Netherlands

A review of more than 60 studies (plus m4ore than 65 studies on P2G) on power and energy models based on simulation and optimization was done. Based on these for power systems with up to 95% renewables the electricity storage size is found to be below 1.5% of the annual demand (in energy terms). While for 100% renewables energy systems (power heat mobility) it can remain below 6% of the annual energy demand. Combination of sectors and diverting the electricity to another sector can play a large role in reducing the storage size. From the potential alternatives to satisfy this demand pumped hydro storage (PHS) global potential is not enough and new technologies with a higher energy density are needed. Hydrogen with more than 250 times the energy density of PHS is a potential option to satisfy the storage need. However changes needed in infrastructure to deal with high hydrogen content and the suitability of salt caverns for its storage can pose limitations for this technology. Power to Gas (P2G) arises as possible alternative overcoming both the facilities and the energy density issues. The global storage requirement would represent only 2% of the global annual natural gas production or 10% of the gas storage facilities (in energy equivalent). The more options considered to deal with intermittent sources the lower the storage requirement will be. Therefore future studies aiming to quantify storage needs should focus on the entire energy system including technology vectors (e.g. Power to Heat Liquid Gas Chemicals) to avoid overestimating the amount of storage needed.

In order to maximise European national and regional research and innovation potential the European Union is investing in these fields through different funding mechanisms such as the ESIF or H2020 programme. This investment plan is part of the European 2020 strategy where the concept of Smart Specialisation is also included.<br/>Smart Specialisation is an innovation policy concept designed to promote the efficient and effective use of public investment in regional innovation in order to achieve economic growth. The Smart Specialisation Platform was created to support this concept by assisting regions and Member States in developing implementing and reviewing their research and innovation Smart Specialisation strategies.<br/>The Smart Specialisation Platform comprises several thematic platforms. The thematic Smart Specialisation Platform on energy (S3PEnergy) is a joint initiative of three European Commission services: DG REGIO DG ENER and the Joint Research Centre (JRC). The main objective of the S3PEnergy is to support the optimal and effective uptake of the Cohesion Policy funds for energy and to better align energy innovation activities at national local and regional level through the identification of the technologies and innovative solutions that support in the most cost-effective way the EU energy policy priorities.<br/>In the particular case of hydrogen technologies the activities of the platform are mainly focused on supporting the new Fuel Cells and Hydrogen Joint Undertaking (FCH JU) initiative involving regions and cities. To date more than 80 European cities and regions have committed to participate in this initiative through the signature of a Memorandum of Understanding and more participants are expected to join. S3PEnergy is helping in the identification of potential combination of H2020 funding (provided through FCH JU) and ESIF.<br/>To identify potential synergies among these two funding sources a mapping of the different ESIF opportunities has been performed. In order to map these opportunities Operational Programmes (OPs) and research and innovation strategies for Smart Specialisation (RIS3) of the different European regions and Member States were analysed. The results of this mapping and analysis are presented in this paper."

The influence of the initial tank temperature on the evolution of the internal gas temperature during the refuelling of on-board hydrogen tanks is investigated in this paper. Two different types of tanks four different fuel delivery temperatures (from ambient temperature refuelling to a pre-cooled hydrogen at −40 °C) several filling rates and initial pressures are considered. It has been found that the final gas temperature increases linearly with the increase of the initial tank temperature while the temperature increase (ΔT) and the final state of charge (SOC) decrease linearly with increasing the initial temperature. This dependency has been found to be larger on type III than on type IV tank and larger the larger the initial pressure. Additionally CFD simulations are performed to better understand the role of the relevant phenomena on the gas temperature histories e.g. gas compression gas mixing and heat transfer. By comparing the results of calculations with adiabatic and diathermal tank walls the effect of the initial gas temperature has been separated from the effect of the initial wall temperature on the process.

The deployment of diverse energy storage technologies with the combination of daily weekly and seasonal storage dynamics allows for the reduction of carbon dioxide (CO₂) emissions per unit energy provided. In particular the production storage and re-utilization of hydrogen starting from renewable energy has proven to be one of the most promising solutions for offsetting seasonal mismatch between energy generation and consumption. A realistic possibility for large-scale hydrogen storage suitable for long-term storage dynamics is presented by salt caverns. In this contribution we provide a framework for modelling underground hydrogen storage with a focus on salt caverns and we evaluate its potential for reducing the CO₂ emissions within an integrated energy systems context. To this end we develop a first-principle model which accounts for the transport phenomena within the rock and describes the dynamics of the stored energy when injecting and withdrawing hydrogen. Then we derive a linear reduced order model that can be used for mixed-integer linear program optimization while retaining an accurate description of the storage dynamics under a variety of operating conditions. Using this new framework we determine the minimum-emissions design and operation of a multi-energy system with H₂ storage. Ultimately we assess the potential of hydrogen storage for reducing CO₂ emissions when different capacities for renewable energy production and energy storage are available mapping emissions regions on a plane defined by storage capacity and renewable generation. We extend the analysis for solar- and wind-based energy generation and for different energy demands representing typical profiles of electrical and thermal demands and different CO₂ emissions associated with the electric grid.

Certification of hydrogen sensors to meet standards often prescribes using large-volume test chambers. However feedback from stakeholders such as sensor manufacturers and end-users indicates that chamber test methods are often viewed as too slow and expensive for routine assessment. Flow-through test methods are potentially an efficient and cost-effective alternative for sensor performance assessment. A large number of sensors can be simultaneously tested in series or in parallel with an appropriate flow-through test fixture. The recent development of sensors with response times of less than 1s mandates improvements in equipment and methodology to properly capture the performance of this new generation of fast sensors; flow methods are a viable approach for accurate response and recovery time determinations but there are potential drawbacks. According to ISO 26142 flow-through test methods may not properly simulate ambient applications. In chamber test methods gas transport to the sensor is dominated by diffusion which is viewed by some users as mimicking deployment in rooms and other confined spaces. Conversely in flow-through methods forced flow transports the gas to the sensing element. The advective flow dynamics may induce changes in the sensor behaviour relative to the quasi-quiescent condition that may prevail in chamber test methods. The aim of the current activity in the JRC and NREL sensor laboratories is to develop a validated flow-through apparatus and methods for hydrogen sensor performance testing. In addition to minimizing the impact on sensor behaviour induced by differences in flow dynamics challenges associated with flow-through methods include the ability to control environmental parameters (humidity pressure and temperature) during the test and changes in the test gas composition induced by chemical reactions with upstream sensors. Guidelines on flow-through test apparatus design and protocols for the evaluation of hydrogen sensor performance have been developed. Various commercial sensor platforms (e.g. thermal conductivity catalytic and metal semiconductor) were used to demonstrate the advantages and issues with the flow-through methodology.

Several approaches have been used in the past to model the source of a high pressure under-expanded jet such as the computationally expensive resolution of the jet shock structure and the simpler pseudo-source or notional nozzle approaches. In each approach assumptions are made introducing inaccuracies in the CFD calculations. This work assesses the effect of different source modelling approaches on the accuracy of CFD calculations by comparing simulation results to experimental data of the axial distribution of the flow velocity and H2 concentration.

The successful Computational Fluid Dynamics (CFD) benchmarking activity originally started within the EC-funded Network of Excellence HySafe (2004-2009) continues within the research topics of the recently established “International Association of Hydrogen Safety” (IA-HySafe). The present contribution reports the results of the standard benchmark problem SBEP-V21. Focus is given to hydrogen dispersion and accumulation within a non-ventilated ambient pressure garage both during the release and post-release periods but for very low release rates as compared to earlier work (SBEP-V3). The current experiments were performed by CEA at the GARAGE facility under highly controlled conditions. Helium was vertically released from the centre of the 5.76 m (length) x 2.96 m (width) x 2.42 m (height) facility 22 cm from the floor from a 29.7 mm diameter opening at a volumetric rate of 18 L/min (0.027 g/s equivalent hydrogen release rate compared to 1 g/s for SBEP-V3) and for a period of 3740 seconds. Helium concentrations were measured with 57 catharometric sensors at various locations for a period up to 1.1 days. The simulations were performed using a variety of CFD codes and turbulence models. The paper compares the results predicted by the participating partners and attempts to identify the reasons for any observed disagreements.

Fuel cell electric vehicles convert chemical energy of hydrogen into electricity to power their motor. Since cars are used for transport only during a small part of the time energy stored in the on-board hydrogen tanks of fuel cell vehicles can be used to provide power when cars are parked. In this paper we present a community microgrid with photovoltaic systems wind turbines and fuel cell electric vehicles that are used to provide vehicle-to-grid power when renewable power generation is scarce. Excess renewable power generation is used to produce hydrogen which is stored in a refilling station. A central control system is designed to operate the system in such a way that the operational costs are minimized. To this end a hybrid model for the system is derived in which both the characteristics of the fuel cell vehicles and their traveling schedules are considered. The operational costs of the system are formulated considering the presence of uncertainty in the prediction of the load and renewable energy generation. A robust minmax model predictive control scheme is developed and finally a case study illustrates the performance of the designed system.

The development of the temperature field in hydrogen tanks during the filling process has been investigated with Computational Fluid Dynamics (CFD). Measurements from experiments undertaken at the JRC GasTef facility have been used to develop and validate the CFD modelling strategy; by means of the CFD calculations the effect of the injector direction on the temperature distribution has been analysed. It has been found that the dynamics of the temperature field including the development of potentially detrimental phenomena like thermal stratification and temperature inhomogeneity e.g. hot spots can be significantly affected by the injector orientation.

To develop safety strategies for the use of hydrogen indoors the HyIndoor project is studying the behaviour of a hydrogen release deflagration or non-premixed flame in an enclosed space such as a fuel cell or its cabinet a room or a warehouse. The paper proposes a safety approach based on safety objectives that can be used to take various scenarios of hydrogen leaks into account for the safe design of Hydrogen and Fuel Cell (HFC) early market applications. Knowledge gaps on current engineering models and unknown influence of specific parameters were identified and prioritized thereby re-focusing the objectives of the project test campaign and numerical simulations. This approach will enable the improvement of the specification of openings and use of hydrogen sensors for enclosed spaces. The results will be disseminated to all stakeholders including hydrogen industry and RCS bodies.