Abstract The paper describes risk assessments case studies undertaken on hydrogen refuelling stations. Several concepts with and without onsite production of hydrogen were assessed. This was done as a task in the EC funded research project European Integrated Hydrogen Project phase 2 (EIHP2). The EIHP2 shall provide input to regulatory activities on an EU and global level facilitating the safe development, introduction and daily operation of hydrogen fuelled vehicles on public roads and their refilling at public hydrogen refuelling stations. Hydrogen specific risk and safety analyses including comparative studies are an important part of the project's scope.
A common methodology for coarse risk assessments that take into account hydrogen specific issues, early concept phase and ensure similar results for the different concepts was adopted.
The main focus of the risk assessments were the hydrogen production elements of six different concepts for hydrogen refuelling stations, five with gaseous hydrogen and one with liquid hydrogen. The risk assessments identified safety aspects, compared the concepts and gave input for hydrogen related standards and regulations.
Conclusions were made regarding the assessed risk levels for the concepts and their comparison with the risk acceptance criteria in form of a risk matrix. The different refuelling station concepts are compared. The risk assessment methodology is also discussed.
Acknowledgement: The authors thank for partial funding from the European through the EIHP2 project Contract: ENK6-CT2000-00442, DNV and Norsk Hydro ASA.
Within the EC funded research project European Integrated Hydrogen Project phase 2 (EIHP2) see ref. /1/, risk assessment of several hydrogen refuelling station concepts were carried out. The EIHP2 project shall provide input to regulatory activities on a European and global level facilitating the safe development, introduction and daily operation of hydrogen fuelled vehicles on public roads and their refuelling at public hydrogen refuelling stations.
The main focus of the analyses was filling stations based on compressed gas, however liquefied systems were also briefly covered. The concepts analysed included hydrogen production by ammonia splitting, methanol steam reforming, natural gas reforming and water electrolysis. Hydrogen supply by truck – gaseous or liquefied – were also analysed. The results presented in this study cover gaseous hydrogen filling stations based on hydrogen production onsite.
The aim of the analyses was to identify hazards and to make a course risk evaluation of the concepts. Initially also the intention was to compare the risk of the concepts against each other and to compare the risk of hydrogen filling stations against the risk of conventional stations. The results were also used as input to development of standards and regulations.
Present at the analyses were technical experts among the EIHP2 partners and external technical experts, dependent on the concept being analysed.