Hydrogen

Summary

Novel technologies for sustainable hydrogen-based energy systems

We develop and optimize components and systems for the production, storage, and distribution, as well as for the use of hydrogen as an energy carrier or industrial/chemical feedstock for various applications. From electrolysis to compressed gas systems, cryogenic tank systems, and filling stations, to fuel cell systems (including hydrogen conditioning in vehicles and aircraft), we consider numerous systems along the value chain.

Storage and Distribution of H2

Refueling station concepts and refueling processes

We compare, evaluate, and optimize system topologies as well as operating strategies of hydrogen refueling station systems using model-based design and performance analysis. For this, we leverage component models from TIL Suite and the hydrogen-specific Add-On HydrogenEnergySystems. Some examples of the analyses we perform for our customers are:

  • Model-based prediction of subsystems, e.g. H2 precooling (temperature and cooling capacity) or storage capacities

  • Analysis of unloading and loading processes of tube trailers and vehicle storage systems

  • Analysis of refueling station concepts, e.g. cascade vs. booster refueling

  • Analysis of operating strategies for refueling of refueling station storage systems

  • Analysis of the power and energy demand of filling stations

  • Analysis of the thermal behavior of filling stations and vehicle storage tanks during refueling processes

In the heavy-duty vehicle sector, there are currently no uniform standards for refueling vehicle storage systems. To determine custom refueling protocols (following SAE J2601 or individual customer requirements), we use the model-based and automated capabilities of our software MoBA Automation.

Figure 1: Flow diagram of a dynamic simulation model of a typical hydrogen refueling station with compressed gas storage, cascading dispensing operation, and a vehicle being refueled

Production and Application of H2

Fuel cell systems

On behalf of our customers we investigate PEMFC and SOFC systems in detail, drawing on our many years of experience from various customer and research projects. 

 

With our system models we can represent the following subsystems:

  • Different types of FC stacks

  • Peripheral components of the anode and cathode paths

  • Cooling circuits

  • Interactions between these subsystems

Figure 2: Flow diagram of a dynamic simulation model of a typical mobile FC system.

Detailed material data models, which are part of our material data library TILMedia, are used to describe gas mixtures with a dynamic mixing ratio. This is the basis for the analysis of fundamental physical effects and dependencies at the component and system level. For example, we consider the following specific aspects:

Fuel cell stacks

  • Concentration profiles along the gas channels

  • Resulting electrical performance

  • Critical internal conditions, e.g. membrane moisture or electrode potentials

PEMFC systems

  • Water balance and conditioning of supply gases for stable and efficient operation

  • Cathode-side membrane humidification

  • Anode-side purge and recirculation strategies for control of hydrogen concentration

SOFC systems using carbon-based fuels

  • System efficiency as a function of fuel composition (H2, CO, CH4)

  • Appropriate anode-side recirculation to optimize oxygen to carbon ratio

  • Identification of critical compositions and temperature levels with respect to potential soot formation

Figure 3: Illustration of exemplary results from a global optimization study to determine the Pareto optimum system efficiency. The optimization parameters are the operating pressure of the stack and the H2 stoichiometry (recirculation). a) Achieved efficiency in the allowable parameter range. The maximum achievable stoichiometry is limited by the maximum speed of the recirculation blower (bottom right). High system efficiencies (red) are achieved in principle at lower pressure and lower stoichiometry. b) Efficiency above the resulting mean membrane moisture. The Pareto optimum found (black circle) lies exactly on the minimum allowed mean membrane moisture, which is an essential constraint of the optimization problem

Power-to-X processes

Power-to-X (PtX) processes can be used to produce synthetic feedstock, fuels, and combustibles from electrical energy. We offer support to customers using such processes with our simulation models. For example, in the context of a high-temperature co-electrolysis in a SOEC/rSOC with subsequent methanation, we use simulation analyses to determine the appropriate composition of the synthesis gas (power-to-syngas) as well as the potential for utilizing heat sources and sinks. For this purpose, we use the description of chemical reactions, such as water vapor reformation or the (reverse) water gas shift reaction, to create simplified models for ideal reactors.

H2 in Aviation

H2 storage and conditioning, fuel cell systems, and thermal management 

Hydrogen offers promising prospects as a fuel for future low-emission aircraft, both in fuel cells and combusted in classical gas turbines.

 

With our expertise in modeling and simulation of hydrogen systems in aviation, we support our customers in a wide range of problems:

  • Storage of liquid hydrogen

  • Thermal conditioning of hydrogen

  • Thermal management of fuel cell systems

  • Operation and control strategies of fuel cell systems

Contact

Your contact partner

If you have any questions regarding the storage of H2, please contact:

M.Sc. Lisa Busche

+49/531/390 76 - 270

Contact

Your contact partner

If you have any questions regarding production and application of H2, please contact:

Dr. rer. nat. André Thüring

+49/531/390 76 - 235