Lightning-catching drones: Japan redefines storm protection with NTT

Japanese telecommunications giant Nippon Telegraph and Telephone (NTT) has achieved a breakthrough by unveiling the world’s first lightning management system using drones. These “flying lightning rods” can induce and redirect lightning strikes, safeguarding cities and infrastructure from devastating impacts. Successful tests conducted in December 2024 pave the way for a new era in preventing storm damage. Here’s how NTT’s drones work, why they matter, and what lies ahead for the technology.

How Do Drones Catch Lightning?

NTT developed a system that uses drones to actively manage lightning, moving beyond the passive protection of traditional lightning rods. Key components of the technology include:

• Monitoring: Ground-based sensors (field mills) measure the electric field. As storm clouds approach and the field strength rises (up to 2000 volts between the drone and ground), drones receive a signal to take off.
• Drone Design: Each drone is equipped with a Faraday cage, shielding its electronics from lightning strikes. A wire connects the drone to a grounding device via a winch and switch.
• Lightning Induction: The drone ascends to 300 meters beneath storm clouds, amplifying the local electric field to trigger a lightning strike. The lightning hits the drone and is safely conducted to the ground through the wire.
• Durability: The cage withstands discharges up to 150,000 amps (five times stronger than an average lightning bolt). In a test on December 13, 2024, in Hamada City (Shimane Prefecture), a drone survived a strike despite partial melting of the cage and continued flying.

Experiments from December 2024 to January 2025, conducted at 900 meters in mountainous terrain, confirmed the effectiveness of two technologies: drone lightning protection and lightning induction via electric fields. NTT calls this “the world’s first successful lightning management with a drone.”

Why Is This Needed?

Lightning is one of nature’s most destructive forces. In Japan, it causes 100–200 billion yen ($0.7–1.4 billion) in damage annually, harming buildings, power grids, and telecommunications. Globally, the issue is even more severe: in 2025, a single U.S. storm produced 878,000 lightning strikes, and a 2019 lightning-induced substation fire paralyzed Heathrow Airport.

Traditional lightning rods have limitations:

• Coverage: They protect only a small area (about 30–100 meters).
• Installation: Difficult on wind turbines, temporary structures (e.g., field hospitals), or open spaces like stadiums.
• Flexibility: Fixed structures can’t adapt to a storm’s movement.

NTT’s drones address these issues, offering mobile, controlled protection. The company envisions a future where fleets of drones patrol cities during storms, preventing strikes on substations, bridges, and buildings. X users are thrilled: “NTT is turning drones into flying lightning rods—it’s like superhero tech!”

Connections to Other Discoveries

NTT’s technology aligns with 2025 scientific breakthroughs:

• Space Exploration: Studying the evaporating planet BD+05 4868 Ab or lunar soil from Chang’e-6 involves analyzing electric and magnetic fields, similar to those NTT uses for lightning management.
• Climate: Drones can protect infrastructure from increasingly frequent storms driven by global warming, as warned by climatologists in Nature Communications.
• AI and 10G: In Xiong’an, AI and high-speed networks aid weather forecasting. NTT already uses AI to analyze drone video, and its data-processing chips could enhance lightning predictions.

What’s Next?

NTT plans to advance the technology in three directions:

• Forecast Accuracy: Improving lightning strike zone predictions using AI and sensors to ensure drones launch at the right time and place.
• Lightning Energy: Developing systems to capture and store lightning energy (about 278 kWh per strike, or 383.6 TWh globally annually). This could charge an electric vehicle like the Hyundai Ioniq 6 nearly six times per strike.
• Scaling: Creating drone networks to protect cities, airports, and farms. However, X experts question scalability: “One storm—878,000 strikes. How many drones would it take to cover Tokyo?”

In 2025, NTT is also working on drones for agriculture, AI chips, and batteries from recycled materials, underscoring its innovation ambitions, akin to Vivo’s T4 or xAI’s Grok Vision.

Challenges and Criticism

Despite its success, the technology faces hurdles:

• Logistics: Protecting megacities requires hundreds of drones operating in real time. Airspace regulation and coordination are complex challenges.
• Cost: Drones are pricier than fixed lightning rods. Forum critics argue: “If grounding exists, a regular rod is simpler.”
• Reliability: While drones withstood 150 kA, natural lightning can be stronger, and cage damage requires repairs.

NTT counters that drones complement, not replace, lightning rods, especially for temporary or remote sites like disaster-zone hospitals.