This article details the ESAFORM Benchmark 2021. The deep drawing cup of a 1 mm thick, AA 6016-T4 sheet with a strong cube texture was simulated by 11 teams relying on phenomenological or crystal plasticity approaches, using commercial or self-developed Finite Element (FE) codes, with solid, continuum or classical shell elements and different contact models. The material characterization (tensile tests, biaxial tensile tests, monotonic and reverse shear tests, EBSD measurements) and the cup forming steps were performed with care (redundancy of measurements). The Benchmark organizers identified some constitutive laws but each team could perform its own identification. The methodology to reach material data is systematically described as well as the final data set. The ability of the constitutive law and of the FE model to predict Lankford and yield stress in different directions is verified. Then, the simulation results such as the earing (number and average height and amplitude), the punch force evolution and thickness in the cup wall are evaluated and analysed. The CPU time, the manpower for each step as well as the required tests versus the final prediction accuracy of more than 20 FE simulations are commented. The article aims to guide students and engineers in their choice of a constitutive law (yield locus, hardening law or plasticity approach) and data set used in the identification, without neglecting the other FE features, such as software, explicit or implicit strategy, element type and contact model.

An increasing number of energy storages will be installed in buildings with photovoltaic systems. However, batteries with only local operation tasks do not exhaust their technical potential. Using the available battery capacity in terms of power and energy to provide ancillary system services is therefore economically reasonable. Providing primary control reserve power in combination with increasing local self-sufficiency has been identified as a promising option for decentralised PV battery systems. Thereby, part of the battery capacity is used to provide grid services and the remaining part for the management and optimisation of local system operation. Provision of self-sufficiency increase is limited, when the battery's state of charge is within certain limits. In this study, it is shown that the simultaneous use of the battery to locally increase self-sufficiency reduces the need for external power sources to correct the storage level. The operational concept, the technical solutions, and a sensitivity analysis are presented. Furthermore, billing and measuring issues as well as the current regulatory framework conditions in Germany are discussed

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