A european research consortium wants to use a specially developed laser to extract lightning from thunderclouds and make it harmless. The device, which can emit 1000 laser flashes per second with up to 600 gigawatts, was presented in unterfohring near munich, germany.
It was built by trumpf scientific lasers, one of seven project partners. The basic idea is to use the laser to create a plasma channel in the air. This channel conducts electricity very well. That’s why lightning follows it, as the managing director of trumpf scientific lasers, knut michel, explains. "For the blitz, it’s like choosing to drive on the highway or to fight your way through the jungle."The plasma channel, which is to be at least 100 meters long, is laid out in such a way that it guides the lightning to a classic lightning conductor that renders it harmless.
The technology could be interesting for airports, for example, so that they can maintain operations during thunderstorms or to protect sensitive objects such as missile launch pads from lightning strikes. "The damage caused by lightning runs into the billions every year," says michel. Especially in the case of airports, the times when they had to be closed because of the danger of lightning strikes were very significant.
The idea of using lasers to trigger lightning is not new, as michel says. But so far, this has only been achieved in the laboratory, not in nature. The difficulty is to create a sufficiently long and stable plasma channel. For this, a laser is needed that is both powerful enough and emits enough light flashes per second. Previous systems typically achieved only ten laser flashes per second.
In the laboratory, the plasma channel, which comes out of a nine-meter-long structure, can only be seen as a dark, faintly glowing line. The laser itself is in the infrared range and therefore invisible. The only thing you can hear is the product: each of the high-energy laser flashes suddenly heats the air, creating a small pressure wave.
Anna nelles, an expert from the university of erlangen-nurnberg, who has nothing to do with the project, considers the idea of the lightning-conductor laser "certainly worth pursuing," but notes: "it is technically very demanding. Without knowing the exact technical details, I would be rather skeptical that it would work right away."In the end, you have to try out the technology.
This is the plan: the next step will be to test the laser on thunderclouds in a hall in france and, starting in summer 2020, on the summit of the 2500-meter-high santis in switzerland. If this is successful, michel estimates that it will take another ten years before the system is ready for mass production. He estimates the cost of a finished device, which would include not only the laser but also other technologies such as detectors, to be in the tens of millions of euros.