Germany

Clarification of questions of safety represents a decisive contribution to the successful introduction of vehicles fuelled by hydrogen. At the moment the safety of hydrogen is being discussed and investigated by various bodies. The primary focus is on fuel-cell vehicles with hydrogen stored in gaseous form. This paper looks at the safety of hydrogen-fuelled vehicles with an internal combustion engine and liquefied hydrogen storage. The safety concept of BMW’s hydrogen vehicles is described and the specific aspects of the propulsion and storage concepts discussed. The main discussion emphasis is on the utilization of boil-off parking of the vehicles in an enclosed space and their crash behaviour. Theoretical safety observations are complemented by the latest experimental and test results. Finally reference is made to the topic-areas in the field of hydrogen safety in which cooperative research work could make a valuable contribution to the future of the hydrogen-powered vehicle.

An essential problem for the operation of high pressure water electrolyzers and fuel cells is the permissible contamination of hydrogen and oxygen. This contamination can create malfunction and in the worst case explosions in the apparatus and gas cylinders. In order to avoid dangerous conditions the exact knowledge of the explosion characteristics of hydrogen/air and hydrogen/oxygen mixtures is necessary. The common databases e.g. the CHEMSAFE® database published by DECHEMA BAM and PTB contains even a large number of evaluated safety related properties among other things explosion limits which however are mainly measured according to standard procedures under atmospheric conditions.<br/>Within the framework of the European research project “SAFEKINEX” and other research projects the explosion limits explosion pressures and rates of pressure rise (KG values) of H2/air and H2/O2 mixtures were measured at elevated conditions of initial pressures and temperatures by the Federal Institute of Materials Research and Testing (BAM). Empirical equations of the temperature influence could be deduced from the experimental values. An anomaly was found at the pressure influence on the upper explosion limits of H2/O2 and H2/air mixtures in the range of 20 bars. In addition explosion pressures and also rates of pressure rises have been measured for different hydrogen concentrations inside the explosion range. Such data are important for constructive explosion protection measures. Furthermore the mainly used standards for the determination of explosion limits have been compared. Therefore it was interesting to have a look at the systematic differences between the new EN 1839 tube and bomb method ASTM E 681-01 and German DIN 51649-1.

This paper presents a compilation of the results supplied by HySafe partners participating in the Standard Benchmark Exercise Problem (SBEP) V2 which is based on an experiment on hydrogen combustion that is first described. A list of the results requested from participants is also included. The main characteristics of the models used for the calculations are compared in a very succinct way by using tables. The comparison between results together with the experimental data when available is made through a series of graphs. The results show quite good agreement with the experimental data. The calculations have demonstrated to be sensitive to computational domain size and far field boundary condition.

This report commissioned by the Hydrogen Council and announced in conjunction with the launch of the initiative at the World Economic Forum in January 2017 details the future potential that hydrogen is ready to provide and sets out the vision of the Council and the key actions it considers fundamental for policy makers to implement to fully unlock and empower the contribution of hydrogen to the energy transition.

In this paper we explore the role of hydrogen in the energy transition including its potential recent achievements and challenges to its deployment. We also offer recommendations to ensure that the proper conditions are developed to accelerate the deployment of hydrogen technologies with the support of policymakers the private sector and society.

You can download the full report from the Hydrogen Council website here

Deployed at scale hydrogen could account for almost one-fifth of total final energy consumed by 2050. This would reduce annual CO2 emissions by roughly 6 gigatons compared to today’s levels and contribute roughly 20% of the abatement required to limit global warming to two degrees Celsius.

On the demand side the Hydrogen Council sees the potential for hydrogen to power about 10 to 15 million cars and 500000 trucks by 2030 with many uses in other sectors as well such as industry processes and feedstocks building heating and power power generation and storage. Overall the study predicts that the annual demand for hydrogen could increase tenfold by 2050 to almost 80 EJ in 2050 meeting 18% of total final energy demand in the 2050 two-degree scenario. At a time when global populations are expected to grow by two billion people by 2050 hydrogen technologies have the potential to create opportunities for sustainable economic growth.

“The world in the 21st century must transition to widespread low carbon energy use” said Takeshi Uchiyamada Chairman of Toyota Motor Corporation and co-chair of the Hydrogen Council. “Hydrogen is an indispensable resource to achieve this transition because it can be used to store and transport wind solar and other renewable electricity to power transportation and many other things. The Hydrogen Council has identified seven roles for hydrogen which is why we are encouraging governments and investors to give it a prominent role in their energy plans. The sooner we get the hydrogen economy going the better and we are all committed to making this a reality.”

Achieving such scale would require substantial investments; approximately US$20 to 25 billion annually for a total of about US$280 billion until 2030. Within the right regulatory framework – including long-term stable coordination and incentive policies – the report considers that attracting these investments to scale the technology is feasible. The world already invests more than US$1.7 trillion in energy each year including US$650 billion in oil and gas US$300 billion in renewable electricity and more than US$300 billion in the automotive industry.

“This study confirms the place of hydrogen as a central pillar in the energy transition and encourages us in our support of its large-scale deployment. Hydrogen will be an unavoidable enabler for the energy transition in certain sectors and geographies. The sooner we make this happen the sooner we will be able to enjoy the needed benefits of Hydrogen at the service of our economies and our societies” said Benoît Potier Chairman and CEO Air Liquide. “Solutions are technologically mature and industry players are committed. We need concerted stakeholder efforts to make this happen; leading this effort is the role of the Hydrogen Council.”

The launch of the new roadmap came during the Sustainability Innovation Forum in the presence of 18 senior members of the Hydrogen led by co-chairs Takeshi Uchiyamada Chairman of Toyota and Benoît Potier Chairman and CEO Air Liquide and accompanied by Prof. Aldo Belloni CEO of The Linde Group Woong-chul Yang Vice Chairman of Hyundai Motor Company and Anne Stevens Board Member of Anglo American. During the launch the Hydrogen Council called upon investors policymakers and businesses to join them in accelerating deployment of hydrogen solutions for the energy transition. It was also announced that Woong-chul Yang of Hyundai Motor Company will succeed Takeshi Uchiyamada of Toyota in the rotating role of the Council’s co-chair and preside the group together with Benoit Potier CEO Air Liquide in 2018. Mr Uchiyamada is planning to return as Co-chairman in 2020 coinciding with the Tokyo Olympic and Paalympic Games an important milestone for showcasing hydrogen society and mobility.

You can download the full report from the Hydrogen Council website here

Composite cylinders with metal liner are used for the storage of compressed hydrogen in automotive application. These hybrid pressure cylinders are designed for a nominal working pressure of up to 70 MPa. They also have to withstand a temperature range between -40°C and +85°C according GRPE draft [1] and for short periods up to a maximum temperature of 140°C during filling (fast filling) [2]. In order to exploit the material properties efficiently with a high degree of lightweight optimization and a high level of safety on the same time a better understanding of the structural behavior of hybrid designs is necessary. Work on this topic has been carried out in the frame of a work package on safety aspects and regulation (Subproject SAR) of the European IP StorHy (www.storhy.net). The temperature influence on the composite layers is distinctive due to there typical polymer material behavior. The stiffness of the composite layer is a function of temperature which influences global strains and stress levels (residual stresses) in operation. In order to do an accurate fatigue assessment of composite hybrid cylinders a realistic modeling of a representative temperature load is needed. For this climate data has been evaluated which were collected in Europe over a period of 30 years [3]. Assuming that the temperature follows a Gaussian (normal) distribution within the assessed period of 30 years it is possible to generate a frequency distribution for different temperature classes for the cold extreme and the hot extreme. Combining these distributions leads to the overall temperature range distribution (frequency over temperature classes). The climatic temperature influence the filling temperature and the pressure load have to be considered in combination with the operation profile of the storage cylinder to derive a complete load vector for an accurate assessment of the lifetime and safety level.

The use of hydrogen as an energy carrier is going to widen exponentially in the next years. In order to ensure the public acceptance of the new fuel not only the environmental impact has to be excellent but also the risk management of its handling and storage must be improved. As a part of modern risk assessment procedure CFD modeling of the accident scenario development must provide reliable data on the possible pressure loads resulted from explosion processes. The expected combustion regimes can be ranged from slow flames to deflagration-to-detonation transition and even to detonation. In the last case the importance of the reliability of simulation results is particularly high since detonation is usually considered as a worst case state of affairs. A set of large-scale detonation experiments performed in Kurchatov Institute at RUT facility was selected as benchmark. RUT has typical industry-relevant characteristic dimensions. The CFD codes possibilities to correctly describe detonation in mixtures with different initial and boundary conditions were surveyed. For the modeling two detonation tests HYD05 and HYD09 were chosen; both tests were carried out in uniform hydrogen/air mixtures; first one with concentration of 20.0% vol. and the second one with 25.5% vol. In the present exercise three CFD codes using a number of different models were used to simulate these experiments. A thorough inter-comparison between the CFD results including codes models and obtained pressure predictions was carried out and reported. The results of this inter comparison should provide a solid basis for the further code development and detonation models’ validation thus improving CFD predictive capabilities.

In many areas European research has been largely fragmented. To support the required integration and to focus and coordinate related research efforts the European Commission created a new instrument the Networks of Excellences (NoEs). The goal of the NoE HySafe has been to provide the basis to facilitate the safe introduction of hydrogen as an energy carrier by removing the safety related obstacles. The prioritisation of the HySafe internal project activities was based on a phenomena identification and ranking exercise (PIRT) and expert interviews. The identified research headlines were “Releases in (partially) confined areas” “Mitigation” and “Quantitative Risk Assessment”. Along these headlines existing or planned research work was re-orientated and slightly modified to build up three large internal research projects “InsHyde” “HyTunnel” and “HyQRA”. In InsHyde realistic indoor hydrogen leaks and associated hazards have been investigated to provide recommendations for the safe use of indoor hydrogen systems including mitigation and detection means. The appropriateness of available regulations codes and standards (RCS) has been assessed. Experimental and numerical work was conducted to benchmark simulation tools and to evaluate the related recommendations. HyTunnel contributed to the understanding of the nature of the hazards posed by hydrogen vehicles inside tunnels and its relative severity compared to other fuels. In HyQRA quantitative risk assessment strategies were applied to relevant scenarios in a hydrogen refuelling station and the performance was compared to derive also recommendations. The integration provided by the network is manifested by a series of workshops and benchmarks related to experimental and numerical work. Besides the network generated the following products: the International Conference on Hydrogen Safety the first academic education related to hydrogen safety and the Safety Handbook. Finally the network initiated the founding of the International Association for Hydrogen Safety which will open up the future networking to all interested parties on an international level. The indicated results of this five years integration activity will be described in short.

Solutions that simulate hydrometallurgical base metal process streams with high nickel (Ni) and minor platinum (Pt) concentrations were used to create Pt/Ni nanoparticles on TiO₂ nanotube surfaces. For this electrochemical deposition – redox replacement (EDRR) was used that also allowed to control the nanoparticle size density and Pt/Ni content of the deposited nanoparticles. The Pt/Ni nanoparticle decorated titanium dioxide nanotubes (TiO₂ nanotubes) become strongly activated for photocatalytic hydrogen (H₂) evolution. Moreover EDRR facilitates nanoparticle formation without the need for any additional chemicals and is more effective than electrodeposition alone. Actually a 10000-time enrichment level of Pt took place on the TiO₂ surface when compared to Pt content in the solution with the EDRR method. The results show that hydrometallurgical streams offer great potential as an alternative raw material source for industrial catalyst production when coupled with redox replacement electrochemistry.

We demonstrate that the combination of hydrogen release from a Liquid Organic Hydrogen Carrier (LOHC) system with electrochemical hydrogen compression (EHC) provides three decisive advantages over the state-of-the-art hydrogen provision from such storage system: a) The EHC device produces reduced hydrogen pressure on its suction side connected to the LOHC dehydrogenation unit thus shifting the thermodynamic equilibrium towards dehydrogenation and accelerating the hydrogen release; b) the EHC device compresses the hydrogen released from the carrier system thus producing high value compressed hydrogen; c) the EHC process is selective for proton transport and thus the process purifies hydrogen from impurities such as traces of methane. We demonstrate this combination for the production of compressed hydrogen (absolute pressure of 6 bar) from perhydro dibenzyltoluene at dehydrogenation temperatures down to 240 °C in a quality suitable for fuel cell operation e.g. in a fuel cell vehicle. The presented technology may be highly attractive for providing compressed hydrogen at future hydrogen filling stations that receive and store hydrogen in a LOHC-bound manner.