Everllence Completes First Methanol Retrofit of S90 Two-Stroke Engine

Everllence successfully converted its B&W S90 two-stroke engine to dual-fuel methanol operation—the world’s first conversion of its kind. The company ran successful sea trials with COSCO Shipping Lines’ 20,000+ TEU container vessel: COSCO Shipping Libra. Its 11S90ME-C engine was retrofitted to an 11S90ME-LGIM unit.

“We’re proud to support COSCO Shipping Lines and COSCO Shipping Heavy Industry—and the maritime industry as a whole—in taking this step toward decarbonizing shipping,” said Michael Petersen, Senior Vice President and Head of Everllence PrimeServ, Denmark. “This milestone highlights COSCO’s role as a first mover and presents a path for reducing emissions from Everllence S90 engine vessels. It also showcases Everllence’s capability to deliver large-scale retrofit projects.”

The company’s aftersales division, Everllence PrimeServ, partnered with COSCO Shipping Heavy Industry from concept to execution, delivering the first S90 methanol engine retrofit. The full-scope project included engineering, project management, installation, commissioning, and sea trials. Prior to the official methanol retrofit, Everllence invested in a dedicated 4S90 testbed engine in Japan which was commissioned in early 2025. The testbed validated the engine’s methanol performance under real operating conditions.

S90ME-C engine | Image Credit: Everllence

“While the journey toward full decarbonization will require collaboration across the industry, this achievement demonstrates that large-scale conversions are both technically proven and commercially viable,” said Petersen. “This opens a practical pathway towards accelerating the maritime energy transition together with our customers.”

Retrofitting the COSCO Shipping Libra proved the viability of methanol as a maritime fuel and accelerated the S90 engine’s readiness toward Everllence’s large-bore milestone. Going forward, the company expects significant potential for additional large-bore retrofits, as over 300 vessels worldwide are equipped with S90-class engines. These users represent potential candidates for similar dual-fuel methanol retrofits.

Ethanol-Fired Engine

In late September 2025, Everllence successfully operated its 90-bore ME-LGIM two-stroke engine on ethanol, at all load points, in Japan. Its successful ethanol-running validation provides Everllence with a fully operational engine to document ethanol capabilities for the ME-LGIM platform. Over a decade ago, Everllence developed the ME-LGIM platform with the first commercial engine entering service in 2016 within the methanol-carrier segment. The company leveraged this operating experience by upscaling its methanol burning portfolio in 2021, installing the first ME-LGIM outside the methanol-carrier segment.

175D Engines

In August, Everllence agreed to deliver 14 x 3 x 16V175D-MM high-speed engines to Mazagon Dock Shipbuilders in Mumbai, India, which is building 14 fast patrols vessels (FPVs) for the Indian Coast Guard. Each engine generates 2,960 kW, with the entire order scheduled for delivery between December 2025 – December 2027. The Indian Coast Guard will deploy the FPVs for coastal surveillance, protecting fisheries, search-and-rescue operations, and military missions if needed.

The 175D engine is available in multiple cylinder variants—12, 16, and 20—with outputs ranging from 1,500 – 4,400 kW. It is suited for powering ferries, offshore support ships, tugs, and additional working vessels and other market areas, including superyachts, planning yachts, and naval marine applications, are served by other engine variants. Everllence’s design is also eco-friendly, operating with low fuel-consumption and compliance to the latest exhaust-gas emission standards. The engine is compatible with future-fuel requirements with biofuels clearances on FAME and HVO.