IN THE relentless hunt to shave greenhouse gas emissions, shipowners and operators are turning to a range of solutions.

Electrification, while not suitable for all ship types, is viewed as an increasingly attractive option, thanks to its ability to both cut emissions and avoid pollution. Maritime electrification comprises two main technologies: batteries and onshore power supply (OPS).

Growing potential of battery power

Lithium-ion batteries have become the battery of choice in the maritime industry, thanks to their higher energy densities and longer lifespan compared to other alternatives. A growing number of ships are opting to use batteries on board, either as part of hybrid configurations or as a sole means of propulsion.

Battery power offers concrete benefits, including better energy efficiency, and operational advantages, such as improved response times and reduced noise and vibrations. Use of batteries also cuts tank-to-wake GHG emissions and air pollution.

However, batteries come with an important limitation: they require much more space than liquid fuels for the same energy storage capacity. As a result, full electric propulsion is not generally suitable for deepsea ships. It can work well for vessels that sail shorter distances, have predictable operational profiles, and stay closer to an onshore grid. Li-ion batteries, if not properly managed, can also pose significant risks, such as thermal runaway, fires and explosions.

Even so, Li-ion batteries are proving an increasingly attractive solution. As the technology continues to mature, uptake is growing across the industry, especially for ferries, offshore supply vessels, fishing vessels and tugs. More than 1,045 battery-powered vessels are in operation, with an additional 560 under construction.

Cutting port emissions with onshore power supply

Another way to reduce emissions for ships at port is by connecting to onshore power. This is especially useful for large ships that cannot be fully electrified at sea.

When a ship is connected to an onshore power source at berth, it can cut its engines, eliminating CO2 emissions and reducing local air pollution, including sulphur oxides (SOx), nitrogen oxides (NOx) and particulate matter. This directly improves air quality in ports and nearby communities. The electricity supplied to the vessel usually comes from the grid, although it can also come from an off-grid source such as port generators or renewable energy plants.

Today, OPS has a strong footprint in Northern Europe, the North American Pacific Coast and east Asia. Supportive government policies and regulations are expected to help accelerate the further adoption of this technology. In addition, as OPS systems must cope with a wide range of ships calling at ports and their respective needs, standardisation is needed to ensure an “any ship, any port” concept. This will place unique demands on both ports and vessels to standardise interconnection voltages, frequencies and connection hardware.

Derisking maritime electrification

Throughout the evolution of maritime electrification solutions, one thing is certain: there can be no compromise on safety and standardisation. Currently, there are no comprehensive international regulations specifically addressing the use of batteries for ship propulsion. As a result, requirements for battery systems on ships are primarily determined by classification society rules.

As a leading classification society, Bureau Veritas helps ensure that maritime battery systems meet rules requirements for onboard equipment. BV also offers relevant notations for battery-powered vessels and OPS to support their uptake and help shipowners meet their environmental goals.

Its technical advisory arm, BV Solutions M&O, also provides services related to energy modelling and risk assessments to help clients make decisions about how to electrify their fleets and find their path to net zero.

Visit the Bureau Veritas website to learn more