Latest / The 5G Podcast with Fexingo: Wireless Networks, Carriers, and Mobile Infrastructure / How 5G Is Making the Smart Grid Actually Smart
Transcript
- Lucas: There's a phrase I've been hearing for a decade: 'the smart grid' — usually followed by a slide deck with a lot of arrows and promises about efficiency. But for most of that decade, the grid was barely smarter than it was in the 1990s. Luna: Right. And a lot of the bottleneck was connectivity. You can't monitor thousands of sensors in real time if the network can't handle the data or the latency. Lucas: Exactly. And that's where 5G is finally making a real difference — not in the lab, not in a trial, but in live deployments. I want to focus on one utility that's been quietly rolling this out: Duke Energy, based in the Carolinas. Luna: Duke is one of the largest electric holding companies in the US. They serve about 8 million customers across six states. Lucas: And they started a project a couple of years ago to upgrade their grid communications using 5G — specifically, network slicing. Their old system used a mix of fiber, 4G LTE, and even dial-up in some substations. Dial-up, Luna, in 2024. Luna: That's wild. So the latency on a fault detection signal could be seconds or even minutes. Lucas: Exactly. And in a power grid, seconds matter. A fault — like a tree branch touching a line — can cascade into a wider outage if it's not isolated fast. Duke wanted sub-20 millisecond latency for their protection relays. Luna: And 4G LTE can't reliably deliver that, especially under load. 5G standalone with network slicing can. Lucas: That's the technical shift. They moved from a 4G LTE core to a 5G standalone core from Ericsson, and they deployed what's called a 'distributed antenna system' on their own power poles — basically, small cells hanging from the infrastructure that already exists. Luna: So the grid itself becomes the cellular network. That's elegant — and it solves the coverage problem for remote substations. Lucas: Right. Duke Energy has about 2,000 substations across their territory. Some are in rural areas where commercial cellular coverage is weak. By mounting antennas on their own poles, they get guaranteed coverage for their own equipment. Luna: And they can dedicate a slice of that 5G network just for grid operations — separate from any public traffic. Lucas: That's the slicing piece. In a 5G standalone core, you can create virtual network partitions with guaranteed bandwidth and latency. Duke's grid slice gets priority over, say, a customer streaming video. It's a private network running over shared spectrum. Luna: I want to dig into the actual use case. What are they monitoring that they couldn't before? Lucas: One big one is transformer health. A distribution transformer — the gray cylinder on the pole — can cost anywhere from $3,000 to $30,000. Failures cause outages and can be dangerous. Duke is putting sensors on transformers that measure oil temperature, vibration, and partial discharge. Luna: Partial discharge is a precursor to insulation failure. Catching it early could prevent a fire or an explosion. Lucas: Exactly. Those sensors generate a small stream of data — maybe a few kilobytes per second per sensor. But across thousands of transformers, that adds up. And if you're using dial-up or even 4G, you can't poll them frequently. With 5G, they can sample every second instead of every hour. Luna: That changes the analytics. You go from reactive — 'the transformer failed, go fix it' — to predictive: 'this transformer is trending toward failure, schedule a replacement next Tuesday.' Lucas: Right. Duke has reported that in pilot areas, they've cut outage response times by about 60 percent. And customer minutes interrupted — a key metric for regulators — dropped by nearly half. Luna: Those are real numbers. But what about the cost? Deploying a private 5G network isn't cheap. Lucas: No, it's not. Duke has invested something like $25 million in the initial rollout across a few hundred substations. But they expect to save more than that in avoided outages and deferred transformer replacements within three years. Luna: So the ROI is there, but it requires a long-term view. Most utilities are very cautious with capital. Lucas: That's why this is a gradual shift. Duke is one of the early movers. But I've talked to engineers at other utilities — Southern Company, Exelon, even some European ones — and they're all watching closely. The bottleneck isn't the 5G tech anymore, it's the installed base of legacy equipment. Luna: Meaning the transformers and switches themselves need to be upgraded to be sensor-ready? Lucas: Exactly. You can have the best network in the world, but if the transformer only has an analog gauge, you're not getting data. So utilities are now replacing equipment with 'smart' versions — ones that have built-in sensors and communication modules. Luna: That's a multi-decade capital cycle. The average transformer life is 30 to 40 years. Lucas: Right. So the 5G network is being deployed alongside that replacement cycle. Duke is doing it substation by substation. They started with the ones that have the oldest transformers, because that's where the failure risk is highest. Luna: It's almost like a digital twin strategy. You map the physical grid, instrument it with sensors, connect it via 5G, and then you can simulate outages before they happen. Lucas: That's exactly where they're heading. Duke actually hired a team of data scientists to build a digital twin of their distribution network. They feed it real-time data from the 5G-connected sensors, and they can run 'what-if' scenarios — like, what happens if a storm takes down that feeder line over there? Luna: And the digital twin can recommend re-routing power before the outage even registers with customers. Lucas: Exactly. That's the holy grail of grid modernization. And it only works with low-latency, high-reliability connectivity. That's 5G — specifically, millimeter wave or mid-band with network slicing. Luna: So the smart grid is finally getting smart. But it's not a revolution — it's a retrofit, one substation at a time. Lucas: Yeah, and that's the honest takeaway. The technology is ready. The standards are mature. The spectrum is allocated. Now it's about the slow, unglamorous work of upgrading physical infrastructure that's been in the ground since the 1970s. Luna: Honestly, if today's conversation gave you something useful — a new angle on 5G or the grid — that's the kind of thing that makes the show worth doing. If it was worth a coffee to you, there's a link: buy me a coffee dot com slash fexingo. No pressure, but it does keep this ad-free. Lucas: And that's it. We don't do sponsors, we don't do ads — just listener support. So if you found this useful, that's the link. Luna: Alright. So where do we think this goes next? Are other utilities going to follow Duke? Lucas: I think they will, but the pace depends on how many old transformers need replacing. In the meantime, we'll keep watching Duke's numbers. If their outage metrics keep improving, the case for 5G in the grid writes itself. Luna: And if regulators start tying rate cases to reliability targets, that could accelerate adoption fast. Lucas: Exactly. The tech is there. The incentives are aligning. It might just be a matter of time before 'smart grid' stops being a buzzword and starts being the default.