NEW: Rule note addresses safety for ships using fuel cells

Fuel cells – tailor-made for inland waterways?

Jul. 12 2022 - 4 min

Fuel cells convert energy from a fuel source, typically hydrogen (H2O), into electrical energy. This zero-carbon fuel option has huge potential for the inland waterway sector due to vessels’ limited size and power compared to deepsea ships.

A critical moment

The need to decarbonise transport is already a priority for international institutions. Russia’s invasion of Ukraine, and the subsequent increase in global energy prices, has accelerated this drive. At a local level, France, the host of the 2024 Olympic Games, intends to hold the opening ceremony on the Seine River deploying only ‘clean’ ships.

Fuel cell potential

Numerous fuel technologies are being developed that will reduce, or completely eliminate, greenhouse gas emissions from ship operations. But fuel cells offer one of the best efficiency-pollutant ratios.
To date, fuel cells have seen limited application in the marine industry, and installations and components must still be adapted for the marine environment and approved for use on vessels.

However, they offer a particular advantage for inland waterway vessels where the limited power requirement falls within the range of fuel cells, and where vessels are transiting densely populated freshwater areas with a higher need for low air and water emissions.

Principle of fuel cells

Fuel cells convert chemical energy from fuel (typically hydrogen) into electrical energy to create a direct current through the electrochemical reaction with oxygen. No energy is stored in the fuel cell but rather in the associated hydrogen container. When derived from hydrogen, the electrochemical reaction generates no greenhouse gas emissions, and emits only heat and water.

Different types of fuel cell

Depending on the fuel and electrolyte, there exist different types of fuel cell:

  • PEMFC (Proton Exchange Membrane Fuel Cell) is the most commonly used, but uses only pure hydrogen and requires platinum as a catalyst.
  • SOFC (Solid Oxide Fuel Cell) is suitable for heavier power requirements and can use either hydrogen or natural gas, but emits CO2 if natural gas or methanol is used via a reformer. This type of fuel cell is operated at high temperatures (800 – 1000 °C) and requires a significant start-up time.

Challenging conditions

Hydrogen has one of the widest explosive/ignition mix ranges with air, falling at the extreme end as low as 4%. It is highly flammable and explosive. There is a high initial cost of installation, and storage and transport are complex due to hydrogen’s low energy density by volume and special pressure/temperature requirements.

Meanwhile creating hydrogen by splitting water by electrolysis is a costly process. For example, 50-70 kWh of electricity is needed to produce 1 kilogram of hydrogen that subsequently yields only 40 KWh of energy.

Green hydrogen

Fuel cells offer the greatest benefit when hydrogen is derived from a renewable source.

Today we have several classifications of hydrogen from: Grey (sourced from methane or coal), Blue (same sources but with carbon capture), Turquoise (sourced from methane using pyrolysis) and finally Green (sourced from renewable electricity). Fuel cells fuelled by green hydrogen offer a completely clean energy.

Assessing the risk

Bureau Veritas has been an early mover in this space, developing Rule NR547 for ships using fuel cells.

NR547 focuses on the fuel cell system and is to be used in conjunction with several other Rule Notes for alternative hydrogen carriers, including ammonia (NR671), methane (NR529), LPG (NR647), methanol and ethanol (NR670).

Our in-depth technical knowledge helps shipowners and manufacturers design, build and operate their fuel cell systems to the most suitable standards and comply with all regulatory and administrative requirements.

Shipowners and equipment manufacturers must meet specific safety requirements to receive certification for “fuel cell” systems, and a range of risk assessments are required in order to limit the risk of explosion, fire, and the spread of toxic chemicals. These include:

  • A HAZID study of fuel cell spaces
  • A HAZOP study of fuel cell power system
  • A FMECA analysis of fuel cell power installation

These assessments aim to identify and mitigate risks to crew members, passengers, the environment, and the structural integrity of vessels.

The road to sustainability

The market for fuel cells in the marine sector is just beginning but offers enormous potential. Since the earliest days of fuel cell development Bureau Veritas has applied its expertise in vessel safety and system integration to the marine industry.

Our fuel cell Rule note caters for the latest advances in fuel cell technology and incorporates intelligence from industry-wide collaborations. For owners and operators opting for fuel cells, NR547 lays the groundwork for operating safe and sustainable vessels.