Sign In

Communications of the ACM

ACM News

Protecting the Smart Grid

Components of a microgrid.

Microgrids have discrete electrical boundaries and provide a single point of connection to the larger utility grid, so they can disconnect from the utility grid in response to external events such as power outages.


In 2003, a power surge led to a cascading power network failure that became the second-most widespread blackout in history, leaving more 50 million people in the eastern the U.S. and Canada in the dark, some for as long as two days.

Since then, governments and companies worldwide have been working to "smarten" their electrical generation, transmission, and distribution infrastructure, to make it more reliable, resilient, and resistant to hacking.

A U.S. Department of Energy (DoE) agency called the Advanced Research Projects Agency-Energy, ARPA-E, is now funding a project to deploy modular microgrids with local backup energy, which add resiliency to reliability by seamlessly switching power to critical infrastructure as may be required, thus avoiding power failures to strategic assets.

According to DoE, a microgrid is "a group of interconnected loads and distributed energy resources with clearly defined electrical boundaries that acts as a single controllable entity with respect to the grid (and can) connect and disconnect from the grid to enable it to operated in both grid-connected or island mode."

"Microgrids use their own machine learning and predictive maintenance features, but are not needed everywhere on the grid," according to Michael Markides, associate director of Smart Utilities Infrastructure at IHS Markit. "The biggest need for ultra-reliable and resilient microgrids with decentralized software being mission-critical applications, such as hospitals. Back-end software is the traditional centralized approach to quickly respond to an outage," explained Markides, "but today we are moving to head-end decentralized software where machine learning happens on the grid devices themselves; for instance, warning you to perform preventative maintenance before an outage."

Microgrids can also be helpful for electric vehicle (EV) recharging stations, which are already starting to weigh down the main grid, according to Adarsh Krishnan, senior analyst at market research firm ABI Research, Oyster Bay, NY, which predicts, "EVs will start to weigh down the grid more and more as they become more widely accepted." ABI forecasts 2,480 small-scale and residential EV charging station deployments globally this year will grow to 615,520 in 2021, a 240% compound annual growth rate (CAGR).

"Deployment of microgrids is a kind of a 'progressive revolution'," said Milan Rosina, senior analyst for energy conversion and emerging materials at Yole Développement (Lyon, France). "It means the global impact of microgrids will completely change the conventional energy business and energy production technology portfolio, but this will not happen immediately, nor at all locations at the same time. Microgrid deployment will feature a progressive evolution depending on the country policies, grid network development state, electricity needs, and distribution of electricity generation sources."

DoE's vision is to add a distributed smart grid operating system (grid-OS) to each energy generating component, thus enabling them to react much more quickly than assets connected via the cloud. DoE's project investigating and developing this is called the "Resilient Information Architecture Platform for a Decentralized Smart Grid," which it is supporting with $3.5 million in funding to Vanderbilt University, North Carolina State University, and the University of Washington.

Gabor Karsai, associate director of Vanderbilt's Institute for Software Integrated Systems and lead researcher on the project , "Our software is supposed to be open source like Android for smartphones, but in this case a kind of open source operating system for smart grids. In other words, it adds a kit of algorithms to control smart grids. that may have hundreds of nodes with distributed computational abilities and which also conforms to the big grid operating devices—so the grid-OS must understand all the standard big grid components,"

By casting its smarts into distributed embedded systems with a microgrid-specialized RTOS (realtime OS), damaged parts of a grid can communicate with each other to almost instantly quarantine failed areas, thus preventing cascading failures. In addition, the quarantined microgrid can be quickly fixed with local auxiliary power sources, then patched back into the main grid in seconds or minutes, rather than the hours or days it takes today.

A working prototype will be freely distributed to grid operators, and was recently shown to attendees at the recent 8th ACM/IEEE International Conference on Cyber-Physical Systems in Pittsburgh, and the 20th IEEE International Symposium on Real-Time Computing in Toronto.


The U.S. Department of Defense (DoD) in March awarded BAE Systems an $8.6-million contract to contribute to the Rapid Attack Detection, Isolation, and Characterization Systems (RADICS) program being run by the Defense Advanced Research Project Agency (DARPA) by developing technology to quickly restore power to the U.S. electric grid after a catastrophic failure caused by a cyber attack.

Said a DoD spokesperson, "DARPA has a program dedicated to speeding up the restoration of utilities in the event of a cyber attack. While Smart Grid technologies are a component of that research, the power grid in general is the focus."

Victor Firoiu, senior principal engineer and manager of Communications and Networking at BAE Systems Advanced Information Technologies, said, "The risk of a coordinated, large-scale cyber attack on the U.S. power grid has increased tremendously since Industrial Control Systems first started converging with IT networks. Today, hostile actors regularly demonstrate their advanced cyber attack skills, and malware already exists in the wild that specifically targets ICS technology. A team of well-funded, nation-backed hackers has the potential to darken electrical grids and keep them dark."

A lasting blackout is a great risk to national security, Firoiu said. "The U.S. grid is large and complex, and starting it back up quickly takes a lot of coordination, something made much more difficult when the power is out and other means of communications have also been crippled by simultaneous cyber attacks. DARPA recognizes the risks that the U.S. power grid faces and is actively looking to address via its RADICS program. BAE Systems is working closely with them on two critical parts of the program. We're developing a way to isolate the network from non-cooperative organizations to hinder ongoing attacks, and we're developing technology for creating an infrastructure-less, resilient Secure Emergency Network, which will enable grid operators to conduct the necessary communication and coordination to restore power."

Threats to the grid are also being minimized at the National Association of Regulatory Utility Commissioners (NARUC), a non-profit that represents state public service commissions regulating utilities, according to Miles Keogh, director of the organization's research lab, where he runs workshops, does training, and provides technical assistance as a liaison between members of NARUC and the U.S. Department of Energy, the U.S. Environmental Protection Agency, and the U.S. Department of Homeland Security.

"The only confirmed hack that affected the power grid itself was in the Ukraine," said Keogh. "About 18 months ago, NARUC blew the whistle on our grid's vulnerability to 'ransomware' attacks, encouraging U.S. utilities to strengthen their vulnerabilities. Now, NARUC can't take the credit, but so far, our utilities have not been beaten by the most recent ransomware attacks."

R. Colin Johnson is a Kyoto Prize Fellow who ​​has worked as a technology journalist ​for two decades.


No entries found

Sign In for Full Access
» Forgot Password? » Create an ACM Web Account