Hey guys,
please correct me if I'm wrong, but I think pricing both the charge and discharge of the battery store component with the inverter's capital costs results in duplicating costs since a bi-directional inverter is considered (I checked the source of the cost assumption, Budischak 2013).
Before working with PyPSA-EUR, I have worked with the toy model WHOBS where only the charging-link of the battery store component is priced with its capital costs (cf. https://github.com/PyPSA/WHOBS/blob/master/run_single_simulation.ipynb). The proposed change in code is equivalent.
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