The Baltic Sea maritime corridor has become a global testbed for carbon-neutral ferry operations through the TT-Line and Everllence partnership. By utilizing regional Northern European agricultural waste for bio-LNG production, the project leverages existing gas grid infrastructure to deliver 100% CO2-reduced fuel to the 230-meter “Green Ships” Nils Holgersson and Peter Pan. This geographical integration proves that local circular economies can successfully decarbonize high-traffic shipping routes without additional engine modifications.
Germany | March 9, 2026 – German ferry operator TT-Line has revealed a major milestone in maritime decarbonization, confirming that its next-generation Ro-Ro passenger vessels, Nils Holgersson and Peter Pan, successfully operated on bio-LNG throughout 2025.
The initiative, conducted in close partnership with Everllence PrimeServ Germany, has demonstrated that climate-neutral operations are achievable using existing dual-fuel engine technology without compromising performance or mechanical integrity.
The Fleet: Engineering for the Future
The two 230-meter “Green Ships,” commissioned in 2022 and 2023 respectively, serve critical routes across the Baltic Sea, connecting Germany, Sweden, Poland, and Lithuania. Both vessels are equipped with a sophisticated power plant consisting of:
- 2 × 8L51/60DF Everllence engines
- 2 × 6L51/60DF Everllence engines
The collaboration involved nearly a year of continuous onboard emission measurements on the Nils Holgersson. The data collected by Everllence PrimeServ provided three critical technical breakthroughs for the bunkering industry:
- Zero Performance Degradation: No negative influences were found on engine operating parameters during bio-LNG combustion.
- Methane Slip Stability: There was no significant “aging effect” on the engines related to methane emissions.
- Lab-to-Sea Consistency: Emission values recorded on the test bed were successfully reproduced during real-world maritime operations.
The Logistics of Bio-LNG Bunkering
The bio-LNG used by TT-Line is sourced from agricultural waste in Northern Europe. The process follows a “grid-to-ship” pathway:
- Biogas is fed into the existing regional gas grid.
- The gas is then extracted, liquefied, and loaded onto a dedicated bunker vessel.
- The bunker vessel delivers the climate-neutral fuel directly to TT-Line’s fleet.
The Environmental Impact: Replacing a single tonne of fossil LNG with bio-LNG saves 2.75 tonnes of CO2, representing a mathematical 100% reduction in carbon emissions for that fuel volume.
Executive Perspectives
Andreas Schaerli, COO of TT-Line “With the use of climate-neutral bio-LNG, which is obtained from waste materials, TT-Line is making a decisive contribution to climate protection on the Baltic Sea. Thanks to this technology, our Green Ships enable a CO2-free journey throughout the entire fleet. Our customers can already fully compensate for their crossing by adding bio-LNG during the booking process. We are thus consistently focusing on innovative solutions to sustainably reduce emissions.“
Dr. Michael Filous, Senior VP and Head of PrimeServ Germany, Everllence “The key benefit associated with bio-LNG is the reduction in CO2 emissions. A major advantage for the customer is that while there are specifications that the fuel gas needs to fulfill, such as methane number, no additional engine works are necessary as long as the fuel gas meets the specifications. Indeed, this was the case for the Nils Holgersson.”
Administrative Innovation: The “Pooling” Process
TT-Line is leveraging a process known as pooling to maximize the administrative impact of their renewable fuel uptake. This system allows the emission savings achieved on specific vessels to contribute to the reduction of the entire fleet’s average emissions in the Baltic Sea.
These savings are verified through certificates issued by the fuel supplier, documenting the precise GHG reduction compared to conventional fossil fuels. This structured approach provides a clear audit trail for regulatory compliance and corporate sustainability reporting.
About TT-Line
TT-Line, the market leader in ferry transport between Germany and southern Sweden, With nine modern ferries and up to 18 departures daily, the company links the German Baltic ports of Travemünde and Rostock, the Polish port of Świnoujście, and Klaipėda in Lithuania with the Swedish hub of Trelleborg.
Since 1962, TT-Line has transported millions of passengers and freight units, currently handling approximately 1 million passengers, 250,000 cars, and 500,000 freight units annually. The company remains a leader in environmentally responsible ferry transport and continues to expand its Green Ship fleet to meet future sustainability goals.
About Everllence
Everllence is a global leader in decarbonization and propulsion systems for shipping, energy, and industry. the company’s portfolio spans advanced engine technology, climate-neutral fuel retrofits, carbon capture, hydrogen systems, and industrial heat pumps. Through its subsidiary Quest One, Everllence also supports green hydrogen production at scale. With 15,000 employees across more than 140 sites worldwide, Everllence’s service arm, Everllence PrimeServ, provides global after-sales support.
Source: Everllence