  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.
