  In this paper, the extent to which the integration of rooftop photovoltaic
(PV) power with a community energy storage (CES) system can reduce energy cost
and distribution network (DN) loss is explored. To this end, three energy
trading systems (ETSs) are compared; first, an ETS where PV users exchange
energy with the CES system in addition to the grid, second, an ETS where PV
users merely exchange energy with the CES system, and third, an ETS where PV
users only exchange energy with the grid. A multi-objective optimization
framework, combined with a linear distribution network power flow model, is
developed to study the trade-off between the energy cost and network power loss
reductions while satisfying the DN voltage and current flow limits.
Simulations, with real energy demand and PV power data, highlight that enabling
the energy exchange between the users and the CES system can give a better
trade-off between the DN power loss and energy cost reductions. Further,
simulations demonstrate that all three ETSs deliver nearly 85% DN energy loss
reduction with significantly increased revenues compared to an ETS without a
CES system.
