Wind power and photovoltaic energy play a significant role in sustainable energy systems. However, these two renewable energy sources do not generate electrical energy on demand and are subject to natural fluctuations. Thus, the need for compensatory measures arises. Compressed air energy storage power plants (CAES) are a possible solution to providing negative and positive control energy in the electric grid. However, in contrast to other energy storage devices such as pumped hydro energy storage or batteries, the storage medium compressed air hardly contains any energy (or more precisely: enthalpy). Yet, compressed air storage allows the operation of highly efficient gas turbines, which are not only particularly fast available but also achieve better efficiency than combined cycle power plants used today, as illustrated by the example of the modern gas and steam power plant Irsching with ηtc = 60%from 2011 compared to the 20 years older McIntosh CAES with ηtc = 82.4 %. In this thesis, the calculation methods for the thermodynamics of the CAES process are presented and validated by measured data from the operations of the CAES power plant Huntorf. Both the steady state and the dynamic (time-dependent) analyses of the process take place. The characteristic value efficiency is discussed in detail, since numerous different interpretations for CAES exist in the literature. A new calculation method for the electric energy storage efficiency is presented, and a method for the calculation of an economically equivalent electricity storage efficiency is developed. Consideration is given to the transformation of the CAES process into a hydrogen-driven and, thus, greenhouse gas-free process. Finally, a model CAES system is tested in a 100 % renewable model environment. Consequently, it can be stated that in the steady-state thermodynamic calculation in particular, the consideration of realistic isentropic efficiencies of compressors and turbines is essential to correctly estimate the characteristic values of the process. Furthermore, a steadystate view should always be accompanied by dynamic considerations, since some process characteristics are always time-dependent. The simulation shows that by mapping transient operating conditions, the overall efficiency of the system must be corrected downwards. Nevertheless, in the model environment of a 100 % renewable energy system, it has been shown that a CAES is a useful addition that can provide long-term energy storage.

This is an open access book.Energy storage systems are the key to the successful energy transition to full renewable energy supply and are more relevant today than ever before. They address numerous challenges of the energy transition at once: stabilise the electricity grids, support the shutdown of power plants, make regionally generated electricity available locally and compensate for fluctuations in renewable energy generation. For more than 15 years now, EUROSOLAR has dedicated the annual International Conference on Renewable Energy Storage (IRES) to this important topic. The conference, which has been organised in partnership with Messe Düsseldorf since 2015, addressed the current state of research and the social, political and legal framework conditions of energy storage technologies from 20 to 22 September 2022, as part of its exhibitions on decarbonised industries.In up to three parallel series of lectures, experts from science, practice, politics and society focused on the current state of knowledge about energy storage.In recent years, more than 4000 visitors attended Energy Storage Europe, the predecessor of Messe Düsseldorf’s decarbXpo and IRES, each year. In plenary sessions, topic-specific lecture series and discussion rounds, around 150 lectures were presented including a large poster exhibition.We look forward to welcoming you to the 17th IRES in 2023.

A systematic overview of the state of Compressed Air Energy Storage (CAES) technology, covering the key components and principal types of systems in the order of technical maturity: diabatic, adiabatic, and isothermal. Existing major systems and prototypes and economics are also addressed.

This book covers power system modelling in the time domain; discretisation; network formulation; network partioning; multithreading; and performance analysis. It also compares parallel simulation run times against MATLAB/Simulink.