Anemoi Marine Technologies is to install rotor sails on two chemical tanker newbuilds under construction for Union Maritime Limited, according to an announcement from the UK-based wind propulsion technology provider.

The 18,500-dwt vessels are being built by Wuhu Shipyard Co in China and will each be fitted with two rotor sails — measuring 3.5m in diameter with heights of 20.5m and 24m respectively. The rotor sails are set to be installed at Wuhu in early 2026 after construction at Anemoi's production facility in China.

The newbuilds will support Union Maritime's strategy of surpassing the 20% reduction in greenhouse gas emissions, based on 2008 levels, required by the IMO's 2030 indicative checkpoint. The use of wind-assisted propulsion will help ensure that the owner fulfills the IMO requirement that at least 5% of the energy used by 2030 is from zero- or near-zero-emission sources.

The rotor sails will be EX-rated, fulfilling the safety requirements for use on vessels carrying potentially explosive substances. Vessel and rotor sail integration design was conducted by China-based ship design and engineering consultancy Odely Marine.

Union Maritime says it selected Anemoi's rotor sail technology for this project following a detailed review of available solutions. Anemoi adapted the previously prepared foundation arrangements to accommodate its system.

"Wind propulsion is central to Union Maritime's sustainability roadmap and to our collaborative initiative, Project AeroPower, which demonstrates that commitment in action," said Bhuvnesh Dogra, Chief Technical Officer of Union Maritime. "Partnering with Anemoi reflects our ongoing drive for scalable, high-impact innovation. We believe Anemoi's rotor sail technology will be a powerful enabler of our goal to build the most energy-efficient fleet on the water."

Clare Urmston, CEO of Anemoi, commented: "We're proud to partner with Union Maritime on these forward-looking vessels. Integrating Anemoi rotor sails from the outset showcases what can be achieved when innovative owners commit to wind-assisted propulsion. This project highlights the strong operational benefits of our technology and sets a new benchmark for efficient, future-ready chemical tankers."

Anemoi's patented technology is designed to harnesses wind power in order to reduce vessel fuel consumption and emissions, including CO₂, SOₓ, and NOₓ. The firm's rotor sail systems are designed for both newbuild and retrofit applications and are claimed to deliver significantly higher thrust per square metre than conventional sails.