Southern Linc CEO says utilities, critical entities at ‘inflection point’ on private LTE

Southern Company is the lone U.S. utility with its own private LTE system, but that could change in the near future, as multiple utilities and other critical-infrastructure entities consider building private LTE networks operating on newly available spectrum, according to Southern Linc President and CEO Tami Barron.

Southern Linc—the Southern Company subsidiary responsible for operating the utility’s mission-critical network that also acts as a commercial carrier—announced plans in 2013 to migrate its 800 MHz system from iDEN technology to LTE. That transition was completed about three years ago, and several other utilities now are evaluating the possibility of building their own private LTE systems on 900 MHz spectrum licensed to Anterix, Barron said during her recent keynote address at IWCE 2022 in Las Vegas.

“There’s a growing interest, and we’re really at an inflection point in this country for utilities and critical infrastructure,” Barron said. “How do other utilities serve their telecommunications needs? One of those options clearly is this idea of private LTE. I think the scales are tipping to more private LTE as we go forward.

“We’ve been doing this for about 26 years at Southern Company, and we were the only utility in this country to do so. We’re seeing an evolution in the industry where others are showing a growing interest in replicating what Southern Linc and Southern Company has done.”

For decades, Southern Company was uniquely positioned among utilities, thanks to its license to 800 MHz spectrum in the southeast U.S. that is the foundation of the Southern Linc system. But now this option is available to utilities nationwide, if they cut a deal to lease 900 MHz broadband airwaves from Anterix, according to Barron.

“We’ve been doing this for about 26 years at Southern Company, and we were the only utility in this country to do so,” she said. “We’re seeing an evolution in the industry where others are showing a growing interest in replicating what Southern Linc and Southern Company has done.”

After securing FCC approval to repurpose 900 MHz LMR frequencies into broadband spectrum in May 2020, Anterix has announced long-term spectrum-lease deals with three utilities—Ameren, San Diego Gas & Electric. and Evergy—worth a total of $128.2 million.

Anterix has not signed a similar agreement with a utility during the last six months. But Barron displayed a slide of “companies actively pursuing private LTE” that featured with the logos of Ameren and 15 other utility firms. Southern Linc is working to help all of these utilities understand all of the implications of private LTE, she said.

“We at Southern Linc are in conversation with all of these guys, because we’ve already done it,” Barron said. “So, we’re offering to use our experience over the last 26 years as maybe a roadmap for their path [forward], and hopefully they’ll even be able to improve on what we’ve been able to do.

“Together, as an industry, we’ll be all the better, once we have others in this private-LTE space. So stay tuned. I suspect you will see that as an ever-evolving opportunity.”

For years, utilities and other critical-infrastructure entities have cited a lack of available licensed, low-band spectrum as the major barrier to entering the private-LTE ecosystem. With the Anterix 900 MHz broadband airwaves as an option, access to spectrum no longer is an insurmountable problem, but that does not mean that committing to building a private LTE network is a simple decision for utilities or other critical-infrastructure entities, Barron said.

“Clearly, access to spectrum is just part of the equation,” Barron said. “All of you know … what it takes to construct a very large wide-area network. It took us over six years, with a lot of work. Utilities are ill-equipped to be able to do that.

“The other thing that maybe is even more important is having a qualified and experienced workforce, in order to continue to operate and maintain that network, so that it meets mission-critical standards—that’s a little bit of a heavy lift for utilities.”

Barron also outlined the measures that Southern Linc has taken to ensure that the LTE network supporting the Southern Company utility meets mission-critical standards, including geo-redundant cores in Atlanta and Birmingham, Ala., that each have two generators with enough on-site fuel to support 14 days of backup power.

“And they’re encased in a Category 5 hurricane-proof shelter—we are in the southeast,” Barron said.

Hardening that enables network independence also are key characteristics of the 1,200 Southern Linc cell sites and backhaul, Barron said.

“We have connected all of the backhaul onto Southern Company-owned fiber assets,” Barron said. “[For] our connectivity at the cell-site level, we’re able to use our company-owned assets. We have utilized third-party fiber for last-mile [connectivity], but we’re actively working to replace that with our company-owned fiber. And that [company-owned] microwave network … is also used.

“We have cell-site redundancy—from a last-mile [standpoint]—at probably 80% of our cell sites. Interestingly, at every cell site, clearly we have battery backup to about eight hours. But we also have on-site fuel-cell or [power] generation to the tune of five days.”

Such measures are an indication of the Southern Company-Southern Linc commitment to “resiliency, reliability and security,” Barron said.

Ensuring that an LTE network meets mission-critical standards also is expensive, she said.

“It’s not cheap,” Barron said. “There are much cheaper paths to go.”

But the investment in Southern Linc has proven worthwhile to the Southern Company utility parent because the hardened LTE system has helped minimize power outages associated with the numerous hurricanes and other damaging storms that have hit the southeast U.S. in recent decades.

Such natural events “have repeatedly demonstrated the gaps in reliance on public LTE networks” that have sustained service outages for weeks at a time on occasion, Barron said. Such lengthy communications problems simply cannot happen for large utility like the Southern Company to do its job properly, she said.

“In order to restore electric service, you have to have effective, reliable communications,” Barron said.

Modern communications enabled by private LTE system also are needed to support many smart-grid applications that optimize the use of renewable energy sources. In addition, they also can give utilities access to stronger cybersecurity tools at a time when there are regular reminders that sophisticated cyberthreats on critical infrastructure is an ever-present concern.

“You have a need in the ever-evolving utility industry for everything from ever-increasing security cyberthreats—which are significant, especially today—as well as the need to evolve our electric-grid operations and response to positive influence on climate change,” Barron said.