For those wondering: they’re talking of 25 milliwatts of energy per square meter, so the (theoretical) 20 times increase would be half a Watt per square meter (source: <a href="https://cosmosmagazine.com/physics/seductive-light-from-the-dark-side" rel="nofollow">https://cosmosmagazine.com/physics/seductive-light-from-the-...</a>)