What a smart grid can do that the old power grid could not
What a smart grid can do that the old power grid could not is see itself failing in close to real time and, in many cases, fix itself before a customer calls in an outage. A grid sensor called a phasor measurement unit reads voltage and frequency about 100 times faster than older equipment, catching instability on the line instead of only recording a blackout afterward. Before a federal grid modernization program ran from 2010 to 2015, the transmission system carried fewer than 200 of these networked sensors, mostly used only for research. By the time the program closed in 2015, the country ran more than 1,700, the Department of Energy states in its own final report.
The source states fewer than 200 sensors before the program, not an exact count, and more than 1,700 nationally by 2015. The national total includes sensors outside the federally funded program that produced the middle bar, so the middle bar and the last bar do not describe the same population of devices.
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| Before the program | 200 |
| Program funded by 2015 | 1380 |
| National total by 2015 | 1700 |
In 2008, Hurricane Gustav knocked 14 transmission lines out of service and cut off part of the grid into an island around New Orleans and Baton Rouge. Entergy used its own sensors to detect the island and diagnose the instability in time to prevent a blackout across both cities, then tripled its sensor count afterward, the same report states.
How a smart grid finds and fixes an outage by itself
Fault location, isolation and service restoration technology, called FLISR, finds a broken line and fixes it without a person doing that first. Automated switches isolate the fault and reroute power to a working line in seconds, work a dispatcher used to hand to a truck. Across federally tracked projects, that cut customers affected by a typical outage by as much as 55%, and cut total minutes without power by as much as 53%, per outage event, the Department of Energy reports.
The Electric Power Board of Chattanooga, Tennessee restored power 36 hours faster after a February 2014 storm than manual switching would have allowed, and cut customers still without power from 70,000 down to 33,000, the same report states.
Ten years later, self healing grid technology at Duke Energy Florida, now covering 77% of its customers in that state, prevented more than 300,000 customer outages during hurricanes Helene and Milton in 2024, the company reports.
With storms increasing in frequency and intensity, Duke Energy Florida's Storm Protection Plan, year round infrastructure work and preparedness efforts are critical to our ability to respond quickly and safely.
Melissa Seixas, Duke Energy Florida state president. Source 2.
The two way link that makes demand response possible
None of this needed a customer to do anything, but a separate change did. A smart meter, unlike the old analog kind, can carry a signal back to a home in real time, not only send a reading out. That link lets a utility ask a customer to cut electricity use for an hour rather than build a power plant that only runs a few afternoons a year, a trade called demand response.
Figures are counted by the Energy Information Administration and reported by the Federal Energy Regulatory Commission, not derived by this article.
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| 2007 | 4.7 |
| 2012 | 29.7 |
| 2017 | 51.9 |
| 2022 | 72.3 |
The Federal Energy Regulatory Commission counts that link reaching 72.3% of every electric meter in the country in 2022, up from 4.7% in 2007. In 2023, utilities moved 33,055 megawatts of demand through it across the country wholesale electricity markets, a scale a one way meter could never support because it never sends anything back.
None of the government reports behind these numbers names a single national outage duration figure for smart grid technology as a whole. Every reliability result here is a specific utility or a specific federally tracked project, not a national average.