  In this paper, we consider the day-ahead operational planning problem of a
radial distribution network hosting Distributed Energy Resources (DERs)
including rooftop solar and storage-like loads, such as electric vehicles. We
present a novel decomposition method that is based on a centralized AC Optimal
Power Flow (AC OPF) problem interacting iteratively with self-dispatching DER
problems adapting to real and reactive power Distribution Locational Marginal
Costs. We illustrate the applicability and tractability of the proposed method
on an actual distribution feeder, while modeling the full complexity of
spatiotemporal DER capabilities and preferences, and accounting for instances
of non-exact AC OPF convex relaxations. We show that the proposed method
achieves optimal Grid-DER coordination, by successively improving feasible AC
OPF solutions, and discovers spatiotemporally varying marginal costs in
distribution networks that are key to optimal DER scheduling by modeling
losses, ampacity and voltage congestion, and, most importantly, dynamic asset
degradation.
