In short: Connected and autonomous freight depends on V2X (Vehicle-to-Everything) connectivity that the UK's public mobile networks were never engineered to deliver. A continuous, low-latency wireless layer alongside the M-network — and along the A-roads that feed it — is the unglamorous infrastructure decision that will decide whether the UK's £124bn road freight sector can platoon, prioritise and pre-empt.
Key Takeaways
- Public 4G/5G has motorway dead zones — coverage along UK motorways is engineered for passengers in services, not continuous data streams from the cab of every HGV doing 56mph in lane one
- V2X needs sub-20ms latency — junction priority, lane-control and emergency braking handshakes are useless if the network round-trip takes longer than the driver's reaction time
- Depots and corridors connect end-to-end — a private 5G depot is half a solution unless the trucks can stay on a managed network from yard exit to next yard entry
In a nutshell
The connected highway is closer than the connected car
Most of the public conversation about connected vehicles is about consumer cars: self-driving Teslas, autonomous taxis, the city centre robotaxi pilots. But freight is moving faster. HGVs follow predictable routes between depots. Their operators have clear ROI cases for fuel saving, accident reduction, and driver-shortage mitigation. And the regulatory path for platooning — two or three trucks driving close behind each other under coordinated wireless control — is further along than for any consumer use case.
The UK has been quietly running connected-freight trials for nearly a decade. National Highways' HelmUK project tested HGV platooning on the A14. Innovate UK's CAVForth programme put autonomous buses on the Forth Bridge. The Department for Transport's Connected & Autonomous Vehicles (CAV) strategy commits to a national V2X infrastructure rollout. What's missing isn't the vehicles or the regulation — it's the wireless layer the vehicles need to talk to each other and to the road.
Why public 5G isn't the answer
When EE, O2, Vodafone and Three rolled out 5G, the coverage maps were drawn around population density. That makes commercial sense — masts go where customers live. But it leaves long stretches of motorway and A-road with either patchy coverage or no 5G at all, particularly in the dips between cuttings, through forested sections, and at junctions where signal multipath is severe.
Even where coverage exists, the public network is engineered for the average user. Latency varies. Backhaul is shared. A truck doing 56mph crosses a cell boundary every 30-90 seconds, and each handover is a moment of uncertainty. For an HGV streaming dashcam footage and a few GPS pings, that's fine. For an autonomous platoon braking together, it isn't.
Private 5G changes the engineering assumptions. The operator picks where the masts go (along the road, not the village). They set the latency budget (typically sub-10ms end-to-end). They control the spectrum (in the UK, Ofcom's Shared Access Licence framework makes it straightforward to license 5G NR for industrial-scale deployments). And they own the backhaul.
Junction priority and signal pre-emption
The most immediate win for connected freight isn't autonomy — it's traffic light priority. A loaded 44-tonne HGV that has to stop at a red light then accelerate again burns significantly more fuel than one that gets a green wave. Bus operators have used signal pre-emption for years; the technology is mature. Extending it to freight needs only two things: a fitted vehicle and a connected junction.
The connected junction is the hard part. Traffic-signal controllers are operated by local authorities, often via legacy SCOOT/MOVA systems that don't speak V2X natively. Bringing them onto a managed 5G network — even just for the corridors that high-volume freight uses — would let HGVs request priority on approach and give the controller the data to grant it without disrupting the wider plan. National Highways estimates corridor-wide priority could cut HGV journey times by 8-15% on congested A-roads.
Platooning and the air-brake problem
Platooning — two or more lorries driving close behind each other so the lead truck breaks the air and the followers save fuel — sounds simple. The hard bit is the brake handshake. If the lead vehicle brakes, the followers need to brake within milliseconds, not seconds. The driver behind isn't reacting to the brake lights any more; the truck is reacting to a network message.
This is where latency stops being a marketing number and starts being a safety number. ETSI's ITS-G5 standard for V2X allows 5G-NR-V2X with sub-10ms latency for safety messages. Public networks struggle to hit that consistently. Trackside private 5G, with masts placed every 1-2km along a corridor and an edge compute node co-located, can hit it routinely.
The UK doesn't yet permit unsupervised platooning on public roads. But the moment it does — and the European Commission's freight-decarbonisation timetable suggests by 2028 — the operators who already have the wireless layer in place will be the ones running the trials.
From depot to depot — without losing connectivity
The most overlooked part of connected freight is the handover between sites and the road. A driver pulling into a depot today drops off the public mobile network and onto the depot's WiFi (or nothing at all). The dispatch system loses telemetry for the duration of the visit. The reefer trailer's temperature log gets uploaded in a burst when the next 4G handshake works. The cargo tracking IoT goes quiet.
A managed private 5G network that covers both the depot and the road corridor outside it solves this end-to-end. The truck stays on the same network from yard exit to road entry, runs on a corridor 5G layer along the route, and rejoins a sister network at the destination depot. Data is continuous. Telemetry is real-time. The dispatch model can plan the next leg before the driver has reached the loading bay.
For a regional 3PL with five distribution centres and 200 vehicles on the road at any one time, that's not a moonshot — it's a series of pragmatic deployments wired together.
What this means for UK transport operators
The UK's £124bn road freight sector is under pressure on every front: driver shortages, decarbonisation targets, e-commerce volumes, and the post-Brexit haulage cost squeeze. The technology that would help — connected vehicles, junction priority, platooning, autonomous yard movements — is real, tested, and ready. What's holding it back isn't the trucks. It's the network alongside the road.
For National Highways and the regional combined authorities, the strategic question is: how do we get a continuous 5G layer along the strategic road network without waiting for the public operators to build it for population centres? For 3PLs and regional hauliers, the practical question is shorter: how do we deploy private 5G in our biggest depots first, and start stitching corridors between them?
We've spent the last few years deploying private 5G in places the public operators wrote off. The strategic road network — outside the M25, between the cities — is the next obvious one.