Abstract:

Although the area-wide introduction of electric vehicles (EVs) and electric heat pumps (HPs) would lead to the decarbonization of the energy system, existing low-voltage (LV) power grids will present new challenges. Therefore, on the basis of three contrasting load approaches applied to four separate grid regions, this study examines possible grid congestion. Within the three load approaches, temporal characteristics of various grid customer classes (EVs, HPs, households etc.) are derived from highly resolved realistic load profiles. In accordance with classic grid planning, firstly a static load approach is analyzed by applying the modeled coincidence for each consumer class individually. Secondly, this static approach is modified by including combined coincidence factors, taking temporal consumer class interactions into account. Finally, both static load approaches are compared with detailed annual time series analyses by means of load flow simulations using real-life LV grid data. The evaluation of inadmissible voltage characteristics and thermal congestions identifies future grid extension needs depending on the considered grid region. In addition, the variation of the applied load approach highlights the need to consider consumer-specific temporal behavior. In fact, the classic grid planning approach overestimates future grid extension needs by neglecting temporal interactions between traditional and future grid customers. This paper provides a combined consideration of the coincidence of EVs and HPs as well as the resulting grid effects on the LV level to combat an oversize of potential grid structures.