Laser technology to protect critica… – Information Centre – Research & Innovation

Lightning strikes can lead to considerable destruction to properties and essential infrastructure, these types of as airports. To mitigate this risk, one EU undertaking is attempting to use strong laser know-how to control where lightning strikes. If successful, the ensuing laser lightning rod could aid save funds – and lives.


© stnazkul #84059942, 2020

It is reported that lightning never strikes the exact same location two times. But just one strike can be enough to lead to considerable destruction. Not only do lightning strikes kill up to 24 000 persons each and every calendar year, they’re also dependable for electrical power outages, forest fires, and structural destruction.

When lightning strikes crucial infrastructure and sensitive websites like airports and rocket start pads, the end result can be billions of euros in destruction. To mitigate this risk, the EU-funded LLR undertaking has set out to do what was at the time viewed as unattainable: control lightning. 

“Today’s lightning protection methods are however primarily based on the lightning rod developed by Benjamin Franklin pretty much 300 years back,” suggests Aurélien Houard, a researcher at Ecole Polytechnique in France and LLR (Laser Lighnting Rod) undertaking coordinator. “Our undertaking intends to update this principle utilizing a pretty strong laser.”

A strong laser beam

At the heart of the undertaking is a novel variety of laser showcasing a strong beam. This beam will act as a preferential route for the lightning, diverting it away from possible victims. The exceptional laser will also information lightning flashes to the ground to discharge the electric powered demand in the clouds.

To illustrate, when installed at an airport, the laser lightning rod would run in conjunction with an early warning radar technique. “Upon the development of thunderstorm disorders, the laser would be fired towards the cloud to deflect the lightning strike away from plane for the duration of acquire-off, landing, taxiing, and ground functions,” points out Houard. “In outcome, this would create a secure corridor surrounded – and shielded – by lasers.”

Floor-breaking know-how

To obtain the essential depth and repetition rate, the undertaking has utilized a quantity of ground-breaking technologies. For instance, it makes use of chirped pulse amplification (CPA), the present-day-state-of-the-art system made use of by most of the world’s large-electrical power lasers and the winner of the 2018 Nobel Prize in Physics. “CPA is a system for amplifying an ultrashort laser pulse,” suggests Houard. “It performs by stretching out the laser pulse temporally, amplifying it, and then re-compressing it.”

To provide the short laser pulses at a large repetition rate of 1 000 shots for each 2nd, the undertaking team experienced to scale up the laser’s ordinary electrical power. To do this, highly developed amplification know-how developed by Trumpf, a German industrial device production company and member of the undertaking consortium, was made use of.

In accordance to Houard, the electricity equipped by the technology’s numerous diodes is concentrated in a pretty skinny disk of crystal cooled by h2o. “When the laser pulse goes nevertheless the crystal, the saved electricity is transferred to the laser pulse via a quantum mechanism termed ‘laser gain’,” he suggests. “The style of this skinny disk amplifier permitted for an raise in the electrical power of the ultrashort laser by an get of magnitude.”

The undertaking also developed an progressive technique for predicting lightning exercise. “Using a blend of conventional info from climate stations and artificial intelligence, the partners developed a new way of predicting lightning strikes in just a forecast interval of ten to thirty minutes and in just a radius of thirty kilometres,” remarks Houard. “This is the to start with time that a technique primarily based on straightforward meteorological info has been equipped to forecast lightning strikes via authentic-time calculations.”

Demonstration prepared for 2021

The LLR team is now tests the laser in Paris, with the intention of validating the principle of properly guiding a lightning strike to the ground by projecting a prolonged-array beam into the atmosphere.

A last demonstration of the LLR principle is set to acquire location on Mt. Säntis in Switzerland, which is household to a Swisscom tower that is struck by lightning over 100 periods each and every calendar year. The demonstration is prepared for 2021. Subsequent a successful demonstration, the undertaking team is self-confident that the technique will be all set for total commercialisation in just a handful of years.