2026-05-02
There are roughly 6 billion kilometers of copper wire installed globally — in walls, underground, undersea, and strung between poles. Fiber optics already dominate long-haul telecommunications, but what if we went all the way and eliminated copper entirely? Every Ethernet cable, every phone line, every last-mile connection — pure glass.
First, the obvious win: bandwidth. A single modern fiber strand carries 100 Tbps over tens of kilometers. Cat 6A copper tops out at 10 Gbps over 100 meters. But bandwidth isn't why this thought experiment gets interesting. The interesting part is weight, fire risk, and theft economics.
The weight calculation: Standard Cat 6 cable weighs about 40 kg per kilometer. Equivalent-capacity fiber (with protective jacket) weighs roughly 4 kg/km. A typical commercial building has 50-80 km of structured copper cabling. Replacing it saves 2,000–3,000 kg per building. Across the estimated 6 million commercial buildings in the US alone, that's on the order of 12–18 million metric tons of copper freed up. Global copper reserves are about 870 million metric tons — we'd be returning roughly 2% of known reserves to the supply chain.
The power delivery problem: Here's where the dream dies. Fiber can't carry electrical power. Every endpoint device — access points, cameras, phones, IoT sensors — currently relies on Power over Ethernet (PoE), delivering up to 90W per port. An all-fiber world requires either:
PoF exists today but the numbers are brutal. Laser-to-PV conversion efficiency tops out around 30%. Fiber attenuation for power-delivery wavelengths (800-850 nm) is about 2.5 dB/km in multimode fiber. For a 100-meter run delivering 15W to a device, you'd need to inject roughly 50W at the source — and that's with specialized large-core fiber, not the telecom glass you're using for data. A standard 9-micron single-mode fiber can safely carry only about 1-2W before nonlinear effects and fiber fuse risk become real concerns.
Fiber fuse is genuinely terrifying: above ~1.5W in single-mode fiber, a self-propagating thermal destruction front travels back toward the laser source at 1-3 m/s, vaporizing the core as it goes. Your cable literally eats itself.
The theft angle: Copper theft costs utilities an estimated $1 billion annually in the US. Fiber has essentially zero scrap value. A world without copper infrastructure would eliminate an entire category of infrastructure crime overnight. No more substations stripped bare, no more rail signal cables yanked out causing derailments.
The electromagnetic immunity bonus: Fiber is completely immune to EMI, lightning-induced surges, and ground loops. In industrial environments and hospitals, this alone justifies hybrid architectures. No more shielding, no more isolation transformers, no more mysterious packet loss when the elevator motor kicks in.
What would actually work: A hybrid architecture — fiber for all data transport, with thin DC power buses (possibly superconducting in large installations) running in parallel. You don't eliminate copper; you minimize it to pure power delivery, where its conductivity (59.6 × 10⁶ S/m) remains unmatched by any practical alternative except silver.