Maersk has signed an agreement to install a high-tech "rotor sail" on one of its container vessels, marking the company's first move into wind-assisted propulsion for its ocean fleet.

The 115-foot-tall sail, designed by London-based Anemoi Marine Technologies, will be retrofitted to a 984-foot, 8,700-TEU Lima-class ship. Installation is due in mid-2027, and the system will then be piloted and tested during regular commercial service. While the sail is being piloted, the vessel is expected to operate on Maersk's (OTC: AMKBY) north and south Atlantic voyages — routes where consistent crosswinds in the Atlantic corridor are the operating conditions rotor sails are designed to exploit, since the spinning cylindrical mast generates thrust via the Magnus effect as wind passes across it.

According to Anemoi's specifications, the company typically installs three to five rotor sails per vessel, with each unit saving roughly one ton of fuel per day and around three tons of CO₂ emissions. Shipping carries roughly 90% of world trade and accounts for close to 3% of global greenhouse gas emissions, so even incremental fuel savings per vessel are significant for carriers facing tightening International Maritime Organization carbon-intensity regulations in the coming years.

Maersk says the rotor sail is part of a broader, fuel-agnostic approach to cutting greenhouse gas emissions across its ocean business. The company's current priorities center on scaling lower-GHG-emission fuels such as bio- and e-methanol, expanding its dual-fuel fleet, and improving network and vessel efficiency. Wind assistance fits as a complementary lever: unlike alternative fuels, it requires no new fuel supply chain and can be retrofitted to existing tonnage, which matters for a fleet of several hundred vessels that will keep burning conventional fuel for years.

Other carriers have also explored wind assistance. Earlier this year, CMA CGM began rotations of the sail-assisted Neoliner Origin, a ro-ro vessel calling at the Port of Baltimore.

In 2025, Maersk added 10 dual-fuel methanol vessels and completed fuel-saving retrofits on 230 owned ships and 150 time-chartered vessels. Those efforts helped push the company's ocean Energy Efficiency Operational Indicator (EEOI) to a record low of 10.8 gCO₂e per ton-nautical mile. By 2027, Maersk expects 25 dual-fuel ships in service, eventually reaching 25% of its fleet capable of running on lower-emission fuels.

The company has targeted net-zero emissions by 2040. Whether the mid-2027 pilot's fuel-saving data supports wider rollout across Maersk's container fleet — and whether rotor sails prove practical on large container ships, where deck space for cargo and container-stacking height complicate installations — will be the results to watch once the trial begins.

Source: FreightWaves - https://www.freightwaves.com/news/maersk-unfurls-new-sail-power-for-container-ship