Experts agree the electric transmission grid is evolving from massive regional systems toward transcontinental reach. As this change unfolds, the focus of operational reliability is shifting to more agile response and overall resilience.
Beyond the natural and man-made perils that have always threatened poles, wires, and transformers, digital threats from cyberterrorism now exist, along with new potential for catastrophic disruptions.
The National Academies of Science, Engineering, and Medicine in 2016 convened a panel of engineers, scientists, academicians, and technical experts to assess threats and propose strategies for improving grid resilience. The panel reviewed after-action reports from numerous incidents, examined training and drill assessments, and investigated command, control, communications, and intelligence procedures to identify strengths, weaknesses, and strategies for sustainable improvements.
Craig Miller, NRECA’s chief scientist and lead researcher, represented electric cooperatives on the panel, which published its final report in July.
RE Magazine sat down with Miller after the report was issued to get his take on its findings and recommendations.
Q: What are today’s threats to the nation’s electric power grid?
MILLER: The range of threats is enormous. Hurricanes and cyberthreats are top of mind at the moment, but there are also major storms throughout the continental United States; tornadoes; floods; vandalism; electromagnetic pulse caused by nuclear detonations; geomagnetic disturbances from solar events; and even tsunamis.
The National Academy report is an exhaustive list and characterization of all of the perils for large-scale disruption. By working through the scenarios and including them in our planning and models, we develop the beginnings of a theory and a plan to build a comprehensive approach to agility in response. This will come into play with enormous benefit when something bad happens. And something bad is going to happen.
Q: The report talks at length about “agile” grid control. Explain that and its impact on resilience.
MILLER: Beginning in the 1880s and for the century that followed, we built a grid of iron and copper. Beginning in the 1980s, we added silicon to the mix, in the form of information technology, to allow better measurement and more precise and reactive control. We’re extending the capabilities of this agile, silicon-based, information-based control. It’s cheaper, it’s cleaner, and it’s more efficient, but it’s not inherently as stable and reliable as a system with huge generators and huge transmission lines. We’ve always focused on reliability—preventing failure. Now we have the chance to think about how agile control can allow us to act more effectively when things do fail.
Q: And how do we get there?
MILLER: What we are trying to do with the National Academy study is frame the problems to challenge utilities, regulators, and everybody involved to think about how we can do better and to continue to challenge ourselves to keep improving. The National Academies challenge the federal government and other governmental organizations to do the research necessary to push the frontier. Is there research we should be doing to give the utilities more tools to address these problems?
Q: Does the current co-op operations model—Rural Utilities Service (RUS) engineering standards, mutual-aid agreements, apprentice programs and training— position us well to meet these challenges?
MILLER: If every utility did it their own way, then how does a lineman from one help out the utility next door? Co-ops tend to all do it pretty much the same way, as we follow our U.S. RUS standards. We can use the crews effectively, positioning and sharing the assets that are going to be necessary for restoration—thinking about how am I going to get to this place and what am I going to do if I have to fix that.
We’re focusing on establishing a process of continuous improvement, so that no matter how much we improve, we’re always asking, ‘What more could we do?’ It aligns culturally with our co-ops and our relentless goals of delivering safe, reliable, affordable power. This is just adding another dimension to the planning.
Q: The report offers resiliency metrics for the first time. Talk about those.
MILLER: There are five key resiliency metrics that NAS is proposing.
One, delay the onset of failure, and measure that in hours or days. People can prepare better, shut down in a safe way to mitigate system damage, and protect their property.
Two, limit the impact so that it’s not as bad as it would be if you hadn’t prepared … so you can raise the floor from losing 80 percent of power to losing 60 percent, lessening the magnitude of the impact.
Three, accelerate the start of restoration. How soon can you assess the situation and get the crews in gear? Ensuring that law enforcement knows to allow crews access to disaster sites is critical.
Four, bring the power back to the maximum level of restoration more quickly. Digital meters give us a better, more complete understanding of what’s going on. That accelerates the rate of repair because you can trace backward to determine where 500 meters share a common connection.
And then the last one is, raise the total level of restoration. Don’t leave things unrestored until the businesses fail or the people leave. That’s key to preserving a community’s economic vitality.