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Refueling Protocols for Medium and Heavy-Duty Vehicles


There are two overarching objectives to be addressed by this topic:

1. Fuelling protocol(s) should be developed to enable the short-term uptake of hydrogen vehicles based on modelling, experimental validation and field tests. These should be able to be used to fill any compressed hydrogen vehicle of >250 litre CHSS capacity, rather than be protocols specific to particular vehicles (for instance captive fleets of a certain vehicle design). Such vehicles include, but are not limited to vans, buses, trucks, coaches, lorries, trains, ferries, boats and other appropriate mobile hydrogen fuelled applications. This should preferably include fuelling to Nominal Working Pressures (NWP) of both 350 bar and 700 bar, but this does not preclude considering other possible NWPs (e.g. 500 bar).

It is possible that one fuelling protocol would not cater effectively for all sizes of CHSS >250 litres, so it is expected that a small number of protocols, relevant to identified CHSS capacities, could be required (for instance from 250 litres to 500 litres, and 500 litres to 1000 litres), if it is not feasible to use a single protocol. If so, appropriate break points for the size of CHSS capacities should be identified for vehicles that would typically use a Heavy Goods Vehicle (HGV) specific refuelling station.

The protocol(s) should cater for fuelling in a wide of range of ambient conditions (e.g. from -40 °C to +50 °C). It should prevent over pressurisation or overheating of the CHSS above 125% NWP, and above +85 °C, to match the capabilities of the on-board storage vessels currently available. This short-term protocol(s) could use 120 g/s as a maximum hydrogen flow rate to avoid inconsistency with current standards, although it would be considered advantageous to explore higher flow rates.

This work should be carried out in conjunction with SAE J2601-2 and other relevant standards organisations (for example ISO TC 197). Where possible, it should further develop and make available publically the protocols developed in previous hydrogen bus projects (e.g. HyFleet-CUTE) or other applicable work (e.g. HyTransfer).

2. A feasibility study should be undertaken into the needs of future protocols, which should include storage technologies for capacities over 50 kg hydrogen. Whilst “light duty” gaseous hydrogen vehicle fuelling protocols are limited to 60 g/s, and currently some “heavy duty” gaseous hydrogen vehicle fuelling protocols are limited to 120 g/s, there is an anticipated need for greater refuelling rates for vehicles with large CHSS capacities.

The suitability of the current maximum limit of 120 g/s proposed in SAE J2601-2 should be investigated, to identify what components limit the refuelling rate, including but not limited to, the nozzle, receptacle, on-board storage vessel(s) and associated valve(s). Design options for enabling larger flow rates to be used should be identified.

A thorough technology review and benchmarking should be performed for both gaseous and liquefied hydrogen dispensing, keeping practicability and technical constraints in mind to identify the most suitable storage technology for applications such as long haul trucks, coaches, trains, sea-going ships, inland barges, hydrogen transport systems, mobile gensets, etc. Careful consideration is needed to ensure acceptability for all vehicle and systems manufacturers as well as HRS equipment manufacturers and infrastructure operators. Whilst not part of the scope of this work, it should be borne in mind that the technology will then need to be able to be standardized with globally defined boundary conditions that do not pose a restriction to safety of operation, speed of fill and suitability for purpose.

This part of the project should also look into appropriate boundary conditions for the fuelling, and make recommendations on whether different conditions to those currently used for vehicles (in SAE J2601, EN 17127 or ISO 19880-1 for example) can be reassessed to enable faster fuelling.

A workshop(s) might be held at the start of the project to, where possible, identify the current approaches being taken or being anticipated for the fuelling vehicles with >250 litre storage.

The outcome of both objectives should be disseminated to the hydrogen mobility and hydrogen refuelling infrastructure sectors in workshop(s) at the end of the project. Findings and recommendations should also be disseminated to the SAE FCEV Interface Taskforce, and ISO TC 197 WG24 as a minimum, and other standardization committees in the field of hydrogen fuelled heavy goods vehicles, boats and trains.

The consortium should comprise partners from the following sectors: HRS suppliers / HRS operators, medium / heavy-duty vehicle manufacturers (not limited to road vehicles) and component suppliers (e.g. tank, nozzle/receptacle) as appropriate, and organisations able to model fuelling events, in order to scope and validate the practical testing. In addition, the participation of Notified Bodies / hydrogen refuelling station authorisers is also recommended.

A suitable medium and heavy duty hydrogen vehicle refuelling station(s) should be made available for this work by one or more of the project partners and should be evidenced at a proposal stage – either existing, or expected to exist before the project starts. Building of a new hydrogen station is not an eligible cost, while the costs toward fitting an existing station with the necessary hardware, for instance to enable precooling of the hydrogen dispensed, to enable a light duty fuelling station with flow limitations of 60 g/s to deliver up to 120 g/s, or, if applicable, to permit fuelling at 500 bar etc. Are considered eligible. A sufficiently instrumented and controllable dispensing system is required, that is capable of dispensing hydrogen at a range of appropriate flow rates, temperatures and pressures for vehicles with various on-board storage capacities.

Links with other relevant FCH 2 JU funded projects should be established, in particular with the trucks or maritime projects when considering where the future for on-board storage solutions for these applications may lie.

It is expected that the project will contribute towards the objectives and activities of the Hydrogen Innovation Challenge (as detailed under section 3.2.G. International cooperation). Promoting international collaboration beyond EU Member States and H2020 Associated Countries is therefore strongly encouraged.

Any safety-related event that may occur during execution of the project shall be reported to the European Commission's Joint Research Centre (JRC) dedicated mailbox, which manages the European hydrogen safety reference database, HIAD and the Hydrogen Event and Lessons LEarNed database, HELLEN.

Test activities should collaborate and use the protocols developed by the JRC Harmonisation Roadmap (see section 3.2.B ""Collaboration with JRC – Rolling Plan 2019""), in order to benchmark performance of components and allow for comparison across different projects.

The FCH 2 JU considers that proposals requesting a contribution of EUR 1.5 million would allow the specific challenges to be addressed appropriately. Nonetheless, this does not preclude submission and selection of proposals requesting other amounts.

A maximum of 1 project may be funded under this topic.

Expected duration: 2 years.

The lack of standardised fuelling protocols that can be used for any medium or heavy-duty vehicle is a significant barrier preventing larger hydrogen fuel cell vehicles from progressing past the back-to-base philosophy and is a major hurdle for both infrastructure players and vehicle manufacturers to develop and deploy standard products. With an increasing number of zero emission buses and trucks expected to be deployed in EU, a validated refuelling protocol (or set of protocols) for vehicles with Compressed Hydrogen Storage System (CHSS) of capacities >250 litres, or >10 kg storage, is needed. This is a prerequisite for meeting the increasing end-user demand for a) hydrogen fuel and b) short refuelling times; it is the key to opening the commercial market for such vehicles and ensuring HRS are able to safely refuel them.

Furthermore, industry consensus needs to be achieved around the storage technology to be used for capacities of >50 kg on-board a vehicle, because long haul heavy-duty vehicles will most likely not be able to make use of 350 bar CHSS (as currently used by municipal vehicles and city buses) due to the large volumes of hydrogen required.

Currently the majority of HRS for compressed hydrogen serve only “light duty” vehicles, i.e. those with CHSS capacities <250 litres. These typically use the SAE J2601 standards for fuelling protocols, or alternatively fuelling protocols based on these, such as the Clean Energy Partnership (CEP) protocol(s). These are typically unsuitable for the CHSS capacities used for medium and heavy-duty vehicles, and often the dispensers are also physically inaccessible to larger vehicles.

SAE J2601-2:2014 includes some information for fuelling vehicles with >10kg of storage and provides boundary conditions for safe refuelling, but it leaves much of the fuelling protocol up to the reader. Whilst this is reasonable for return-to-base applications for fleet vehicles (e.g. buses) known to the refuelling station operator, it is not appropriate for the wider application of vehicles that would require >250 litre storage using different stations, as the current SAE J2601-2 lacks the practical level of detail required for a full standard.

In general, the technical challenge can be grouped into : (a) vehicles with a storage capacity of up to approx. 50 kg hydrogen, some of which are already in existence, and (b) vehicles requiring capacities of over 50 kg hydrogen, which are under development. There is currently no agreed solution available for both of these groups. Whilst the dispenser and refuelling station for different transport sectors may differ, a fuelling protocol for road vehicles, or trains, or boats, with the same capacity of CHSS should be able to utilise a similar fuelling protocol.

A proven protocol or series of protocols, suitable for any hydrogen vehicle with a larger quantity of on-board storage than those of typical light duty vehicles should be developed as part of this project, with the aim of preparing this protocol(s) for acceptance into relevant international standards.

Consensus on the storage technology and specification to be used for large quantities of hydrogen, which will enable the development of refuelling infrastructure and allow free movement of hydrogen powered medium and heavy-duty vehicles, which would otherwise be limited to prohibitively short ranges if required to fill from the same dispensers as light duty vehicles. A feasibility study into, and development of industry consensus on, storage methods, dispensing protocols and the infrastructure-vehicle-interface (e.g. an ultra-high flow nozzle, capable of approx. 500 g/s) will lay the ‘ground stone’ for the development in the heavy duty long haul area, where significantly greater than 50 kg storage can be expected to be needed.

Key benefits of suitable fuelling protocols that the project delivers include:

  • Shorter refuelling times for end-users, resulting in more competitive products (product attractiveness);
  • Non-proprietary protocols over proprietary protocols opens up the EU market for HRS developers and influences the world market heavy-duty segment (competitive markets);
  • Competence development for protocols for important early markets (EU leadership);
  • One common approach to fuelling of large storage systems for different applications (e.g. long-haul trucks, coaches, trains, inland barges, transport systems, etc.) also offers the possibility to create a large enough market for component manufacturers to be able to develop and offer components at attractive prices, something the industry is currently struggling with.

Type of action: Research and Innovation Action

The conditions related to this topic are provided in the chapter 3.3 and in the General Annexes to the Horizon 2020 Work Programme 2018– 2020 which apply mutatis mutandis.