German impacts, page-379

How can engineers better drill into the depths of the earth?

https://www.pm-wissen.com/technik/a/wie-koennen-ingenieure-besser-in-den-tiefen-der-erde-bohren/14587/

Quotes: "Much more frequently, however - in about 30 percent of wells - the targeted vein is simply missed, so that no water can be extracted. This so-called discovery risk is a major challenge when it comes to further developing geothermal energy as a reliable, climate-friendly and inexpensive energy source of the future."

"Researchers at the Fraunhofer Institute for Energy Infrastructures and Geothermal Energy (IEG) in Bochum have now come up with a possible solution. A drilling turbine - as small as a glue stick - is to be lowered down the main borehole on a high-pressure water hose."

"Using a special mechanical deflection device, this design is able to deviate at angles of up to 45 degrees and advance into the surrounding area. With several attempts, it can thus perforate the ground within a radius of up to 50 meters around the main borehole and significantly increase the catchment area. Water-bearing fractures and fissures that were originally missed are thus tapped for heating water production after all."

"The Micro-Turbine-Drilling (MTD) system consists of a tungsten carbide microdrill only about 3.5 centimeters thick and ten centimeters long with diamond grains incorporated. It rotates at up to 80,000 revolutions per minute and penetrates up to three meters per hour through even the hardest granite. The water that powers the microturbine also serves to cool and remove the drilling dust."

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