IEEE Standard

One of the most notable national efforts in the development of interconnection standards comes from the Institute of Electrical and Electronics Engineers (IEEE). In 1999, under the organization's Standards Coordinating Committee 21 (SCC21), the IEEE formed working group P1547 to establish common practices for the grid interconnection of DER. The Project Authorization Request (PAR) submitted for approval by IEEE provided the following description for this new standard:

Title: "Standard for Interconnecting Distributed Resources with Electric Power Systems"

Scope: "This standard establishes criteria and requirements for interconnection of distributed resources with electric power systems."

Purpose: "This document provides a uniform standard for interconnection of distributed resources with electric power systems. It provides requirements relevant to the performance, operation, testing, safety considerations, and maintenance of the interconnection."

The IEEE P1547 working group is supported by of hundreds of representatives from industry trade organizations, electric utilities, DER equipment manufacturers, and national laboratories. The effort is receiving funding from the U.S. Department of Energy (DOE) to complete the interconnection standard on an accelerated schedule of approximately two to three years.

The IEEE interconnection standard will address the interface between a DER device and a utility system (or alternative power system), including protection requirements at the interface. The standard will be written in a manner broad enough to cover a variety of situations in the installation and interconnection of a DER device to a power system. The power system could be the utility-owned electric grid or a separate delivery system, such as might exist in a large industrial facility or military base.

The standard will address the interconnection of all major types of DER technologies. It will not provide requirements for power system changes that may be necessary elsewhere (away from the point of the DER interface), as a consequence of interconnection of a DER device. Such system-level changes will vary from case to case and will be determined by the current design of the power system, the type and amount of DER to be installed and interconnected, and the functions that the DER is to provide. Hence, system-level changes are not addressable by standardization and will require an engineering analysis on a case-by-case basis. A brief section is planned for inclusion in the interconnection standard explaining the need for such analysis.

In summary, the IEEE standard for interconnection of DER devices will address electrical interconnection at the point of interface, or point of common coupling. However, it will not cover broader impacts of DER on the power system.