Liquefied biogas could also be ‘a viable solution for the zero-carbon emission era,’ says Jan Schubert, Senior Manager, Sales and Business Development at Nauticor.
At present, Nauticor is awaiting the arrival of the 7,500 cbm-capacity Kairos bunker tanker. Owned by a joint venture between Babcock and Bernard Schulte Management, the vessel is the largest bunker tanker constructed to date and will enter into operation under a long-term charter to Nauticor.
Speaking on the side-lines of the Harbours Review Spotlight greenhouse gas emissions in shipping event held in Copenhagen this week, Schubert told Bunkerspot that Kairos had lifted LNG bunkers in Malaysia and also called at Algeciras on her journey from the South Korean shipyard and she is on track to arrive in the Baltic Sea in early December. It is anticipated that she will undertake bunker deliveries soon after entering operation under charter.
Addressing delegates at the conference, Schubert emphasised LNG’s ‘clean’ credentials in cutting SOx, NOx and PM emissions in comparison to oil-based bunker fuels, and its CO2 emission reduction profile was also more effective.
He referenced a comparison of emissions per fuel (G/kWh) produced by Norway's Marintek which showed that LNG showed zero emissions of SOx, whereas gasoil was 0.4, marine diesel oil (MDO) 0.50% sulphur was 2.0, and residual fuel (.3.5% sulphur) was 13.
Turning to NOx, LNG was 2, gasoil, 8-11, MDO, 8-11, and residual, 9-12. In terms of PM emissions LNG was zero, gasoil was 0.15-0.25, MDO was 0.25-0.50, while residual was 1.5.
Schubert noted that LNG’s CO2 emissions (G/kWh) were 430-480, but this is less than the 580-630 registered by each of the other oil-based fuels.
To further illustrate the point, he looked at the first project of its type to retrofit the 1,036 TEU Wes Amelie feeder containership to dual fuel gas operations. The vessel’s MAN 8L48/60B main engine was retrofitted to a multi-fuel, four-stroke MAN 51/60DF engine in 2017.
The German shipping company Wessels Reederei has since signed a letter of intent (LOI) with MAN Diesel & Turbo for the conversion of three of the Wes Amelie’s sister ships to dual-fuel gas operation.
Schubert said that since switching from operation on MGO to LNG, the Wes Amelie has demonstrated an 86.78% reduction in NOx emissions, a 95% reduction in SOx emissions, an 84% cut in PM emissions and a 31% reduction in CO2 emissions.
Emissions of methane (CH4) had, however, increased, according to Wessels Reederei data.
While still in the early stages of development, liquefied biogas (LBG) can combine the advantages of LNG with an additional reduction in CO2 emissions, said Schubert.
As reported, earlier this week Terntank’s 14,878 DWT Tern Sea tanker was bunkered with 50 tonnes of LNG and 18 tonnes of liquefied biogas (LBG) at the Port of Gothenburg.
Schubert also highlighted Hurtigruten’s plans to fuel six newbuildings with LNG and LBG produced from organic waste, starting in 2021.
While the existing LNG bunkering infrastructure can also be used for LBG, Schubert also highlighted that LBG sourced from organic waste can cut CO2 emissions by almost 100%.
He acknowledged that at this stage in the fuel’s development production quantities are very small and the price of LBG is currently significantly higher than LNG. However, he said, a bunker fuel which is a blend of LNG and LBG can significantly reduce further a vessel’s CO2 emissions over pure LNG.