Inboard engine ME-LGIA

propulsionheavy fuel oildual-fuel

Overview
Ammonia-fuelled engines mark a new era in carbon-free marine propulsion. Everllence presents the two-stroke ammonia engine Everllence B&W ME-LGIA, developed to deliver high engine efficiency and reliable performance at sea. The engine is designed for both newbuilds and retrofit solutions and expands the two-stroke dual-fuel portfolio to enable low-emission operation for future fleets.

Development and testing
Building on decades of dual-fuel technology experience, development included single-cylinder tests in 2023 and a full-scale test in 2024. Full-scale engine testing began in November 2024 and focuses on combustion behaviour, emissions, engine tuning, atomizer validation and control system verification; testing was scheduled to continue through mid-2025. The first ammonia-powered ME-LGIA engine is targeted for shipyard delivery in 2026.

Key benefits

• High energy efficiency with low emissions — Ammonia can be used as an energy carrier of sustainable hydrogen and is carbon free. The two-stroke ammonia engine is designed to run with as little as 5% pilot oil at 100% load (L1 rating), with the remaining ~95% of energy coming from ammonia, yielding high power output and low emissions.
• Carbon- and sulphur-free combustion — Ammonia combustion produces no carbon or sulphur emissions, offering a strong candidate for large-scale decarbonization of shipping.
• Flexible retrofit options — The engine is engineered as a newbuild and as a modular dual-fuel retrofit solution for existing electronically controlled ME-C engines, enabling adaptation to different fleet needs.

Design and safety features
The ME-LGIA concept is based on the Liquid Gas Injection (ME-LGI) engine concept and targets the same heat rate as fuel oil mode. Engineering incorporates essential safety features including ammonia containment systems, dedicated sensors, system ventilation and double-walled piping. Auxiliary systems are optimized for safe and efficient operation: an ammonia catch system and absorbers are used to ensure that no ammonia above 5 ppm is vented to the atmosphere at the Research Centre Copenhagen. Selective catalytic reduction (SCR) technology is included to reduce NOx emissions, meet IMO Tier III regulations and eliminate ammonia slip from the exhaust. The SCR system volume and ammonia consumption may be adjusted pending full-scale test outcomes to ensure Tier III compliance.

Specifications

• Model: Everllence B&W ME-LGIA
• Engine concept: Two-stroke, Liquid Gas Injection (ME-LGI) based dual-fuel ammonia engine
• Fuel mode: Ammonia mode and conventional fuel oil mode; aim for same heat rate as fuel oil mode
• Fuel mix (L1 rating at 100% load): ~95% energy from ammonia / ~5% pilot oil (specific pilot oil consumption target achieved at 5% SPOC for L1-rated engines at 100% load)
• Development milestones: Single-cylinder tests (2023); full-scale test (2024); full-scale testing started November 2024 and scheduled through mid-2025
• Targeted first engine delivery: 2026 (1st engine delivery targeted to yard)
• Retrofit capability: Designed as newbuild and modular retrofit solution for electronically controlled ME-C engines
• Safety systems: Ammonia containment, sensors, system ventilation, double-walled piping, ammonia catch system and absorbers (no ammonia venting above 5 ppm at Research Centre Copenhagen)
• Emissions control: Selective catalytic reduction (SCR) for NOx reduction and ammonia slip elimination; intended to meet IMO Tier III