IEEE 1547-2018, IEEE Standard for Interconnection and Interoperability of Distributed Energy Resources with Associated Electric Power Systems Interfaces, is the standard for interconnecting all technologies of DER (Distributed Energy Resources), including solar PV and battery storage to distribution systems.  The standard is critical to the industry, since it contains requirements to increase the compatibility of increasing numbers of inverter-based resources (IBR) connecting to the distribution systems, including requirements for ride-through/support for bulk power frequency and voltage events, capability for all DER to have voltage control capabilities, requirements for DER interoperability and communications interfaces, and more.

IEEE 1547-2018 was approved and published by IEEE in 2018, but inclusion of the standard into state interconnection procedures and the commercial availability of smart inverters meeting the standard is still a work-in-progress.  The primary cause for the delay was the approval of IEEE 1547.1-2020, which contains the testing standards for meeting the requirements in the parent standard IEEE 1547-2018, and the subsequent approval and issues resolution of UL 1741 SB, which contains the actual test procedures by which the inverters are certified when the inverters are tested by NRTLs (Nationally Recognized Testing Laboratory).

In an analysis performed by the non-profit IREC (Interstate Renewable Energy Council) as described on their website July 20, 2022, it reported that most smart inverter manufacturers will have UL 1741 SB-certified products initially available throughout 2023.  This will clear the way for more states and jurisdictions to mandate the use of UL 1741 SB-certified inverters and include IEEE 1547-2018 in their interconnection procedures.

To prepare for the industry’s continuing need to understand IEEE 1547-2018 requirements for solar PV projects, Electric Distribution Academy and HeatSpring will launch a new course in January 2023 called “Understanding IEEE 1547-2018 for DER Interconnections to Distribution Systems”.  More details will be made available through, and you can sign up for HeatSpring Magazine, which has several updates weekly on the Clean Energy Industry.