The smart grid is working for ConEd’s customers

It has been six years since the state’s "smart grid" law handed Commonwealth Edison formulaic rate hikes nearly every year to finance a $2.6 billion modernization program that the utility promised would make its power grid more reliable.
ComEd has completed the reliability work now. And the results?
The news largely is good, which should make residents and business people feel better about the rate increases that funded the investment. But in a way the upgraded grid hasn’t yet been tested because the period since the 2011 Electricity Infrastructure Modernization Act (EIMA) was enacted over then-Gov. Pat Quinn’s veto has coincided with a relatively calm period of summer weather in Chicago.

Summer means many things to different people, but to everyone it means severe thunderstorms and sometimes tornadoes. Those wreak havoc on overhead power lines, creating mass outages than can take hours or sometimes days to restore.

From 2012 until 2017, the years after the law’s passage, ComEd’s northern Illinois service territory has averaged nearly 19 storms a year, with a little more than eight of those causing at least 10,000 outages lasting at least three hours, according to a report the utility submitted earlier this year to the Illinois Commerce Commission, which only recently was made public. In the five years preceding that and leading up to EIMA’s passage, there were an average of 24 storms annually, with 12 of those of the more severe variety.
The worst by far was 2011 itself, when a string of intense summer storms knocked out the lights for millions. Over the course of that whole year, 14 major storms caused a total of 2.8 million outages. ComEd struggled to respond. On average, it took the utility 366 minutes to restore power for each customer that year, which provoked widespread outrage but also helped buttress ComEd’s arguments in Springfield for rate hikes and upgrades.

In 2017, by contrast, it took 116 minutes on average to restore power. Of course, there were "only" 901,000 outages caused by 14 storms, 10 of which resulted in at least 10,000 outages lasting at least three hours.

If the record on how long it takes to restore power isn’t totally clear, that’s not the case for the number of outages on the system overall. Those undeniably are fewer–and significantly.

Each storm in the five years leading up to the law knocked out power to 88,000 customers on average. In the most recent five years, that’s down to an average of 60,000 per storm. ComEd’s moves to automatically reroute power from working equipment to customers affected by damaged equipment when it’s possible to do so clearly have had a beneficial effect.

In addition, total number of outages, whether caused by storms, squirrels or anything else, are way down per customer.
The improvement in restoration times isn’t nearly as dramatic.
In 2009, a pre-EIMA year that was a particularly light summer storm season, there were more than 650,000 total outages caused by seven serious storms. System-wide, it took ComEd 112 minutes on average to restore power. That year was more benign than 2017, but still the 116 minutes last year at least raises questions about how much restoration times would improve in a really severe season like 2011.

In an email, a ComEd spokesman expresses confidence. "The smart grid law is working, and the investments we’ve made to strengthen and modernize the electric grid are proving their value every day with record reliability for our customers, including a 46 percent decrease in the frequency and length of power outages," he said. "Today, families and businesses across northern Illinois enjoy electric service that is more reliable by every key measure, and the smart grid is well positioned to respond to storms and other weather events."
Smart grid has passed many tests, but it awaits the ultimate one.

Steve Daniels