A super laser will protect us from lightning: tests at the top of the Swiss Alps

THE flash they are as fascinating as they are dangerous, both for the environment (they can trigger accidents) and for the safety of people and things. The climate change that we are already experiencing sadly is, on average, leading to increasingly devastating and violent storms and lightning strikes today. they kill between 6,000 and 24,000 people per year. There are techniques to protect yourself from lightning, but for the moment the best solution remains based on the concept of lightning rod, invented by Benjamin Franklin almost 300 years ago.

The project Laser lightning rod (LLR) of the European EIC FET-Open consortium wants to go further, and for this reason a new type of lightning protection based on the use of a powerful laser shot upwards, capable of capturing and discharging lightning. It is a technique that aims to transfer the charge present in the clouds to the ground in a controlled manner.

Like, how reported by CNN, the technology is now ready for the field test at the Säntis weather station (Switzerland), at an altitude of 2,500 meters. Raising the laser to this height was not easy when you consider that 29 tons of material were transported to the top of the mountain, including 18 tons of concrete blocks to anchor everything securely in the face of the strong winds.

Researchers from the University of Geneva led by Professor Jean-Pierre Wolf lead the European Union-funded consortium which includes the universities of Paris and Lausanne, rocket maker ArianeGroup and German laser maker Trumpf Scientific Lasers, tasked with developing a compact laser source with an unprecedented combination of energy and speed.

“It is one of the places in Europe most affected by lightning,” said Wolf. “There is a radio transmission tower that is hit 100 to 400 times a year. It is therefore an ideal place to do our experiments. “

Lightning is formed when the turbulent air inside a thunderstorm cloud swirls violently around ice crystals and water droplets, snatching electrons from their atoms and creating separate areas with opposing electrical charges. These electric fields can become very strong and because opposite charges attract, they can connect through a discharge of electricity, namely lightning.

The laser imitates and enhances this natural landscape generating an electric field so strong that it directly strikes the electrons of their atoms, creating the opposite charges necessary for the formation of lightning. The idea is to make the clouds discharge lightning in a controlled manner. “That’s why we call them laser lightning rods,” Wolf told CNN. The beam will run alongside the existing transmission tower, which is over 120 meters high.

Traditional lightning rods only protect a limited area of ​​the ground, while lasers it will cover a larger area, although you cannot yet say exactly how much. In addition, the theory is that the laser could not only capture the lightning generated by thunderstorm activity, but also trigger others by discharging the clouds.

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The laser system could be deployable to protect particularly vulnerable installations temporarily or permanently, like “the large crowds that gather on the occasion of events, rockets on the launch pad, storage or transport of hazardous materials from industries, nuclear, chemical, electrical systems, etc. », We read project site. Even the airports could benefit from a similar technology, as the disruption of air traffic due to thunderstorms creates losses in the order of billions of dollars per year in the United States alone.

The laser shoots 1000 times per second and it is so powerful that “a single pulse at maximum power is the same as that produced by all nuclear power plants in the world,” says Wolf, although of course this is only a very short fraction of the time.

The laser will not stay on all the time, but will only activate when increased lightning activity is detected. On the mountain, special photographic equipment will photograph the lightning 300,000 times per second, to see how far the laser beam will follow and at what altitude. “An interesting thing is that due to the high peak power our laser will change color,” Wolf said. “It will turn from red to white as it spreads through the air. It will be really nice to see.”

The tests will last until September. If successful, the next experiment could be at an airport and the technology will be ready in a few years.