HySeas III – asking the right questions

It’s the final part of a three-part research program that began in 2013. HySeas I examined the theory of hydrogen powered vessels. HySeas II, which ran over 2014 and 2015, involved a detailed technical and commercial study to design a hydrogen fuel cell powered vessel.

HySeas III builds on the first two projects by aiming to demonstrate that hydrogen fuel cells can be integrated with proven marine hybrid electric drive systems, and that hydrogen can be stored and bunkered on board a vessel. The project has constructed a full-sized drive train in an onshore facility near Bergen, Norway.

The project is jointly funded by the EU’s Horizon 2020 programme and the Scottish Government. It’s being co-ordinated by the University of St Andrews in Scotland and involves a consortium of partners:

• Arcsilea Ltd
• Ballard Power Systems Europe
• Caledonian Maritime Assets 
• Deutsches Zentrum Fur Luft- Und Raumfahrt 
• European Ferry Company
• Interferry
• Kongsberg Maritime
• McPhy Energy
• Orkney Islands Council

The global maritime industry is responsible for around 2.2 per cent of the world’s CO2 emissions and 2.1 per cent of greenhouse gas (GHG) emissions each year. In 2018, the Marine Environment Protection Committee (MEPC) adopted an initial strategy to reduce GHG emissions from ships, with the goal of achieving a 50 per cent reduction by 2050, and ultimately phasing them out entirely. 

The HySeas project brought together several different organisations examining the use of hydrogen as an alternative, emission-free fuel source. Its goal is to explore and develop a hydrogen-based propulsion system and to design a new ferry vessel, which will operate between two of Scotland’s Orkney Islands, to accommodate it.

HySeas III project is funded by the European Union’s Horizon 2020 program under Grant Agreement 769417, of more than €7 million. The overall project budget is more than €10 million.

Ferries provide regular, predictable services, usually over short distances. That makes the challenge of linking new onboard technologies with onshore infrastructure a little easier. Routes are often operated by state-owned companies or tendered by governments, allowing direct government support for new technologies that would not be easily adopted because of higher costs. That means ferries make a good testing ground for new technologies aimed at reducing greenhouse gas emissions in the maritime industry.

The consortium partners have created a full-size propulsion system made up of six 100 kW Ballard HD-100 fuel cells, 400 kW of lithium-ion batteries, multidrives with DC converters, inverters and grid converters, switchboards, transformers, hydrogen storage, load banks (simulating thrusters) and a suite of safety equipment. The system is now in place in an onshore facility in Norway, and is undergoing extensive ‘string’ testing to ensure all component parts work safely and efficiently. 

Design of the vessel is ongoing and will be further informed by the results and findings of the string test. 

A propulsion ‘string’ is a series of connected electric modules (hydrogen fuel cells, lithium batteries and power electronics) that generate power to a vessel's propellers. A string test aims to verify their functionality and capability as well as addressing safety, risk and redundancy issues

A hydrogen fuel cell uses the chemical energy of hydrogen to produce electricity cleanly and efficiently, creating only water and heat as by-products. They can operate at higher efficiencies than combustion engines and convert chemical energy to electrical energy with efficiencies of up to 60 per cent. 

A fuel cell consists of two electrodes — negative (anode) and positive (cathode) — sandwiched around an electrolyte. Hydrogen is fed to the anode, air is fed to the cathode. A catalyst at the anode separates hydrogen molecules into protons and electrons, which take different paths to the cathode through an external circuit, creating a flow of electricity.

According to recent research from the International Maritime Organisation, reducing sulphur emissions from fossil fuels like diesel should effectively reduce the chance of 570,000 premature deaths globally between 2020 and 2025. Local environmental improvements from implementing a hydrogen ferry in the Orkney archipelago will not only be measured by cuts in greenhouse gas emissions, but also by cuts in noise emissions.

There is a risk-based approval process that aims to identify all the hazards associated with new technologies on board vessels, and to figure out ways to mitigate those risks to acceptable levels before internationally agreed rules are finalised. The process is well established for recent advances in LNG, methanol and batteries, however IMO approval of interim guidelines for fuel cells (not including hydrogen) was delayed due to the Covid-19 pandemic. 

That means the regulatory landscape surrounding the implementation of fuel cell technology is not yet complete. Regional and national legislations are being developed in most countries, particularly regarding hydrogen as a fuel, and other initiatives are being undertaken for further work in this area. Which means we expect that, by the time the ferry is in operation, the regulatory landscape will be much more developed, if not finalised. 

For the moment, we expect the HySeas III hydrogen/electric drive train to be classed according to classification notation ´Hybrid Power (+)´. On completion of the string test the expected approval will in principle be for the multidrive, the energy management system and the safety system.  

There are some hydrogen gas safety issues operators need to be aware of and be prepared to handle, such as:

• Hydrogen’s wide explosive range compared to other fuels 
• Hydrogen burns with an invisible flame 
• You cannot smell, see, or taste hydrogen 

However, in some respects it’s a safer alternative to fossil fuels. Escaped hydrogen, for example, is non-toxic and will disperse quickly in the atmosphere. Given good ventilation, therefore, the risk of ignition is minimal. Escaped fossil fuels and gases, by comparison, pool at ground level where ignition is more likely.  

Similarly, if hydrogen does ignite, the flames emit low radiant energy, so they’re less likely to spread. Hydrogen in the air is also less combustible than gasoline — gasoline in the air is flammable at a 1.4 per cent concentration limit. Hydrogen’s limit is 4 per cent.

Several precautions were prepared through risk-based design and HAZID workshops, like onboard leak detection and ventilation systems to prevent leaks from reaching flammable levels. Further safety measures include fire detection via smoke or heat detectors and pressure-relief devices to vent fuel cells. 

A small leak will trigger an early warning to allow operators to stop and position the vessel advantageously while it’s still safe to do so. Safety systems are also designed to activate a “safe shutdown” sequence that locks the high-pressure hydrogen in the tank and isolates the high-voltage components from the system.

Simply, to make sure the system works. We need to test functionality under normal conditions and attempt to replicate and test as many scenarios as possible to ensure the drive system will work safely and efficiently under all circumstances. 

We must ensure everyone involved in the system and its supply of hydrogen have all the knowledge and training they need to operate it safely and that everyone knows how to respond to emergencies or technical difficulties. Once we have done that, we’ll be able to finalise the design of the propulsion system, which will then allow us to feed back into the final design of the vessel.