Tapping on the Aggregate Flexibility of Heterogeneous Load Groups for EV Fast Charge Accommodation in Urban Power Distribution Networks

Abstract

Smart sustainable grids are characterized with sophisticated demand response schemes. Flexible loads are the key in the concept of demand response and, if well-planned, can save significant costs and emissions through optimal use of energy resources. On the other hand, fast charge electric vehicles, despite their appeal, represent a special type of loads demanding an immediate attendance upon admission to charging stations. This may counterbalance the efforts toward flexible load management. Moreover, there is a rising demand for fast-charge stations with a more balanced spatial distribution. In this paper, a comprehensive multi-stage residential load planning scheme is proposed incorporating the most diverse load groups in a realistic market environment. Within this procedure, a unique concept is implemented which taps into the aggregated residential load flexibility to support fast charge of electric vehicles. Through cluster-wise scheduling for different load classes, the proposed approach aggregates the flexibility of a heterogeneous population of different multi-apartment loads including air conditioning and water heating devices as well as slow-charging EVs to also plan for fast-charge-powered EVs. The results demonstrate the feasibility of the successful implementation of the proposed framework within urban neighborhoods which proves efficient in reducing fast-charge load on the grid besides financial benefits for aggregators.