by Jeff St. John
March 14, 2019

Utilities face a massive technical challenge in integrating distributed energy resources like rooftop solar, behind-the-meter batteries and electric vehicle chargers into their power grids — including setting the common standards for how to get there. One of the biggest stumbling blocks to early DER-grid integration pilot projects has been the lack of well-defined standards for how to manage the operating characteristics and capabilities of energy storage systems, smart inverters and other devices that aren’t part of the traditional utility toolbox. 

That’s why many of these pilot projects underway in California, Hawaii, Arizona and other solar-rich states are being matched with efforts to fine-tune and finalize the key standards involved, so that device makers can start building and testing their equipment to support them. California’s Rule 21, which required all new solar installations to support automated smart inverter functionality starting last year, and will require support of utility communications starting in August 2019, is the primary driver for companies in the market today. 

But the same set of standards — namely, IEEE 1547 for inverter-to-grid interconnection and interoperability, IEEE 2030.5 for DER-to-utility communications, and DNP3 for utility SCADA networks in the United States — are also likely to serve as the foundations for future utility efforts across the country. At least that’s the view of the utility-funded Electric Power Research Institute, which has taken the lead on much of this standards development work in the U.S.

Those include two California Energy Commission-funded projects that have yielded some useful tools for the industry this year: free open-source communications software to support the IEEE 1547-to-2030.5 interoperability to be required of all solar inverters in California starting this summer, and an “application note” that will now be mandatory for utilities using DNP3-based SCADA networks to comply with IEEE 1547. 

Both of these tools are now in use by utilities and companies in California, said Ben Ealey, information and communications technology senior projects manager at EPRI, in an interview last week. But “by making this implementation capability available, you can also meet the 1547 requirements that will be the interconnection standards for many utilities,” he noted, most likely starting with the states with mandates for more distributed energy resources, and the communications and integration needs that will come with them. 

Open-source software to get smart inverters to ‘speak’ in smart energy protocol