Distribution System Behind-the-Meter DERs: Estimation, Uncertainty Quantification, and Control

This article summarizes the three-year technical activities of the IEEE Task Force (TF) on behind-the-meter (BTM) distributed energy resources (DERs): estimation, uncertainty quantification, and control. The potential grid services from BTM DERs are discussed in detail. The paper also reviews the state-of-the-art for BTM DERs visibility, uncertainty quantification, and, optimization and control. Furthermore, different aspects of the market structures associated with BTM DERs are covered, including emerging market and business models. Finally, needs and recommendations are provided for additional areas such as system protection, computing capabilities, algorithm development, market structure design, cyberinfrastructure and security, and hardware and software developments.

I. Introduction

Distribution systems (DSs) have been witnessing increasing penetration of BTM DERs, such as solar photovoltaics (PV), battery energy storage systems (BESS), and electric vehicles (EVs), etc. Additionally, flexible buildings with controllable loads, such as electric water heaters, air conditioning systems, and other schedulable or deferrable appliances, are expected to increase substantially soon. They are usually known as BTM resources since the network operator does not individually manage their actions and control. At the same time, most power converters at the DERs interface are grid-following, which challenges this BTM-prosumer-operator coordination paradigm. Furthermore, it might be challenging for network operators to meet system voltage and frequency constraints under high penetration of uncertain renewable energy sources (RES), prosumers' actions, and a low-inertia dynamic system. Hence, smart and innovative approaches are required to ensure reliable network operation while contemplating prosumers' preferences and uncertainty. In the meanwhile, due to the lack of BTM DERs' visibility and their participation in retail compensation programs (rather than being directly involved in the regional transmission organization/independent system operator (ISO)¹

or its European counterpart - transmission system operator (TSO).

market), it is becoming challenging to harness their flexibility and potential for grid benefits fully. The uncertainties associated with BTM DERs also need to be properly quantified for decision-making.