A transition towards renewable and low-carbon gases in the shipping sector—and international shipping in particular—is complex considering the long lifetimes of ships, large fuel storage demand, low operating margins, and the need to have matching fuel options on each port the ship bunkers. In January 2020, the International Maritime Organisation (IMO) issued a regulation to limit the sulphur mass content of fuel oil to 0.50%.133 The IMO put forward adoption of low-carbon fuels as a way to achieve 2030 and 2050 decarbonisation targets. The attention to fuel types and resulting SOx emissions will add to ongoing discussions on the fuels used in the shipping sector in the future; the sector is also aiming to cut CO2, NOx, and particulate matter emissions.134
3.2.2 Growing use of LNG and hydrogen in pilot stage developments in shipping
LNG use in shipping is growing, and several pilots are ongoing to test the maritime applications of hydrogen fuel cells, mostly in Northern Europe. Multiple low-carbon and renewable fuel options, such as hydrogen, biodiesel, ammonia, and methanol, are in an early development stage in the shipping sector.
The number of ships using LNG has been growing in Europe, reaching 160 vessels in operation and 115 LNG-ready vessels in 2019 (Figure 3.14).135 This growth is driven in part by the development of LNG carriers, which use LNG for their own propulsion, and is facilitated by the large EU LNG import capacity and the EU TEN-T regulation.135 LNG offers a decarbonisation route when bio-LNG is progressively blended into it. Although data on bio-LNG in shipping is not available, recent projects indicate that market interest is growing. The EU LNG import capacity is sufficient to meet 43% of total 2015 natural gas demand; in recent years, only 10% has been utilised for imports.136 LNG import locations are mainly located in the North and South Western parts of the EU, mostly located close to or in existing port areas with key shipping routes.
No statistics are available on the amount of biomethane used by LNG ships. LNG is imported from port locations around the EU (i.e. close to where demand from ships will be). Some developments are ongoing, with the Port of Gothenburg offering bio-LNG services137 and other port areas in Germany, Belgium, and the Netherlands introducing bunker barges for bio-LNG.138 Despite these early developments, the availability and costs of biomethane are still considered to be a bottleneck for wider adoption.139
Supported by the TEN-T regulation, LNG bunkering facilities for ships are being established across the EU.
A network of LNG bunkering facilities is being established as part of the alternative fuel recharging and refuelling station development, which is supported by TEN-T regulation; this development builds on existing infrastructure and expands it to cover additional areas in the EU. Figure 3.15 shows LNG bunkering facilities in the EU in 2020. These facilities include LNG bunkered from an LNG import terminal, from storage tanks onshore, or on barges or trucks carrying LNG supply. Ships entering these locations will likely be the first to make the switch to LNG and will have the opportunity to increasingly adopt liquified biomethane when it comes available. The amount of seagoing ships using this LNG infrastructure is growing.135
Hydrogen-based shipping is still in an early commercial phase, with projects being deployed mostly in Northern Europe and limited to small vessels or using fuel cells for auxiliary equipment power.
Hydrogen use in shipping is gaining attention,140 although current developments are mainly limited to smaller scale and pilot projects. Other fuel options exist as well, such as using synthetic methanol and ammonia in shipping. These fuels benefit from having a higher energy density than hydrogen and offering more energy efficient fuel storage.
The interest in hydrogen for shipping is not new. Over the past 20 years, hydrogen use has been limited to relatively small, in-land, near-coastal vessels and ferries, often at a demonstration level without the intention to develop towards commercial maturity. The exemption is using fuel cells in some types of submarines. These have been operated for over a decade by the German and Italian navies for silent, underwater operations.141 The total use of hydrogen in the shipping sector is still limited and no statistics are available on hydrogen consumption or bunkering facilities. Despite the current early commercial phase, larger vessel sizes are being considered and developed, including the use of hydrogen as auxiliary power on large cargo and cruise ships.49 Hydrogen can be blended with conventional fuels in internal combustion engines, but most developments focus on using hydrogen in fuel cells because of better fuel efficiency.
Key areas of research, development, and pilot testing include safety aspects related to handling hydrogen as a maritime fuel, using liquified hydrogen, and improving the weight and strength of pressurised hydrogen storage containers. Liquefied hydrogen comes at relatively high additional energy cost (+30%) and hydrogen will boil off during operation.142 One solution could be using the boiled-off hydrogen to propel the ship. Due to these barriers, hydrogen use in shipping can be expected to develop first in short distance, specialised vessels, such as ferries and maritime maintenance vessels.
Several projects are being launched to reduce the beforementioned barriers and to improve the experience in organising the full supply chain from hydrogen production to bunkering and use as a maritime fuel (see showcase projects in section 3.2.4).