Hanwha Engine builds 'world's first' variable compression ratio LNGC engine

Engine manufacturer and Hanwha Ocean subsidiary Hanwha Engine has built what it calls the world’s first variable compression ratio (VCR) engine for LNG carriers.

Hanwha Engine claims the first commercial 5X72DF-2.2 dual-fuel engine equipped with VCR that it built can can reduce methane slip during operation on natural gas "by up to 50%", with a range of methane slip reduction efficacy running between 30-50%. Methane slip reduction figures cited by Hanwha Ocean are not absolute reductions of methane greenhouse gas (GHG) emissions, but rather reductions in comparison "to existing technologies".

Methane slip is unburned fuel that escapes during combustion cycles in engines, and methane emissions have a shorter lived, but far more potent warming effect on the planet than CO2. 

VCR technology indicates the ability to adjust an engine’s compression ratio in real time in response to operational factors, and in the case of the VCR-equipped engines under construction by Hanwha Engine, the company said the technology is improving fuel efficiency and reducing emissions, including both CO2 and methane slip.

Hanwha Engine said the engine design, developed by Switzerland-based WinGD, underwent a decade of testing and "technology verification" before being built for commercial use in an LNG carrier.

The engine model produced by Hanwha Engine is headed for installation on board one of the LNG carriers under construction at Samsung Heavy Industries for Qatari state-owned oil and gas company QatarEnergy’s LNG extraction from the vast reserves in Qatar’s offshore North Field. The North Field expansion project promises to double the Gulf nation’s LNG production capacity by 2026.