Impacts of Community and Distributed Energy Storage Systems on Unbalanced Low Voltage Networks

TL;DR

This paper evaluates how community and distributed energy storage systems can improve unbalanced low voltage networks by reducing losses, increasing capacity, and balancing the network, using a mixed integer quadratic programming model on a real UK grid.

Contribution

It introduces a MIQP model for optimal ESS sizing and placement in unbalanced LV networks, comparing community and distributed configurations with real-world data.

Findings

DESSs slightly outperform CESS in network performance.

Both ESS scenarios significantly reduce power losses.

DESS benefits increase with larger aggregated size.

Abstract

Energy storage systems (EES) are expected to be an indispensable resource for mitigating the effects on networks of high penetrations of distributed generation in the near future. This paper analyzes the benefits of EES in unbalanced low voltage (LV) networks regarding three aspects, namely, power losses, the hosting capacity and network unbalance. For doing so, a mixed integer quadratic programmming model (MIQP) is developed to minimize annual energy losses and determine the sizing and placement of ESS, while satisfying voltage constraints. A real unbalanced LV UK grid is adopted to examine the effects of ESS under two scenarios: the installation of one community ESS (CESS) and multiple distributed ESSs (DESSs). The results illustrate that both scenarios present high performance in accomplishing the above tasks, while DESSs, with the same aggregated size, are slightly better. This margin is expected to be amplified as the aggregated size of DESSs increases.