On a treeless ridge more than 4,000 metres above sea level in southeastern Tibet, there is no road, and in many places no reasonable way to build one; the terrain is too steep and ecologically fragile. Yet the ridge sits on the route of one of China’s most ambitious power projects: an around 800-kilovolt ultra-high-voltage direct current (UHVDC) line, roughly 2,681km long, carrying electricity from Tibet across Yunnan and Guangxi to the Guangdong-Hong Kong-Macao Greater Bay Area, at a reported cost of about 53.2 billion yuan. It is China’s first ultra-high-voltage line to cross the Qinghai-Tibet Plateau, with construction underway since 2025 and completion targeted for 2029.
Getting steel tower components up to that ridge became almost as hard as building the line itself. On September 21, 2026, engineers from the State Grid Power Engineering Research Institute, with a construction team from State Grid Henan Electric Power Construction Company, ran a trial that offered one answer: a tethered balloon.
The 25-metre-diameter, 8,000-cubic-metre balloon relies mainly on helium buoyancy, while a ground-based tethering system steers it along a planned route to the work site, carrying up to two tonnes of material. Institute engineer Tu Dejun said its advantages over conventional transport include a heavier payload, longer time aloft, and less disturbance to the ground.
It is worth asking why this trial happened. Cutting a road into remote high terrain is not simply expensive — it can also disturb fragile slopes and increase engineering and environmental risks. Helicopters reach almost anywhere but carry limited loads at high cost. Heavy-lift drones are improving but still struggle with sustained multi-tonne cargo. Cableways move freight efficiently along a fixed line but need substantial infrastructure and are hard to relocate as work sites shift.
China used a cargo balloon to solve the logistics of building in the mountains
The balloon appears designed to fill this gap: it does not necessarily require a permanent road or cableway, can carry a heavier payload than many conventional drones, and may offer greater flexibility than a fixed ropeway. It is not, on present evidence, a replacement for any of these — rather a complement, in conditions where roads and cableways are least practical.
State Grid frames the balloon as one part of a broader “low-altitude transport” toolkit it has been assembling for grid construction, alongside heavy-load drones and cargo airships, as part of a wider push to mechanise remote, high-altitude work. That framing matters more than the balloon itself: it treats the movement of construction materials, not just the structure being built, as an engineering problem worth solving in its own right.
Pakistan’s own experience illustrates the same point. The Karakoram Highway (KKH), the principal land link between Pakistan and China, runs through unstable terrain. In January 2010, a landslide near Attabad in Hunza dammed the Hunza River, submerging roughly two dozen kilometres of highway and cutting off tens of thousands of people.
Restoring the route required five new tunnels totalling 7.12km, 78 culverts and two bridges, at a cost of over $275 million. More recently, sections of the Karakoram Highway between Thakot and Raikot have required realignment because of dam construction along the Indus River. The current PSDP FY27 lists a 102km relocation project, with an estimated cost of Rs502.6bn and financing from the China Export-Import Fund. Such projects illustrate the broader challenge of moving cement, steel, machinery and other construction materials through terrain that is itself a major logistical constraint.
None of this means China intends to deploy tethered balloons on the KKH, or that Pakistan has adopted the technology — no evidence supports either claim; this remains a single experimental use tied to a power project in Tibet. But CPEC’s second phase is increasingly being framed around industrial cooperation and technology transfer, including the proposed ‘Innovation Corridor’.
Within that broader push, it is fair to ask a narrower question: could emerging high-altitude logistics technologies eventually be worth examining through feasibility studies for the hardest, least accessible stretches of Gilgit-Baltistan’s network, where roads, cableways and helicopters all face practical limitations? That is a question for future research, not a forecast of deployment.
The more interesting claim in this Tibetan trial has little to do with balloons as such. It is that connectivity depends not only on the infrastructure that gets built, but on the far less visible problem of moving the materials needed to build and maintain it. Whether balloons, drones, airships or something not yet invented prove to be the right tool in any given mountain range, the lesson for Pakistan, China, and every country building in difficult terrain is the same: the future of connectivity may depend as much on how materials reach a construction site as on what eventually gets built there.
The writer is a Research Associate at the Centre of Excellence for CPEC, PIDE
Published in Dawn, The Business and Finance Weekly, October 5th, 2026
