Drilling rocks with laser: Sci-Fi or reality?

To fully leverage geothermal potential and capitalize on its numerous benefits, it is essential to enhance drilling speed. To this end, the DeepU Project is investigating the application of an innovative laser technology for the drilling of deep geothermal wells. This work presents the latest results from laboratory-scale laser drilling experiments utilizing a newly designed and manufactured drilling system. This technology includes a high-power laser source and optics, a drilling string, a drilling head, a flushing system and a few secondary systems necessary for successful rock penetration. Laser-rock interactions were investigated and examined in three series of experiments revealing the complexity of dynamic processes such as thermal spallation, melting and vaporization in granite, sandstone and limestone. These phenomena were studied and quantitatively characterized with state-of-art analytical techniques like thermography, photogrammetry. Moreover, the DeepU laser system was successfully tested proving its effectiveness in rock drilling operations.