MAN Energy Solutions reports that the 1,036-TEU container ship, ‘ElbBLUE’ – the former ‘Wes Amelie’ – has reduced its greenhouse gas (GHG) emissions by 27% by operating on a blend of climate-neutral, synthetic natural gas (SNG) and conventional liquefied natural gas (LNG), compared to LNG alone. Compared with heavy fuel oil (HFO), GHG emission reduction was even as high as 34%. The data has emerged from measurements initially carried out on board the ship in September 2021 when the ElbBLUE became the first container ship worldwide to replace a portion of its bunkered gas fuel (around 50%) with SNG.
Dr Uwe Lauber, CEO of MAN Energy Solutions, said: "With this project, we have proven the technical viability of our concept of the maritime energy transition. Today, more than ever, we are convinced that climate-neutral, synthetic fuels point the way to green shipping – and even further beyond.”
Lauber continued: “The current, global, political situation underscores the future role that synthetic fuels can play in a diversified energy supply in that they point the way toward less dependence on raw material deposits, suppliers and price fluctuations. As a result of the military attack on Ukraine in violation of international law, LNG prices, for example, have risen massively in recent weeks and are now at a similar level to SNG. If production capacity can be built up quickly and synthetic fuels made available to the market, SNG could become a climate-friendly and – in the long term – economical alternative to fossil fuels in shipping.”
Pure SNG to cut GHG by 80%
Stefan Eefting, Senior Vice President and Head of MAN PrimeServ Augsburg, said: “With this pilot project, we have proven that any LNG-powered ship can also operate with green SNG from power-to-X. Even with a blend of just 50% SNG, GHG and pollutant emissions are significantly reduced. When operated exclusively on SNG, we would expect a reduction of at least 80% in GHG emissions for modern ships.”
Gas operation also drastically reduces other polluting emissions compared to HFO. In the case of the ElbBLUE, nitrogen oxide emissions (NOx) dropped by almost 87%, while emissions of sulphur oxides (SOx) and particulates were almost completely eliminated (~99%). These values were achieved in both the exclusive operation on LNG and on a blend of LNG and SNG.
Measurements were carried out on a voyage between Brunsbüttel, Germany and Rotterdam, the Netherlands with SNG comprising approximately 50% of the bunkered gas at 85% engine load. The ElbBLUE is powered by an MAN 51/60DF four-stroke engine. As a multi-fuel engine, the unit allows operation with either HFO or liquid natural gas (LNG) as fuel. The ship's test-run proved that the latter can be replaced by SNG without engine modification.
Owned by German shipping company, Elbdeich, and operated by charterer, Unifeeder, the 1,036-TEU container ship, ElbBLUE, sails the North and Baltic Seas. It made headlines back in 2017 under its former name, Wes Amelie, when its MAN 8L48/60B main engine was converted to the current MAN 8L51/60DF four-stroke unit, which enables dual-fuel operation with gas. This was the world's first conversion of a container ship to multi-fuel operation with climate-friendly LNG.
In September 2021, the ship reached another milestone on the road to climate-neutral shipping when, in the Elbe port of Brunsbüttel, it became the world's first container ship to bunker climate-neutral synthetic marine fuel – some 20 tons. The liquefied SNG was produced in a power-to-gas plant operated by kiwi AG in Werlte, Germany and generated from 100% renewable energy.
Further reductions in methane slip
SNG is considered a carbon-neutral fuel as its combustion releases only as much CO2 as captured during its production using power-to-X technology. However, just like LNG, SNG consists largely of methane (CH4) and, during operation, small unburned quantities of the gas can escape – so-called methane slip. Methane is considered a greenhouse gas that, when released unburned into the atmosphere, is 28 times more harmful to the climate than CO2. MAN already offers solutions for methane-slip-free operation in two-stroke engines. For four-stroke engines, the company is working on various solutions to further reduce the escape of methane from the combustion chamber.
Eefting added: “We have already been able to halve methane slip in our dual-fuel, four-stroke engines in recent years through internal engine measures, and we see further potential in the area of exhaust gas after-treatment. We are currently developing special oxidation catalysts with which we have been able to reduce methane slip by a further 70% in laboratory tests. Next year, we will test the catalyst on board a ship for the first time and expect to have a market-ready technology by 2025.”
Maritime Energy Transition
MAN Energy Solutions has been committed to a Maritime Energy Transition aimed at climate-neutral shipping for many years. From the company's perspective, this requires the industry-wide and massive use of climate-neutral fuels as direct electrification of ocean-going shipping via batteries is not technically feasible. The development and conversion of the infrastructure and global fuel-supply chains required for this can only be successfully achieved in close cooperation between the shipping industry and political regulation, a scenario MAN Energy Solutions vigorously advocates for.