NTT Celebrates a Lightning Strike on Its Drone — As It Looks to Harvest Energy From the Clouds

Japan's NTT Corporation is celebrating having one of its drones struck by lightning — because that's exactly what it was hoping for, in the first successful demonstration of drone-based lightning triggering and guidance.

"Lightning strikes are one of the most destructive natural phenomena affecting human society. While the NTT Group has implemented various lightning protection measures for critical infrastructure — including telecommunications facilities — lightning-related damage remains a persistent issue," the company explains. "At NTT, we are exploring the use of rapidly advancing drone technology to create a new approach: 'drone-triggered lightning.' This method involves flying drones into optimal positions beneath thunderclouds to actively trigger lightning strikes, and then guiding the discharge safely away from vulnerable areas."

While having your precious drone struck by lightning sounds like a terrible thing to happen, NTT's drones are built for the purpose: a quadcopter is installed within a lightning protection cage and flown towards the clouds while trailing a conductive wire. The push of a switch connects the wire to ground — and, in a December 2024 test in Hamada City, triggered a lightning strike.

"Just before the lightning strike, it was confirmed that a voltage of over 2,000 volts had developed between the wire and the ground," NTT says of the experiment. "This rapid increase in local electric field strength triggered a lightning strike directed at the drone. This marks the first successful case in the world of triggering lightning using a drone. At the moment of the strike, a loud cracking sound was heard, a flash was observed at the winch, and partial melting occurred in the drone's lightning protection cage. However, the drone equipped with the protective cage continued to fly stably even after the lightning strike."

Tests revealed that the custom-designed protection cage, compatible with commercial off-the-shelf drones, can provide protection for strikes of up to 150kA — some five times greater than natural lightning strikes. The ability to trigger a strike, meanwhile, provides a way to drain the charge before it builds up and strikes buildings, trees, or anything else that might be damaged — and NTT is working on taking the energy and harvesting it for later use, suggesting that the power of lightning could be used to charge batteries including those used in electric vehicles.

The company's full write-up is available on the NTT website.