Biomethane has been named as one of the best-positioned fuels to reach net zero emissions by a recent study. The joint study by Lloyd’s Register (LR) and A.P. Moller – Maersk (known as Maersk) found that the best opportunities for decarbonising shipping lie in finding new sustainable energy sources. Based on market projections, the study found that biomethane, alcohol and ammonia are the best options.
Energy efficiency is an important tool for integrated logistics company Maersk to reduce carbon emissions. Efficiency measures have positioned the firm 10% ahead of the industry average. However, achieving net zero requires a change in the way deep-sea vessels are fuelled.
“The main challenge is not at sea but on land,” said Søren Toft, Maersk COO. “Technology changes inside the vessels are minor when compared to the massive innovative solutions and fuel transformation that must be found to produce and distribute sustainable energy sources on a global scale. We need to have a commercially-viable carbon-neutral vessel in service 11 years from now.”
Biomethane, ammonia and alcohol have relatively similar cost projections, according to the study, but varied challenges and opportunities. Toft added: “It is too early to rule anything out completely, but we are confident that these three are the right places to start. Consequently, we will spend 80% of our focus on this working hypothesis and will keep the remaining 20% to look at other options.
LR CEO Alastair Marsh added: “The next decade requires industry collaboration as shipping considers its decarbonisation options and looks closely at the potential of fuels like alcohol, biomethane and ammonia.
“This joint modelling exercise between Lloyd’s Register and Maersk indicates that shipowners must invest for fuel flexibility and it is also clear that this transition presents more of an operating expenditure rather than capital expenditure challenge.”
Alcohols such as ethanol and methanol are not a highly-toxic liquid, with various possible production pathways, according to the study, including directly from biomass and/or via renewable hydrogen combined with carbon from either biomass or carbon capture. However, the companies point out that the transition of the industry towards alcohol-based solutions is “yet to be defined”.
Ammonia is carbon-free and can be produced from renewable electricity. LR and Maersk claim the energy conversion rate of this system is higher than that of biomaterial-based systems, but the production pathway “cannot tap into potential energy sources” such as waste biomass. The main challenge for ammonia is that it is highly toxic and small accidents can present huge risks both to staff and the environment. The transition from current to future applications also presents a challenge for ammonia.
On the other hand, biomethane has a potentially smooth-transition, as technology and infrastructure are already in place. The main concern highlighted by the study is so-called ‘methane slip’ – the emission of unburned methane along the supply chain.
According to the research by Maersk and LR, batteries and fuel cells are unlikely to have an immediate role in propelling commercially-viable carbon neutral deep-sea vessels. Shipping is responsible for 2-3% of global greenhouse gas emissions, so the industry has potential to create a net zero economy by 2050.