Wärtsilä Completes Methane Slip Conversions on Chevron LNG Fleet

Wärtsilä has finalized the first phase of an engine conversion project for Chevron Transport Corporation, successfully retrofitting three LNG carriers with spark gas technology to mitigate methane slip.

The project involved converting one Wärtsilä 50DF engine on each vessel from its original dual-fuel configuration to a spark ignition system. This modification replaces diesel pilot fuel ignition with an electrically controlled pre-combustion chamber valve, creating a more efficient combustion process that reduces the volume of unburned methane escaping the engine during operation.

Targeting Methane Performance

The conversion aims to lower methane slip to approximately 1.1% of fuel use, based on the International Maritime Organization’s weighted E2 test cycle. While this figure is currently an estimated performance level rather than a final field measurement from the three vessels, it represents a specific benchmark for the industry as it faces increasing pressure to address the high global warming potential of methane emissions.

The significance of this development extends beyond the Chevron fleet. Wärtsilä has confirmed that the spark gas conversion is now available to other operators utilizing 50DF engines with diesel-electric propulsion. Because the majority of vessels with this specific engine configuration are LNG carriers, the technology offers a potential retrofit pathway for a substantial portion of the existing global gas fleet to improve environmental compliance and protect asset value without requiring a full engine replacement.

Operational Insights and Future Rollout

Chevron Shipping President Barbara Pickering noted that the project is intended to provide operational insights into greenhouse gas reduction technologies. For shipowners, these insights are critical as regulatory frameworks begin to account for the total greenhouse gas profile of LNG as a marine fuel, including the impact of unburned methane.

The collaboration between Wärtsilä and Chevron is scheduled to continue through 2026 and 2027, with three additional LNG carriers slated for similar upgrades. Once complete, the program will cover six vessels, building on an earlier agreement to evaluate and implement methane reduction solutions across Chevron’s fleet.

Source: Container News