Latest / The 5G Podcast with Fexingo: Wireless Networks, Carriers, and Mobile Infrastructure / How 5G Is Quietly Redesigning the Electrical Grid
Transcript
- Lucas: So if you ask most people where 5G is making a difference, they'll probably say faster phone downloads or maybe connected cars. But one of the most quietly transformative applications right now is happening on the electrical grid. Luna: You mean using 5G to manage power distribution? I've seen a few headlines, but it feels like it hasn't gotten much mainstream attention. Lucas: Exactly. And it's not just a theoretical use case. Duke Energy in North Carolina has been running a pilot program since early 2025 where they're using 5G-connected sensors to monitor voltage and load on distribution transformers. Not the big transmission towers you see on highways — these are the gray canisters on poles in your neighborhood. Luna: And what's the problem with those transformers today? Are they not monitored? Lucas: Most of them are completely dumb. A utility might know the total load on a substation, but they have no idea what's happening at the individual transformer level until something fails. So they either over-engineer them — which is expensive — or they wait for a brownout. Duke's pilot put 5G modules on about 200 transformers in a suburban area near Charlotte. Luna: And what did they learn from the data? Lucas: They found that during peak hours, some transformers were running at 95 percent capacity while others in the same neighborhood were below 50 percent. That's a massive imbalance. By rerouting load using automated switches — also controlled over the 5G link — they reduced peak load on the most stressed transformers by about 15 percent. That defers the need to replace them, which can cost anywhere from ten to fifty thousand dollars per unit. Luna: Fifteen percent is significant. And why 5G specifically? Why not Wi-Fi or wired connections? Lucas: Great question. Wi-Fi doesn't have the range or reliability for devices scattered across a several-mile radius. And wired connections — fiber or copper — are too expensive to run to every pole. Plus, many of these transformers are in hard to reach places. 5G, especially in the mid-band spectrum, gives you wide coverage, low latency, and the ability to handle thousands of devices per square kilometer. That's exactly what you need for a distributed grid. Luna: And the latency piece matters for safety, right? If you're tripping breakers or isolating faults, you need near-instant response. Lucas: Right. With network slicing, a utility can carve out a dedicated portion of the 5G network that guarantees latency under 10 milliseconds for protection relays. That's comparable to a dedicated fiber line. The 3rd Generation Partnership Project — the standards body — actually introduced specific features in Release 17 for what they call 'time-sensitive networking' over 5G. So this is built into the spec, not a hack. Luna: That leads to something I've been wondering about: security. Utilities are understandably paranoid about remote control of grid equipment. How do they trust 5G? Lucas: It's a real concern. The approach Duke and others are taking is to run the 5G network as a private, standalone core — not a slice of the public network. That means the data never touches the open internet. It's a bespoke 5G network, often called a non-public network, that operates on licensed spectrum the utility leases from a carrier or even gets from a local spectrum arrangement. The encryption and authentication are baked in at the SIM level. Luna: So it's like having your own cellular network, but with 5G speeds and capacity. That sounds expensive. Who's paying for all this? Lucas: The business case hinges on avoided capital expenditure. Duke estimated that deferring just one transformer replacement per neighborhood saves enough to pay for the 5G modules in a couple of years. Plus, regulators are increasingly allowing utilities to include grid modernization costs in the rate base. The US Department of Energy also has grants for smart grid pilots. So the upfront cost is becoming manageable. Luna: And it's not just the big investor-owned utilities. I've read that some rural electric cooperatives are jumping directly to 5G because they don't have any existing automation infrastructure to rip out. Lucas: That's a key point. For a co-op serving a thousand customers across a hundred square miles, running fiber to every substation and pole is impossible. But a single 5G base station can cover much of that area. They can skip the wired era entirely. In fact, the National Rural Electric Cooperative Association has been working with a few vendors on reference architectures for private 5G in rural grids. Luna: Let me play devil's advocate: how resilient is a 5G-based grid during a natural disaster? If a hurricane takes out the cell towers, you lose both power and the network that's supposed to help restore it. Lucas: It's a valid risk. The answer is that utilities are designing for failure. They're keeping hardened microwave links as a fallback for the most critical substations, and some are even looking at satellite backhaul for the 5G small cells. But you're right — reliance on cellular networks does introduce a new failure mode. The trade-off is that during normal operations, you get much better visibility and control, which actually helps reduce outage duration overall. Luna: There's also the broader trend of distributed energy resources — rooftop solar, battery storage, electric vehicle chargers. That makes the grid much more complex to manage. Lucas: Absolutely. The old model was one-way power flow from central plants to consumers. Now you have bidirectional flows. A neighborhood with a lot of solar might send power back to the grid during the day and draw heavily at night. 5G enables what's called a virtual power plant — aggregating thousands of distributed batteries and solar inverters and controlling them as if they were one large generator. The California Independent System Operator has already run trials using 5G to coordinate EV charging stations to absorb excess solar. Luna: That's fascinating. And it ties into the network slicing idea again — you'd need a low-latency slice for the control signals and a high-bandwidth slice for the sensor data. Lucas: Exactly. One physical network, multiple logical networks with different performance characteristics. The International Energy Agency projects that by 2030 there will be about 50 billion connected devices on the grid worldwide. Not all of those will use 5G — many will use LPWAN technologies like nb iot or LoRaWAN for simple sensors. But the devices that need high bandwidth or ultra-low latency — like video inspection drones for transmission lines — will lean on 5G. Luna: And if today's conversation gave you something usable — maybe a fresh way to think about 5G, or a concrete example to bring up at work — that's exactly the kind of thing that keeps us going. If you ever want to support the show, we're listener-supported and ad-free. You can buy me a coffee dot com slash fexingo. No pressure at all, just a way to keep these deep dives coming. Lucas: Yeah, I'll echo that. It's a small gesture that goes a long way in helping us keep the podcast independent. So back to the grid: I think one underappreciated aspect is how 5G can help integrate renewable energy more smoothly. Luna: Because solar and wind are intermittent, and the grid needs to balance supply and demand in near real time. Lucas: Right. With 5G-connected inverters, a utility can curtail solar output within milliseconds if frequency rises too high, instead of having to disconnect entire solar farms. That reduces wear and tear on equipment and keeps more renewable energy on the grid. In Germany, where renewable penetration is high, they're already using cellular-connected ripple control receivers, but those are based on older 3G and 4G networks. The migration to 5G brings better reliability and lower latency. Luna: There's also the maintenance angle. Instead of sending a truck to visually inspect every transformer, you get alerts when a transformer's oil temperature or vibration pattern changes. That's predictive maintenance. Lucas: Exactly. Duke Energy's pilot included vibration sensors that can detect early signs of mechanical failure. One transformer showed unusual harmonics a full three weeks before a bearing would have seized. They replaced it during a scheduled outage instead of during a crisis. That's the kind of operational saving that's harder to quantify but adds up. Luna: So where does this go next? Are we going to see every utility building its own 5G network? Lucas: I think not every utility will go the full private network route. For smaller ones, a network slice from a public carrier with strong SLAs might be enough. But the technology is evolving fast. There are now compact 5G core solutions that can run on a server in a substation. And the chipsets for the end devices — the modules that go on the transformers — are dropping in price. We're seeing them below $50 already, and they'll probably hit $20 in the next two years. Luna: That's the kind of cost curve that unlocks mass adoption. When a sensor costs more to install than the sensor itself, you reach a tipping point. Lucas: Exactly. And the spectrum situation is improving too. In the US, the FCC recently opened up the 3.5 GHz band for utility use through the Citizens Broadband Radio Service. That gives utilities access to a slice of mid-band spectrum without having to win an auction. It's a game changer for rural co-ops. Luna: So to wrap up: 5G isn't just about faster phones. It's becoming the nervous system for a grid that's getting more complex, more distributed, and more renewable. And the pilot projects are already showing real results. Lucas: Right. The Duke Energy pilot alone showed a 15 percent load reduction on stressed transformers. That's not a theory — that's operational data. And as the technology matures, the grid of the future will be not just smart, but wirelessly smart, with 5G as its backbone. It's one of those quiet revolutions that will affect every home, but most people will never see it. Luna: And that's sort of the point. The best infrastructure works invisibly.