI13 was launched in on-road markets and is coming to the U.S. industrial market at the end of 2025 and the marine business market at the end of 2026, the company has said.

“These engines will offer increasing fuel economy and power never seen on prior generations,” Alcalá said. “Compatibility with (hydrotreated vegetable oil) has been a Scania feature since 2011 and perhaps this could be the best solution going forward to lower CO2 from an economic standpoint. All you have to do is buy HVO fuel. The key is demand for HVO has to increase for supply to meet the need.”

He explained that it’s easy to switch between fuels with no impact to the engine.

Electrification of propulsion can be two to three times the cost of traditional combustion engines, and the level of replacement drives the cost, he said.

There are also numerous decisions to be made: Hybrid vs. battery-electric vehicles, small battery vs. many batteries, simple boost or idle capability vs. continuous battery power for long- or all-vessel usage.

“Is there a business case for an independent operator?” he said. “Probably not without (a) mandate or public funding.”

Paul Leask, executive vice president at Seattle-based manufacturing company Northern Lights, has seen a market grow for options especially around reducing emissions, and he also sees a mix of interest in more efficient propulsion and propulsion that makes the best sense for operators.

“They’re looking for options for things that help reduce their emissions profile. Hybrid is one of the options that’s being looked at, and there are other versions of hybrid out there. Everybody thinks about hybrid as being electric only and that’s not necessarily true,” Leask said.

“There are applications where vessels sit and idle at long periods of time, and when you run one of these giant engines at an idle, it’s not at its most efficient or cleanest operating range, so things like electric-hybrid allow you the ability to shut off the main engine so that it’s not polluting,” he said.

Other options include transmissions with the availability to shut off the main engine and take in power from a smaller generator set or a smaller engine that can help keep propellers spinning and running in a more optimum load range, making the vessel cleaner and more efficient.

“I think there’s a lot of activity in these kind of markets, we don’t know which one’s going to come out on top, but a lot of people are looking for things like this, depending on the application,” Leask remarked.

Karl Hanson, West Coast regional sales manager for Schottel USA, a Louisiana-based manufacturer of propulsion and steering systems for ships and offshore applications, is seeing a big push for greener operations while vessels continue to need larger diesel engines to longer voyages.

“The idea of going to hybrid on vessels is finding a better business case for a lot of vessels that have runs that are shorter to medium, but for vessels that have long runs, hybrid technology is really to get into port and get out of a port—that’s about as useful as it gets,” he said.

Hanson added that many operators are introducing more green efficiencies aboard vessels that include getting vessel operations in “hybrid states” where generators are warmed up before being turned on, or oils are preheated to near engine temperatures before start up.

“There are some basic things that you can do that may be a little more responsible and in keeping with the idea of being green,” he remarked.

Maritime Electrification

Outside of the commercial fishing industry, other maritime segments are moving toward electrification and alternative fuels, as big propulsion makers like General Electric and Siemens AG put out new electric propulsion technologies and governments continue to push for cleaner fuels in shipping.

For example, by 2026, only alternative fuel-powered vessels will be allowed in Norway’s fjords, which are deep, long and narrow seas.

According to the International Maritime Organization, the global maritime industry produces 2.5% of total greenhouse gas emissions. So, it’s natural to expect pressure from governments and environmental groups to continue to mount.

The IMO last year announced a goal of net-zero greenhouse gas emissions from international shipping around 2050.

Growth of electric and alternative propulsion already has been occurring without broader international regulations. The electric ship industry is expected to be worth $14.2 billion by 2030, growing massively from $3.3 billion in 2022. Based on power, the 75-150 kW segment (mid-size passenger ferries are prominent in this category) is projected to dominate market share of electric vessels, according to a report by business-to-business research firm MarketsandMarkets.

In recent years, an increasing number of large vessels also have become electrified.

The Norwegian Yara Birkeland, a 262-foot, 3,527-ton, fully electric autonomous cargo ship, launched in late 2021. A pair of container ships with a 700-TEU capacity when operating only on battery power developed for COSCO Shipping went into service along China’s Yangtze River in 2023.

Crowley, the privately held maritime, energy and logistics company serving commercial and government sectors across the U.S., in June christened the zero emissions eWolf tugboat in San Diego.

The eWolf is being touted as the first all-electric ship assist tugboat in the U.S. The vessel is based at the Port of San Diego, replacing a conventional tugboat that consumed more than 30,000 gallons of diesel per year—with emissions equivalent to 350,000 gallons of fuel—over the first 10 years of operation, according to figures from the Environmental Protection Agency.

It’s significant that Crowley is making an electric push, since it’s a large operator with 7,000 employees around the world, a reported $3.5 billion in annual revenues and 170-plus vessels in operation.

Alternatives

The use of alternatives aside from electric options are another trend Alcalá is watching. He’s encouraged by the development of such propulsion, but again, he believes they won’t push internal combustion out the door anytime soon.

The “reality of using non-diesel-like fuels” and the challenges of alternatives will be similar to electrification issues, with numerous questions he believes must be answered by operators, such as: What is the fuel that’s going to be used? What technology change to an engine or motor is required? Will an electrification strategy be combined with an alternative fuel, for example, a hydrogen fuel cell?

“You get all the cost and complexity of electric plus all the extra cost and complexity of a completely new fuel supply that is gaseous and under pressure,” Alcalá said.

When does he see electrification of vessels fully taking hold and becoming more of an industry standard? He suggested that a big step in that direction will come when public funding is available and the extra cost of conversion can be mitigated.

“Operational efficiencies can offset some cost by lowering fuel consumption,” Alcalá said. “If legal mandates require a solution that requires electrification, then you have to invest to stay in business. And some companies will invest in alternatives to ICE engines because they choose to.”

Other Trends

Beyond the type of fuel powering engines, the vessel operators should be considering operating profiles, according to Alcalá, who believes outboards are another development in the market worth watching.

“This affects new-builds,” he said. “Vessels have to be built for outboards. This also affects the lifespan. Fishermen need to be aware that long-life, high-hour, high-load applications are not to be expected (as) acceptable for outboards. 

This is one reason why Alcalá said commercial fishermen looking to buy or enhance equipment aboard their vessels must think about the operating profile of an engine, which he said is often misunderstood.

“I think the duty cycle or operating profile of an engine is not promoted enough and understood enough,” he said. “I see smaller displacement engines competing at power ratings of traditionally larger engines but with lower-duty cycles. The key is, does the engine have a rating or duty cycle meeting the intended usage? It is important to use a continuous rating if you intend to operate the engine continuously at the rated power and speed.”

Even if a vessel’s annual usage hours aren’t 24/7, 365-days a year, the profile engine use is key, he added. That said, comparing ratings can be difficult, because many manufacturers use different names and often different definitions.

“At Scania our continuous (ICFN) and Intermittent (IFN) both have unlimited hours a year. One is 100% load and speed, 100% of the time approved, and intermittent is one out of every three hours at 100% rated power and an accumulated load factor of 80% or less,” Alcalá explained.

“These are tremendous engine ratings giving fisherman the opportunity to do a lot of work and I get concerned when someone is shopping a much smaller engine with the same power and a lower price, and they don’t realize the engine is rated for 1,500 hours a year and a 25% load factor,” he remarked.

Scania, he noted, offers two other commercial ratings: Patrol Craft Long and Patrol Craft Short, which can be found on the company’s website along with the engine specs, including torque, horsepower and fuel consumption curves. Scania also has a engine comparison tool with charts and tables.

Don Jergler has been a professional journalist for more than 25 years, covering insurance, real estate and more. He spent two decades as a reporter at several daily newspapers, then entered business-to-business reporting. His freelance work has appeared in the Los Angeles Times, Long Beach Post, Orange County Register and numerous B2B publications. He’s currently the Western Region editor of Insurance Journal.