Parallel Session 15 – Renewable Marine Fuels

Thursday 24 October 2024, 11.30-13.00 BRT

Moderator: Camilo Adas (Be8, Brazil)

Speakers:

Panelists (L-to-R): Mario de Luna Barbosa, Marjorie Mendes Guarenghi, Fernando Alberto Gomes da Costa, Camilo Adas, Tom Walsh, Ling Tao.

Selected conclusions and key messages:

  • Marine shipping is the backbone of global trade, responsible for transporting over 90% of the world’s goods by volume and over 70% of global trade by value. The annual consumption of marine fuels is around 330 million tons, and these are all fossil fuels. Around 40% of all products transported by global shipping are fossil fuels themselves (coal, oil, gas). International shipping is responsible for around 3% of all global GHG emissions, but CO2 emissions from the sector are projected to double by 2050 without further actions. The International Maritime Organization IMO published a strategy to reduce GHG emissions from ships in 2023 with the aim to achieve net-zero GHG emissions by or near 2050. By 2030, the aim is to reduce GHG emissions by at least 20% compared to 2008 (striving to 30%); this would increase to at least 70% by 2040 (striving to 80%).
  • Options to decarbonize shipping are a combination of energy efficiency measures (in vessel design, engine technology, alternative propulsion systems, voyage optimization), power assistance, future energy carriers and carbon capture. Only with the latter two, full decarbonization can be achieved. Challenges for creating markets for (marine) biofuels are related to (1) biomass sourcing: local access to biomass for regional supply and certification; (2) biofuel production: regional capability of biofuel production, required investments and dealing with offtake risks; (3) distribution and bunkering: matching supply and demand, certification; and (4) biofuel use: vessel compatibility, safety (for ammonia), leakage (for methane and hydrogen), as well as securing adherence of market actors to the targets and the economic viability for fleets.
  • One of the main challenges to move to new fuels is the low renewal rate of the fleet, with a global average age of 22 years and the average fleet age is actually increasing. Renewal of the current fleet is a complex process, involving high costs and is time-consuming. Retrofitting to adapt to new technologies and fuels is also challenging.
  • Biofuels are mature enough to contribute to the decarbonization targets, some can even be used in existing engines, with little or no modification requirement. On the other hand, it is too early to adopt ammonia or hydrogen; both also have issues of safety and toxicity. Energy density and storage volume are important parameters when considering alternative fuels for the maritime sector, and they impact a vessel’s endurance range and bunkering frequency. Increases in vessel fuel storage capacity to accommodate less energy-dense fuels is expensive and reduces the volume of space available for cargo transport. Several biofuels including biocrude, straight vegetable oil, biodiesel, and HVO exhibit volumetric energy densities competitive with heavy fuel oil (HFO) and existing marine distillates (MGO, MDO). On the other hand, LNG, LPG, methanol, and liquid ammonia have volumetric energy densities that are 36-61% that of HFO, and thus would require two to three times larger fuel storage volume. Hydrogen would even require a six to seven times increase in fuel storage capacity.
  • Wärtsila, one of the major producers of marine engines. They recognize that the decarbonisation of marine and energy industries is accelerating, and no single solution can be applied to all vessels and ports, so multiple fuels and technologies will be needed. As potential future marine fuels, Wärtsila explores biodiesel/HVO, bio-LNG, green methanol, green ethanol, green ammonia and green hydrogen, with some hybridization (through onboard batteries). Their technology is ready to operate on these various fuels, so flexibility can be provided to the market.
  • Despite the role of sustainable biofuels in mitigate transport emissions, biofuels are still under discussion as a means for maritime decarbonization; sometimes they are viewed merely as a short-term alternative. To achieve the decarbonization targets in the marine sector, it is important to recognize sustainable biofuels as accepted and certified fuels by the IMO. The time to contribute to the discussion on the establishment of standards and regulations is now. Aspects which are still under discussion related to LCA and sustainability are the approach for iLUC, default regional emission values, recognition of certification schemes and the inclusion of socio-economic aspects.

New technologies for the maritime industry (from presentation Marjorie Mendes Guarenghi; adapted from MEPC 80/INF 10).