**Michel Zade \*, Zhengjie You, Babu Kumaran Nalini, Peter Tzscheutschler and Ulrich Wagner**

Chair of Energy Economy and Application Technology, TUM Department of Electrical and Computer Engineering, Technical University of Munich, 80333 Munich, Germany; zhengjie.you@tum.de (Z.Y.); babu.kumaran-nalini@tum.de (B.K.N.); ptzscheu@tum.de (P.T.); uwagner@tum.de (U.W.) **\*** Correspondence: michel.zade@tum.de; Tel.: +49-89-23972

Received: 9 September 2020; Accepted: 21 October 2020; Published: 27 October 2020

**Abstract:** The adoption of electric vehicles is incentivized by governments around the world to decarbonize the mobility sector. Simultaneously, the continuously increasing amount of renewable energy sources and electric devices such as heat pumps and electric vehicles leads to congested grids. To meet this challenge, several forms of flexibility markets are currently being researched. So far, no analysis has calculated the actual flexibility potential of electric vehicles with different operating strategies, electricity tariffs and charging power levels while taking into account realistic user behavior. Therefore, this paper presents a detailed case study of the flexibility potential of electric vehicles for fixed and dynamic prices, for three charging power levels in consideration of Californian and German user behavior. The model developed uses vehicle and mobility data that is publicly available from field trials in the USA and Germany, cost-optimizes the charging process of the vehicles, and then calculates the flexibility of each electric vehicle for every 15 min. The results show that positive flexibility is mostly available during either the evening or early morning hours. Negative flexibility follows the periodic vehicle availability at home if the user chooses to charge the vehicle as late as possible. Increased charging power levels lead to increased amounts of flexibility. Future research will focus on the integration of stochastic forecasts for vehicle availability and electricity tariffs.

**Keywords:** charging strategy; optimization; electricity pricing; electric vehicle; flexibility; flexibilitymarket; home energy management system
