The Open Standard for Grid-Edge Controls Is Emerging

Siemens, Accenture, NREL looking to evolve distributed generation integration from “plug-and-pray” to “plug-and-play.”

At this week’s Grid Edge Live conference, we’ve heard a lot of discussion about the need for technology that can standardize how distributed solar, smart inverters, energy storage, microgrids and other edge-of-network energy systems interact with the grid at large. Think of concepts like an operating system for the distributed energy landscape, or an internet of things for the grid edge, as we’ve seen it framed in two panel sessions so far.

Of course, there’s a lot of complicated and arduous technology development work going on behind these kinds of broad concepts. One such project we’ve been tracking involves an effort, instigated by utility Duke Energy, to allow distributed energy assets to communicate with intelligent grid devices in the field, in real time, via a standard dubbed the Open Field Message Bus, or OpenFMB.

Over the past three years, Duke has grown the list of companies participating in what it’s dubbed the “Coalition of the Willing” from six to 25, including some of the world’s biggest grid vendors. It’s also brought more utilities on board, gotten OpenFMB into the list of standards being developed by the Smart Grid Interoperability Panel, and tapped the Industrial Internet Consortium, an even larger group of companies working on IOT standards, to play a role.

Last week, coalition member Omnetric Group, a joint venture of Accenture and Siemens, started a project that will test this IT architecture with another key partner -- the Energy Department’s National Renewable Energy Laboratory (NREL). It’s one of several new NREL partners trying to find ways to integrate more renewable energy into the grid, but with a focus on open tech standards that could be picked up by the industry at large.

This isn’t just an experiment, Omnetric Group CEO Wade Malcolm said in an interview last week. “What we’re building for NREL, we’ve made a commitment that we’ll make it available in the marketplace,” he said. “We will be in the market in 18 months supporting this, and supporting the integration of existing devices.”

That’s a fairly aggressive timeline for getting a new technology in play in the utility world. Today, most of the equipment being built for the grid by companies like Siemens, General Electric, ABB, S&C Electric, Schneider Electric and Toshiba is built on proprietary technologies, developed to work smoothly with their own equipment -- but not necessarily to easily work with others.

That makes for expensive and complicated integration for projects trying to solve the kinds of problems that are emerging on the edge of the distributed-energy-equipped grid. One typical utility-facing example is getting rooftop solar-connected smart inverters, on-site batteries, and grid-side voltage regulators to respond in unison to a drop in solar output when clouds pass overhead.

This kind of disruption tends to happen too quickly to react to, if each device has to send its data back to a utility control center for processing and control instructions. But a field message bus -- a piece of hardware with computing power out on the distribution grid with communications links to all of these devices -- can collect and analyze data, make decisions, and send commands quickly enough to solve the problem. 

Using open standards for this kind of work is important, Malcolm said, in order to reduce the time and cost required by the utilities, control system vendors, microgrid developers, or other potentially interested parties to write the software that tells all these interlocking devices what to do.

“We’re making every effort to prove with this NREL project that we can get the grid to perform better, and thus integrate higher levels of renewables into the grid -- and we should be able to do it with interoperable standards,” he said.

One of the earliest venues for testing this interoperability may come from Siemens, in the form of its newly launched microgrid control system. “At the NREL project, we’re leveraging that microgrid management software and augmenting it with the Duke architecture, the OpenFMB,” he said.

The idea is to see how Siemens’ platform can use these standards to run a microgrid in three different ways, he said. One is as a self-contained unit, another is as a “hybrid” version combining on-site and utility controls, and third is as a “totally distributed” capability, as part of Siemens’ advanced distribution management system (ADMS).

Lots of different microgrid controllers manage these tasks in different ways, but they “tend to be very proprietary, and only work with specific sets of equipment,” he said. “We’re doing this to make things interoperable. I can take a battery system from Vendor A, and integrate it with a solar array from Vendor B, and use OpenFMB to put these things together.”

Byron Washom, the UC San Diego strategic energy initiatives director who’s led the development of the university’s cutting-edge microgrid, noted in a Tuesday Grid Edge Live panel that this lack of standards is a serious problem for scaling up microgrids beyond their currently limited scale.

“If this industry is going to advance at the speed of the market pull, then these standards have to emerge,” he said. “Eventually, we’ll get to plug-and-play.” In a world without these kinds of standards in place, however, “we have a saying on our campus -- it’s ‘plug-and-pray.’” 

Standards-based technology can also open up a world of innovation, in terms of how to put distributed energy asset integrations to uses not even thought of when they were first put together, Stuart Laval, Duke Energy’s technology development manager, said during a Wednesday Grid Edge Live panel.

“People are starting to see the value of sharing this data,” he said, citing the well-known axiom from Ethernet co-creator Robert Metcalfe, known as Metcalfe’s law, that the value of a communications network grows at a rate proportional to the square of the number of users or devices it connects. The more that standards percolate into the utility world, the more these systems can open themselves up to the potential for this kind of growth in value -- which is why “utilities will continue to invest in standards,” he said.