As utilities deploy smart grid technology, more are also investing in telecom infrastructure to transmit data.
Sensors, smart meters, and other digital devices have the potential to transform the nation’s electric grid — from outage-detecting utility poles to household appliances programmed to run only when wind power is plentiful.
All the promise of smart grid technology, though, depends on data flowing back and forth between various equipment — and that requires bandwidth.
As utilities deploy more smart grid technology, some are increasingly wary of relying too much on public carrier networks to transmit data. ComEd and Ameren in Illinois are among the utilities investing in their own telecom infrastructure to expand, replace or enhance existing networks.
While private networks can be more reliable than public ones like Verizon or AT&T, the cost of building and maintaining them can cost millions of dollars — money that some critics say could be better spent on utilities’ core business of delivering electricity to customers.
Prior to the emergence of smart grid technology, utilities’ telecom needs involved communication among a handful of centralized points on the grid, such as power plants and substations. While they invested in some of their own infrastructure, utilities leased much of their communication capacity, including copper-based circuits and other services, from phone companies, said Tim Godfrey, telecommunications program manager at the Electric Power Research Institute.
As the grid has become more digitized and distributed, utilities’ needs have become far more complex. Meanwhile, the telecom industry has also undergone a huge transformation in recent decades. “The whole telecom industry has completely changed, and that’s had a huge impact on how utilities handle their telecom,” Godfrey said.
New generations of wireless communication and cellular service have led to a divergence of priorities. Utilities, mandated to spend efficiently, usually need equipment that can last at least a decade. Their service needs to reach all regions of the country, including rural areas. Public carriers, on the other hand, frequently update technology to meet customer demand, and their networks prioritize areas with high customer density over rural areas.
Telecom companies are also regulated less than utilities, so they don’t have the same reliability standards, said Robert Thormeyer, director of communications and advocacy at the Utilities Technology Council. “Carriers don’t have the same expectations,” he said.
At the same time, huge data sets made available by smart meters, and the need to keep that data private, make security a priority for utilities now much more than in the past. These changes make greater investment in private telecommunications networks more appealing for many utilities. This includes not only wireless infrastructure, but fiber-based wires, which are more reliable — and more expensive — than copper wires used in the past.
“Many utilities see the value in making an investment” in private communications networks, said Matthew Olson, an engineer with Burns & McDonnell consulting firm and the leader of a working group that focused on communications for Illinois’ NextGrid report. The report gathered input from stakeholders across several sectors, aiming to provide a road map for Illinois’ electric grid modernization in the coming decades.
Utilities can usually spend capital on the infrastructure and make a return on the investment, Olson said. But “several people have pushed back,” he said. Public advocates often question how a utility could be better equipped to build out a communications network than a company that’s dedicated to that purpose.
The NextGrid working group included ComEd and Ameren, as well as researchers like Argonne National Laboratory, consumer groups including Citizens Utility Board, and policy groups such as the Chicago Council on Global Affairs.
A draft version of the NextGrid report notes that some working group members asked why public carriers can’t provide the level of service required by utilities. “Utility representatives noted that it was possible for third-parties to provide this level of service; however, at this time service providers do not want to share the level of detail requested, nor do they want to commit to the level of redundancy and reliability,” the report says. “Common carriers have not invested in the level of service required. A regulation act would be required to realign these interests.”
According to the report, public carriers often don’t prioritize utilities on their wireless networks, meaning that at times of high traffic like during emergencies, critical utility communications risk not getting through. Olson said that Verizon and AT&T in 2018 began offering priority access for agencies that perform critical public safety functions, such as first responders and utilities.
There’s no clear consensus on whether and when utilities should invest in private infrastructure. “It depends on who you ask,” Olson said.
Ultimately, he said, utilities will need a hybrid of public and private network usage, using public carriers where those carriers’ service is adequate, like in cities, and building out their own infrastructure in areas lacking strong cellular service, like rural areas.
Most utilities in Illinois, including ComEd and Ameren, “have large private networks and are migrating as many remaining services to them as possible,” the NextGrid report says.
The service territory and location of the utility also affect the appropriate balance of public versus private infrastructure, Godfrey said. For example, while ComEd is based in Chicago, it’s part of the Exelon Corporation, which operates utilities in several states. So an interconnection between ComEd and PECO Energy Company in Philadelphia would most likely have a combination of private and leased fiber circuits. Interstate private fiber makes the most sense when the utility can place it on an already existing power transmission line, he said.
“ComEd has always invested in communications infrastructure on its system, and these investments will become even more important as the grid evolves,” Paul Elsberg, ComEd’s director of communications, wrote in an email. The investments will be important “to enable the flow of smart meter data, monitor more complex power flows, introduce more automation and respond effectively to changing conditions as more distributed energy and smart devices come on line,” he said.
In addition to fiber, both of Illinois’ major utilities are evaluating cellular long-term evolution, or LTE, capabilities, the report says. These wireless networks will be necessary to integrate new smart devices like inverters, electric vehicle chargers and batteries on the grid, Godfrey said.
Even utilities using private LTE networks will most likely use some service from public carriers, he said. The rapid development of communications technology is “changing the mix,” he said. “There’s never any absolute.”