Proceedings of the International Renewable Energy Storage Conference 2021 (IRES 2021)
Kathrin Kefer, Patrick Kefer, Markus Stöger, Bernd Hofer, Michael Affenzeller, Stephan Winkler
Due to the increasing usage of renewable energy sources like photovoltaic (PV) systems in the private sector and their fluctuations in production, energy management systems (EMS) are becoming more and more important. As such system use the produced energy as efficiently as possible, they also have an...
Power-to-Process-Heat in Industrial Combined Heat and Power Plants – Integration of a Large-Scale Thermochemical Energy Storage
Gesa Backofen, Manuel Würth, Annelies Vandersickel, Stephan Gleis, Hartmut Spliethoff
With an increasing share of electricity from renewable energy sources in the German energy market, storage systems are needed to close the gap between production and demand. The thermochemical storage system based on the reversible reaction of CaO and Ca(OH)2 is one of the most promising approaches for...
Monika Graff, Olaf Wollersheim, Johanna May
Several attempts have been made to define and measure performance parameters of photovoltaic home storage systems. Ideally, performance parameters are accepted by the scientific community as well as by manufacturers, test laboratories and customers. The German industry association for energy storage...
Xylitol Used as Phase Change Material: Nucleation Mechanisms of the Supercooling Rupture By Stirring
L. Piquard, E. Gagnière, G. Largiller, D. Mangin, F. Bentivoglio
Owing to its high energy density, Xylitol is a very promising Phase Change Material (PCM) for low temperature applications (< 100°C). However, it presents a high and persistent supercooling that inhibits the latent heat restitution during thermal discharges. Bubbling in the supercooled PCM is known...
Fabian Ochs, Abdulrahman Dahash, Alice Tosatto, Michael Reisenbichler, Keith O’Donovan, Geoffroy Gauthier, Christian Kok Skov, Thomas Schmidt
Large-scale thermal energy storages (TES) are advantageous to bridge the seasonal gap between heat demand and availability of renewables. However, the high investment costs associated with large-scale TES is still seen as a major barrier. Among others, challenges are space availability and the presence...
The Challenge of Planning and Constructing Large-Scale Hot Water TES for District Heating System: A Techno-Economic Analysis
Alice Tosatto, Fabian Ochs, Abdulrahman Dahash, Christoph Muser
In an international context (e.g. Germany, Denmark), the integration of long-term thermal energy storage (TES) into block heating systems already exists. Yet, the so-called pit TES cannot be easily applied to central European district heating (DH) systems because of the varying heat demand, temperature...
Insulating Piles for the Cost-effective Construction of Very Large-scale High Temperature Thermal Energy Storage
Alice Tosatto, Fabian Ochs, Abdulrahman Dahash, Christoph Muser, Felix Kutscha-Lissberg, Peter Kremnitzer
Large-scale thermal energy storage (TES) represents a key component in renewables-based district heating (DH) networks. However, the storage of water at high temperature (< 100 °C) for long periods can lead to a significant amount of thermal losses to the surroundings and to unwanted increase of groundwater...
Abdulrahman Dahash, Fabian Ochs, Alice Tosatto
Large-scale seasonal thermal energy storage (STES) substantially facilitates a full exploitation of the local renewable energy sources (e.g. geothermal, solar, waste heat) potential in renewables-based district heating systems in order to mitigate CO2 emissions and the climate change. Large-scale seasonal...
Yousif Muhammad, Kai Knobloch, Henrik Lund Frandsen, Kurt Engelbrecht
High temperature thermal energy storage units can provide the flexibility required, by storing the excess energy in the form of heat and suppling it back either into the electric grid or as heat to any energy intense industrial process. DTU Energy has constructed a vertical flow high temperature thermal...
Philipp Schreiber, Mathias Hofmann, Marco Wieland
One of the main concerns in extending variable renewable energy (VRE) is the electric grid stability due to the sources’ volatility. Germany is introducing a new auction mechanism within the German Renewable Energy Sources Act called “Innovationsausschreibung” (innovation tender) to grid- and system-supporting...
Gayaneh Issayan, Bernhard Zettl
The ongoing process of thermochemical material development for improved thermal storage applications relies on flexible material characterization in terms of storage capacity, mechanical stability and cycling durability. This work purposes a time-efficient thermogravimetric method and the corresponding...
An Open Circuit Voltage and Overpotential Model for an All Vanadium Redox Flow Battery Derived from Several Years of Operating Data
One essential part in the simulation of electrochemical storage systems like redox flow batteries is the voltage on cell level. In this study, a model is derived for the open circuit voltage and the overpotentials of an all Vanadium system, based on the operation data of three commercial batteries over...
Experimental Investigation of the Cycle Stability of different Iron Oxide Composites for a Redox Hydrogen Storage Process
Lea Huber, Bernd Gamisch, Belal Dawoud
A promising process to store hydrogen is the thermochemical storage based on the repeated reduction and oxidation (redox) of iron oxide or iron. This storage process is an intermittent, two-phase reaction, which takes place under atmospheric pressure in a hydrogen atmosphere during reduction (charging)...
Karin Rindt, Lukáš Pilař, Frantisek Hrdlička
Renewable Energy Sources naturally deliver energy intermittently, causing fluctuations in energy supply. The energy is therefore also not provided corresponding to the actual need, but according to the availability. Hence, the demand for energy storage is rising with the increasing utilization of renewable...
Energy Services and their Compatibility with Increasing Self-consumption as Primary Service with a Focus on Germany
Jan Wiesenthal, Frieder Schnabel
Battery energy storages play an important role in the energy transition toward an energy system based on renewable resources. Today, batteries on a household and community level in Germany are primarily used to increase consumption of self-produced electricity. However, batteries used solely for increasing...
Energy Rebels? How Households’ Preferences for Decentralized Hydrogen Systems Misalign with Energy System Requirements
Anna-Lena Klingler, Nektaria Tagalidou, Nora Fronemann
Using findings from a survey of 350 participants, we answer the question to what extent the trends towards more digitalisation and environmental awareness could create a market for decentralized hydrogen applications. The results show that while energy experts are sceptical towards the benefit of decentralized...
Giving Anergy a Value by the Application of an Anergy-exergy Cost Ratio in Thermo-economic Analysis of Systems that Make Thermal Energy Available
Lutz Meyer, Ingo Stadler
Techno-economic analysis that allocate costs to the energy flows of energy systems are helpful to understand the formation of costs within processes and to increase the cost efficiency. For the economic evaluation, the usefulness or quality of the energy is of great importance. In exergy-based methods,...
Development of a Test Method to Evaluate Lithium-Ion Batteries for Second Life in Renewable Energy Applications
Mussab Najeeb, Ulf Schwalbe
Lithium-ion batteries can still be used in many applications after removal from their first use in electric vehicles, e.g. as a storage media in photovoltaic systems and for grid support. Therefore, there is a great need to develop reliable methodologies and tools to characterize the expected performance...