The fuel technology transition is underway in the Maritime industry
90% of goods are transported by ships. The greenhouse gases (GHG) emission from this operation represents around 2,8% of global emissions, as such, shipping is by far the most efficient (environmentally friendly) mode of transport. That said, emissions must be reduced by all, so also the maritime industry.
Maritime emissions can be divided into two categories:
- Local emissions consist of mainly NOx, SOx and particulates (PM). These emissions contribute to deterioration of human health, and loss of wellbeing. They also have short term impact on the natural environment (flora & fauna). Impact depends very much on location of emission and the focus is on densely populated areas and sensitive ecosystems
- GHG emissions contribute to global warming/climate change consisting of mainly CO2 and CH4 (methane). The GHG emissions have low to no impact on human health or
the natural environment on short term, and impact is not dependent on location of emission, as climate change is a global problem
The regulatory response to reduce these emissions has been to implement Sulphur Emission Controlled Areas (SECA) to reduce SOx and later Emission Controlled Areas (ECA) to include also NOx. A global sulphur cap of 0,50% was enforced in 2020 contributing to significant reduction in premature deaths.
For the GHG emissions the IMO have established a strategy to reduce CO2 by 20% in 2030, 70% in 2040 and becoming “net zero” by 2050. A new regulatory framework on GHG is adopted, some regulations are in the pipeline or expected to come.
There are continuous ongoing processes, and compliance is “a must” to stay relevant in business. Because of this we see that the alternative fuel uptake in the world fleet is increasing. In 2023, 93,5% of the world fleet was operated on conventional fuels, while 51,3% of ships on order was prepared for alternative fuels.
Emerging fuels and technologies
More than 50% of the ships on order “can use” LNG, LPG, or methanol in dual-fuel (DF) engines. Ammonia and biofuels are also on the horizon and will be an option going forward. That said, there are challenges to overcome bringing these fuels into the market.
Liquid Natural Gas (LNG) has been around and used in DF engines for the past 25 years or so, mainly used onboard LNG carriers, but also installed on other vessel types like car carriers and container liners. While the LNG carriers burn boil-off from the cargo tanks, other ship types must install separate tanks and cryogenic systems bringing the newbuild cost up significantly. Such systems are also space demanding, making it a challenge to install for certain vessel types. As a rule of thumb, running engines on LNG will reduce CO2 emissions by ~25%. The only catch is that, depending on the engine technology, some of the environmental savings will be reduced through methane slip. A clear benefit of a LNG system is that renewable, or e-LNG can be used without major changes to an existing system.
The environmental performance of Liquid Petroleum Gas (LPG) as a fuel is close to LNG with some advantages, both being fossil fuels. LPG is the best dual fuel option for the fleet of LPG carriers. Bunkering is one of the key benefits of LPG with import/export terminals and LPG carriers providing a wide network of outlets improving the suitability of the LPG as a marine fuel which could open for other vessel types as users. With reference to the DNV 2023 version of the Maritime Forecast to 2050, currently 72 LPG carriers are using LPG as fuel, 93 LPG carriers and 4 ethane carriers have been ordered with LPG-burning capacity. In other words, so far only the LPG segment is embracing LPG as fuel. The properties of LPG offer virtually zero particulate emissions, this can have a positive impact on air quality. The main disadvantage associated with the usage of LPG is to do with the storage and safety. To store LPG, you require very sturdy tanks and cylinders. Other challenges might be that if LPG leak as a gas or a liquid, it will quickly evaporate and form a relatively large cloud of gas which will drop to the ground, as it is heavier than air. This requires extended monitoring of tank tops etc. as LPG is highly flammable.
Considering the alternative fuel uptake in number of new orders, Methanol is really increasing its market presence. Methanol is a key product in the chemical industry. It is mainly used for producing other chemicals such as formaldehyde, acetic acid and plastics. Nearly all Methanol is produced from fossil fuels (either natural gas or coal) and therefore holds carbon. We can categorise methanol into five groups: greenfield conventional (grey methanol), carbon capture greenfield (blue methanol, bio methanol, e-methanol with CO2 from combined natural source, and e-methanol with CO2 from direct air capture. Renewable methanol can be produced using renewable energy and renewable feedstocks via two routes: Bio-methanol is produced from biomass. Key potential sustainable biomass feedstocks include forestry and agricultural waste and by-products, biogas from landfill, sewage, municipal solid waste (MSW) and black liquor from the pulp and paper industry. Green e-methanol is obtained by using CO2 captured from renewable sources (bioenergy with carbon capture and storage [BECCS] and direct air capture [DAC]) and green hydrogen, i.e. hydrogen produced with renewable electricity. The price of methanol is increasing sharply based on source and production process. Another important aspect of methanol versus conventional fuels, particularly for the maritime industry, is the energy density. Taking the energy density into account this means that the onboard bunker capacity must be increased to maintain the same bunkering schedule, or shorter sailing time between each bunkering must be considered. The use of methanol in maritime has previously been a choice exclusively for tankers carrying methanol as a cargo (since 2016), but we now see a sharp increase in orders for the containership segment. However, many of these vessels are “methanol ready”, meaning that they don’t necessarily consume methanol as their main fuel.
Ammonia has attracted wide interest as a source of zero emission fuel for shipping. Almost all ammonia in use today is produced from hydrocarbons, and as such offer nearly no carbon reduction. However, green ammonia produced by electrolysis and powered by renewable sources is an excellent source of zero-emission fuel, if NOx emissions are managed appropriately. Today e-ammonia is produced in very limited amounts, and huge investments are needed in relation to providing energy for production, as well as developing logistical solutions to make this product viable. Ammonia can be categorised as “brown ammonia” produced from fossil fuels, “blue ammonia” using fossil sources with carbon capture and storage, and “green ammonia (or e-ammonia)” using renewable electricity. The most likely solution for storing ammonia is to install a pressurized C-type tank at ambient temperature as this will be the most reliable solution. Due to the toxicity and flammability of ammonia, double walled pipelines must be used as secondary containment inside enclosed spaces. Double walled pipelines might also be relevant in open air to control and detect leakages, and to keep hazardous zones to a minimum. As such, the fuel handling system will be very much like the solution for LNG, with associated space demand and costs.
The potential for Biofuels to play a role in the marine sector comes down to availability, encompassing the annual global inventory of bio-feedstocks, the sustainability for those feedstocks, their economic recoverability, compatibility with conversion processes and competition for a limited resource by other industrial and transportation sectors. Biofuels (biodiesel, bioethanol and bio methanol) are inexhaustible, biodegradable fuels manufactured from biomass like starch, agricultural waste, molasses and algae. There are three generations of biofuels, the first generation are based on edible sugar and starch, the second generation comes from plant dry matter or woody biomass, or agricultural residues and wastes, and the third generation from algae and microbes. The advantages of biofuels are carbon neutrality and no sulphur oxides. Biodiesel goes through a relatively simple chemical reaction production process and is normally blended with petroleum diesel to be used in modern diesel engines. Biodiesel holds relatively much oxygen and can contain higher level of impurities, depending on the raw material used it might therefore struggle in cold climates. Renewable diesel on the other hand is fully refined and cracked using petroleum refining technology reducing CO2 emissions by 90%, the fuel is more costly and have less availability. Biofuels might be used as “blend-in” or as biodiesel without major onboard systems conversion.
The energy intensity of producing e-fuels as mentioned above will be a tremendous challenge, for sure it will be extremely difficult to reach the 2050 goals. Based on a study done by scientific organisations in Norway (“Wise use of renewable energy in transport”), it was found that enormous amounts of energy will be needed to replace more than 300 million tons of marine fuels. To produce all mentioned e-fuels, hydrogen is needed. Conversion of electricity to hydrogen represent an energy loss of around 30%. In addition, further 20 to 50 % of the energy will be needed for further processing into e-ammonia, e-Methanol, and e-diesel or for compressing or liquefying the hydrogen itself so that it can be stored and transported. It is estimated that the amount of power needed to abate the maritime industry alone will be 2,7 times the entire EU power production in 2022.
This scenario opens for the possibility to consider use of other energy options, like Advanced Nuclear. For this reason, OSM Thome is currently leading one project under umbrella of the Green Shipping Programme in Norway, and together with 25 Partners we are studying the possibilities for use of Small Modular Reactors (SMRs) onboard the largest emitters (ships) in our industry. OSM Thome is also participating in a second project named NuProShip, which is headed by the Norwegian University of Science and Technology (NTNU). This project is doing a deep dive into available SMR technologies and solutions.
OSM Thome is dedicated to being a premier provider of holistic technological solutions aimed at substantially reducing greenhouse gas (GHG) emissions and mitigating the climate impact within the maritime sector. We remain committed to collaborating with industry partners to identify effective strategies to achieve the IMO decarbonization goals
