Issuing agency: Bureau Veritas Marine & Offshore
Column:Future Fuel
source: https://marine-offshore.bureauveritas.com/shipping-decarbonization/future-fuels/hydrogen
To reach net-zero shipping, the maritime industry will need a secure supply of fuels that are carbon free or carbon-neutral from a well-to-wake perspective. Hydrogen has the potential to be such an option, and interest from shipping companies is growing. But fulfilling this interest would require vast amounts of green hydrogen (produced using renewably-sourced electricity). Production and supply are not yet available at the necessary scale, but the groundwork is being laid around the world.Many countries are currently establishing roadmaps to transition industries to hydrogen fuels. In Europe, the Alternative Fuel Infrastructure Regulation (AFIR) and FuelEU Maritime will mandate the supply of low-carbon fuels in ports, which should encourage the development of bunkering facilities for hydrogen.As for use on ships, some obstacles remain. For example, internal combustion engines suitable for hydrogen fuels are still at the demonstrator stage. However, hydrogen fuel cells are a mature and available technology and could be a solution for some vessels. If these challenges can be overcome, hydrogen could be a key fuel to help the maritime industry reach the IMO’s target of net zero by (or close to) 2050.
Green hydrogen is sourced from the process of electrolysis which relies on renewable electricity to split water (H2O) into hydrogen (H2) and oxygen (O2).If owners can secure a supply of green hydrogen, it could be used to decarbonize a range of operations for different types of ship from navigation to auxiliary power. For example, inland navigation vessels and short-sea ships are well-suited candidates for onboard hydrogen fuel cells. Meanwhile large vessels – like cruise ships or container ships – are most likely to harness hydrogen as a power source while at berth.
Julien Boulland Global Market Leader, Sustainable Shipping
The industry must focus on developing safety measures and storage solutions before hydrogen can become a viable and scalable fuel solution:
Bureau Veritas has a long history of developing Rules for gas-fuelled ships. We helped pioneer the solutions for the transportation and use of liquefied natural gas (LNG) as a fuel in shipping. We are now participating in several collaborative R&D projects, such as the EU-backed LH2CRAFT, which aims to find innovative and sustainable technologies for the storage and transportation of hydrogen.
We have been an early mover in this field, releasing our NR 547 Rules for ships using fuel cells in 2022, and our NR 678 Rules for hydrogen-fuelled ships in 2023. The latter are informed by the experience of land-based industries to provide requirements until an international regulatory framework is implemented.
Bureau Veritas Group is present across the entire gas value chain, championing safe practices for sustainable energy sources. Our certification scheme for renewable hydrogen aims to promote transparency in the production process, and verifies that the fuel has a carbon footprint below 2kg CO2 equivalent per kilogram.
Further research is needed before ship owners can take full advantage of the benefits of hydrogen fuel – and this may take some time. As a zero-carbon fuel, hydrogen is potentially a good candidate for compliance with various regulatory requirements. However, current technological maturity and fuel availability limitations pose challenges to the wide-spread use of hydrogen fuel.
Fueling a ship with hydrogen has significant implications for both capital expenditure (CAPEX) and operational expenditure (OPEX). From a CAPEX perspective, ships would need to be equipped with suitable storage tanks and power systems. In OPEX terms, the cost of hydrogen fuel is difficult to predict far into the future, but it may be high due to competition from other land-based industry, and the mobility sector in particular.
Hydrogen fuel is generally stored in one of two ways, either as compressed hydrogen gas or as liquid hydrogen. To achieve compressed hydrogen, the gas is pressurized at or above 250 bar to reduce storage tank size requirements.In liquid form, hydrogen must be stored around -253°C in cryogenic tanks. Both options reduce the overall volume of hydrogen, making onboard storage options more viable for ships.
On a tank-to-wake basis, hydrogen is considered carbon-free as it cannot generate CO or CO2 as a by-product (however, some NOx by-products can be produced with engines). With that said, not all hydrogen is sustainably produced; most is currently of fossil origin, using coal and oil. The only truly zero-carbon hydrogen fuel – called green hydrogen – is produced by renewably-sourced electricity via electrolysis.