Powering the future: how battery technology is reshaping maritime engineering

As battery technology transforms the maritime sector, marine engineers must adapt to new skills in energy management, electric propulsion, and advanced diagnostics. This shift presents both a challenge and an opportunity — reshaping careers and redefining the future of ship engineering. Andrew Draper reports

The maritime industry is undergoing a transformative shift as battery technology gains momentum across various vessel types. From ferries to cargo ships, an increasing number of operators are embracing electric propulsion, driven by advancements in battery efficiency and energy storage capacity. This growing adoption is not just a technological leap – it is a response to stricter environmental regulations and a global push for sustainability.

As battery capabilities improve, ships can travel farther and operate more efficiently, reducing emissions and reliance on fossil fuels. With regulatory support and continued innovation, maritime batteries are set to play a pivotal role in shaping the future of cleaner, greener shipping.

The growth in battery-electric vessels is also fuelling demand for specialist maritime labour skills, according to Norway-based industry body Maritime Battery Forum (MBF).

'The jobs on board these ships will change,' MBF managing director Syb ten Cate Hoedemaker says. 'We need more people with knowledge of electric systems, both electrical engineers but also people that have an automation background. Because it's not just the electrical system, it's the control systems that you need to understand and how those work.'

On the upside, engineers will get less dirty from working with this kind of system, Mr Hoedemaker says. 'They're less noisy, so it's more comfortable for sure.'

Electric dreams

Ferry operators in UK waters 'going electric' include DFDS and Brittany Ferries. DFDS announced in May 2024 an investment of €1 billion (£836 million) in six battery powered ships sailing between Dover and Calais/Dunkirk. The first will be in operation in 2030. It said it cannot operate them without access to sufficient power supply on land and infrastructure to accommodate charging facilities in ports.

DFDS says it is working with local authorities on this and with world-leading experts in battery technology, ship design and energy efficiency. The aim is to ensure the design encompasses safety and performance while using production methods with the least possible impact on the environment. Three vessels will be under the French flag, according to DFDS.

Brittany Ferries' new electric hybrid ship Saint-Malo entered service on 12 February, calling into Portsmouth as part of the company's fleet renewal. It runs on liquefied natural gas (LNG), batteries, or a combination of the two.

Saint-Malo's sister ship Guillaume de Normandie will be shore-power capable (though charging will not be available until later this year). The first commercial sailing will be on 18 April, it says.

Norway's Norled ferry operator claimed the world's first all-electric ferry, MF Ampere, built in 2014. Now, half the fleet is battery powered and growing. Denmark's Molslinjen is planning to convert its third ferry to electric later this year.

While ferries are the most popular vessel for electrification due to their short voyages, other vessel types are increasingly adopting battery power too. These include tugboats and bulk carriers. In March, marine battery maker AYK Energy announced an order to manufacture and supply the 6MWh battery that will power the world's first battery-methanol tug for Svitzer. Turkish shipyard Uzmar is building the vessel, with delivery planned in the second half of 2025.

In January, Liverpool-based Bibby Marine announced the signing of a new shipbuilding contract with the shipyard Armon to build an electric commissioning service operation vessel (eCSOV). It will feature a battery system complemented by dual-fuel methanol engines able to run all day with a 24.4MWh battery pack and offshore charging.

According to Mr Hoedemaker, the Netherlands counts some 63 battery powered ships, in a wide variety. There are fully battery powered GVB ferries in Amsterdam, several ferries in Dordrecht, electric ferries Altena XI and Gorinchem XII, the event ship Zilvermeeuw Z9, and some electric workboats. Switzerland counts a handful of passenger vessels, mostly hybrid powered.

A just transition

The MBF counts 86 members, ranging from classification societies to shipping and shipbuilding companies, battery recyclers, as well as manufacturers of batteries and their components. It registered its 1,000^th battery-powered ship in 2023. The number has now risen to 1,500, it says. The ship type and installed battery capacity per ship is also expanding.

The organisation says 20% of ships in its database are fully battery powered though they may have a small back-up generator too.

An important part of MBF's work is education and training. It runs an online introduction to maritime batteries and battery safety. One of the organisation's members is Ocomp, a Norwegian training centre and research institute specialising in maritime safety. It has a particular focus on lithium-ion batteries and safety at sea.

It has trained over 3,000 seafarers in Norway on battery powered ships, according to Mr Hoedemaker. He points out Norway is the only country in the world with crew training requirements on battery powered ships. This was set out by the Norwegian Maritime Authority in 2022.

Mr Hoedemaker acknowledges that seafarers might fear electrification and potential changes to their work it may bring. 'That's something that we as an industry really need to take seriously,' he says. MBF is raising these fears with ship designers, battery manufacturers, and electrical integrators.

'We need to take the seafarers on that journey with us. They need to be aware of the design choices that we make because it will affect their way of working, both for maintenance and operations, but also for safety. Seafarers must understand what they need to do in case of an incident with batteries, which is different than when there is an oil fire on board, for example.'

Part of the energy mix

The UK's Faraday Institution, which undertakes battery research, skills development, market analysis and early-stage commercialisation, issued a report in February on batteries in the maritime industry. It says battery technology will be an important part of the energy mix as heavy fuel oil is phased out.

Batteries offer energy efficiency, reduced emissions and improved performance for smaller vessels, it says. Hybrid fuel solutions are emerging for deep-sea shipping, according to report author Stephen Gifford, Faraday's chief economist. 'As battery technology continues to advance, full electrification is becoming particularly suited for short routes and vessels such as short-haul ferries, coastal ships, recreational boats and inland waterway craft,' he says. Hybrid systems are combining batteries with other fuels to enhance energy efficiency and operational flexibility, he adds.

Faraday predicts that the global market for alternative fuel production technologies for maritime fuels will be worth £8-£9 billion per year by 2050. Citing DNV, a classification society, it says ammonia will be the largest energy source with a 35% share in maritime. E-fuels including e-methanol will take 14%. E-fuels, like e-methane, e-kerosene and e-methanol, are in gas or liquid form and produced from renewable or decarbonised electricity, according to energy company Engie.

Faraday notes the adoption of battery-powered ships has accelerated following modest growth in the past decade. It says the increased efficiency of battery-electric power is significant as the overall energy required is less.

Both Faraday and the MBF say while batteries can serve as the main propulsion source in full battery electric or hybrid vessels, an alternative back-up power source is needed. Hybrid systems with, for example, diesel generators alongside battery systems, are expected to become more widespread as distances travelled grow. Vessels can operate on batteries alone when entering and leaving port, with reduced emissions, and switch to other fuels at sea.

As battery capabilities improve, ships can travel farther and operate more efficiently, reducing emissions and reliance on fossil fuels

Port charging challenges

Battery charging is one of the biggest challenges as there is a lack of shore-side charging facilities. Faraday calls in its report for more investment in port electrification infrastructure, as well as research and industry incentives to support the transition to battery powered shipping.

At Singapore Maritime Week in March, the maritime and port authority of Singapore announced a new safety and technical standard for electric harbour craft charging infrastructure and battery swapping systems as part of Singapore's efforts to decarbonise the domestic maritime sector.

Lithuania's Port of Klaipėda has signed a contract for the installation of ro-ro port charging infrastructure from next year. The Brussels-based European Onshore Power Supply Association (EOPSA) promotes the widespread adoption of onshore power supply as a sustainable solution to reduce noise, vibration and air pollution from using fossil fuel engines in port and port city environments.

Conclusion

Faraday says the UK's established strength in global shipping, alongside advancements in battery technology and the creation of national innovation centres, positions it well to benefit from the shift to new energy fuels and technologies. 'Realising the full benefits of this transition will require coordinated investments in both vessel technology and port infrastructure to enable wide-scale adoption of clean energy solutions,' it adds.