**6. Conclusions**

This paper describes in detail a model that calculates cost-optimal charging schedules and quantifies the flexibility of EV. A case study with more than 15,000 vehicle availabilities from Germany and the USA was conducted and the results visualized for weekdays, weekends, and an average week. Furthermore, the impact of five operating strategies and three charging power levels on the offerable flexibility were analyzed.

Based on these results, the following key findings can be drawn:


In conclusion, the model presented in Section 2 is able to quantify EV flexibility. Regulators, researchers, and system operators can use this model to investigate various influences such as tariff structures, user preferences, charging power levels etc. on the flexibility of EVs. Furthermore, the presented HEMS model can calculate the flexibility of heat pumps, combined heat and power, photovoltaic and battery systems. Once completed, this model will be a new helpful tool for tasks such as flexibility calculation, grid expansion planning, and the design and implementation of future electricity regulations.

**Supplementary Materials:** The model and the script to perform the ev case study is open-source and accessible via the following link: https://zenodo.org/badge/latestdoi/212816117.

**Author Contributions:** Conceptualization, M.Z.; data curation, M.Z.; formal analysis, M.Z. and P.T. funding acquisition, P.T. and U.W.; investigation, M.Z. and Z.Y.; methodology, M.Z. and Z.Y.; project administration, P.T. and U.W.; software, M.Z., Z.Y., and B.K.N.; supervision, P.T. and U.W.; validation, M.Z.; visualization, M.Z.; writing—original draft, M.Z. and Z.Y.; writing—review and editing, M.Z., Z.Y., B.K.N., P.T. and U.W. All authors have read and agreed to the published version of the manuscript.

**Funding:** The German Federal Ministry for Economic Affairs and Energy, Bundesministerium für Wirtschaft und Energie, funded this research under the grant number 03SIN109.

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
