Engine Scavenge Air Boosts Hull Lubrication Fuel Savings

Everllence is readying to introduce its new Engine Supported Air Lubrication (ESAL) solution aimed at improving net fuel savings from air lubrication systems.

The new system uses pressurized scavenge air from the main engine. In contrast, conventional systems rely on electrically driven compressors to pressurize ambient air which is then distributed through dedicated piping and released from outlets along the hull bottom.

ESAL integrates the air supply into the engine architecture itself, thereby eliminating the need for operating the auxiliary compressors. This lowers electrical consumption while improving overall system efficiency. The engine control system continuously monitors and regulates the airflow to ensure safe engine operation while delivering the necessary air supply.

This engine integrated approach can deliver estimated net fuel savings in the range of 3.5%.

The uptake of air lubrication systems has increased over the past few years, particularly for large container vessels and the LNG carriers, so Everllence is initially targeting that market. Applicable engine types currently available or being developed for ESAL (newbuildings or retrofit) are: G95ME-C10.5-LGIM-EGRTC, G95ME-C10.5-GI-EGRTC, G95ME-C9.5-LGIM-EGRTC, G95ME-C9.5-GI-EGRTC, G95ME-C10.5-EGRTC and G95ME-C9.5-EGRTC.

Nikolaos Kourtidis, Director, New Technologies & Market Development, says the engines tend to be relatively similar in the scavenging air pressures, so the turbocharger that is filling the scavenging air receiver will handle approximately the same air pressure. However, ships differ in the air demand and the overall hydrostatic pressure required. Vessels which have relatively shallow draft, such as small tankers or LNG carriers, will not require pressures as high as VLCCs which have a draft of around 21 meters.

Therefore, any project considering an ESAL application will be evaluated and accepted by Everllence on a per-project basis to ensure correct technical conditions and alignment.

Everllence provides the two‑stroke engine design foundation and engine control system functionality required for ESAL integration. Air lubrication system manufacturers remain the customer‑facing entity for owners, operators, and shipyards, with Everllence acting as a technical subcontractor to the air lubrication system makers.

The technology is expected to be available Q4 2026.