SAE International

Use Cases for Plug-In Vehicle Communication as a Distributed Energy Resource
 N J2836/3

Annotation

This SAE Information Report establishes use cases for a Plug-in Electric Vehicle (PEV) communicating with an Energy Management System (EMS) as a Distributed Energy Resource (DER) which must be supported by SAE J2847/3. This document also provides guidance for updates to SAE J2847/2 to allow an inverter in an EVSE to use the PEV battery when operating together as either a DER or as a power source for loads which are not connected in parallel with the utility grid. Beyond these two specific communication objectives, this document is also intended to serve as a broad guide to the topic of reverse power flow.

Purpose

Distributed Energy Resources are small, modular Distributed Generation (DG) or energy storage systems that provide electric power or energy where it is needed on the distribution grid. A PEV using a "utility-interactive inverter" can be hooked up in parallel with the primary grid power and it is defined to be a Distributed Energy Resource (DER). The use of a PEV as a DER will be called Vehicle to Grid (V2G). The term is often associated with the concept of an aggregator coordinating the power flow of many PEVs to provide frequency regulation for the bulk grid. However, V2G is not just about the bulk grid. The V2G and DER functionality can also be used by a facility energy management system to offset other facility loads during periods of peak demand. These are only two of many possible V2G applications.

Even if a PEV is not capable of reverse power flow, it can still be used as a DER device to allow for active control of charging for grid purposes. The use of a variable load for grid purposes is sometimes called Demand Dispatch or Demand Management. This can be considered a single-sided use of a DER device and is no different than a generator that can only vary power output.