Norsepower, the leading provider of mechanical sails for large vessels, and Idemitsu Tanker Co., Ltd., the shipping arm of Idemitsu Kosan, have announced their agreement to equip two Very Large Crude Carriers (VLCCs) with the Norsepower Rotor Sail™. The vessels, which will be built by Japan Marine United Corporation (JMU) and Nihon Shipyard Co., Ltd., (NSY) mark the world-first release of VLCCs to be fitted with rotor sails. Each VLCC will be delivered with two 35x5m explosion-proof Norsepower Rotor Sails™. The first vessel is scheduled for delivery in end of 2028.
December 02, 2025, Helsinki, Finland: As part of Idemitsu’s commitment to reducing emissions and advancing sustainable transport solutions, the VLCCs have been designed with state-of-the-art energy-saving technologies and prepared for future low-carbon fuels such as methanol. The addition of rotor sails is expected to significantly reduce fuel consumption and greenhouse gas emissions, contributing directly to global decarbonisation efforts in shipping. The project demonstrates how integrating the intelligent, data-driven Norsepower Rotor Sail™ into purpose-designed vessels can deliver exceptional performance gains.
In an official statement, representatives from Idemitsu Tanker Co., Ltd. commented:“Idemitsu Tanker is accelerating the implementation of new technologies and is committed to realizing a carbon-neutral (CN) society by achieving both a stable energy transportation and a reduced environmental impact. By equipping our new VLCCs with the Norsepower Rotor Sail™, we are not only investing in fuel savings and emission reductions but also taking a decisive step towards the decarbonisation of long-haul shipping. This project reflects our philosophy of combining reliable operations with innovation to serve global energy needs responsibly.”
This milestone deal underlines both the maturity of wind propulsion and Norsepower’s leadership in the tanker segment. With 22 units in operation in this segment alone, Norsepower Rotor Sails have already been installed on tankers of various size — from smaller chemical tankers, LCO₂ carriers, MR, LR, VLGC — and now, for the first time, on VLCCs.
Heikki Pöntynen, CEO of Norsepower, said: “This is a defining moment for Norsepower and for wind propulsion in global shipping. Partnering with Idemitsu Tanker and JMU on the first VLCCs with rotor sails and doing so as our first newbuild project in Japan, is a tremendous step forward. Japan has already become the single biggest market for Norsepower projects, and this collaboration confirms both the trust in our technology and its relevance across all tanker segments.”
The Norsepower Rotor Sail™ is a modernised, data-driven evolution of the Flettner rotor – a spinning cylinder that uses the Magnus Effect to capture wind and deliver clean propulsion. Alongside the aerodynamic hardware, each installation is supported by advanced digital control systems that optimise performance in real time, ensuring the sails operate at peak efficiency in every condition. By reducing reliance on engines, the system cuts both fuel consumption and emissions. Depending on wind patterns, routing and vessel operations, Norsepower Rotor Sails typically reduce fuel use by 5–25% — and even higher when conditions are favourable.