Energy storage for mitigating grid congestion caused by electric vehicles: A techno-economic analysis using a computationally efficient graph-based methodology

This paper studies the impact of electric vehicle charging on congestion in low-voltage networks and the economic feasibility of energy storage as an alternative to conventional network upgrades. To this end, we propose a computationally efficient graph-based methodology and employ it on a GIS data set of over 6,500 low-voltage networks. We provide insights regarding the types of networks that are most congested due to electric vehicle charging, the typical location of overloaded network components, and the types of networks in which a storage-based upgrade is profitable. A main result is that the number of networks in which it is profitable to use energy storage grows exponentially as the cost of energy storage decreases, regardless of the electric vehicle penetration level and charging power. Our findings also show that using energy storage to alleviate congestion can incur substantial savings, conditioned with a cost reduction of stationary energy storage to 200 US$/kWh and below.