The event was literally groundbreaking when Quaise Energy demonstrated its millimeter wave (MMW) drilling technology last month in Houston, Texas. The MMW approach is combined with available oil and gas drilling technology to form a hybrid system expected to expand opportunities for the efficient extraction of deep, superhot geothermal energy resources.

Quaise Energy engineers posit that traditional drilling in the sedimentary layer followed by MMW drilling in the basement layer will achieve deep geothermal energy at higher temperatures and greater power densities. MMW drilling transmits concentrated energy downhole, and the circulating gas effectively removes cuttings from extreme depths. A gyrotron generates powerful, high-frequency MMWs to vaporize basement layers in geothermal formations.

A MMW drilling test conducted at the Quaise laboratory, in preparation for upcoming field demonstrations. Source: Quaise Energy

During the demonstration, 50,000 V DC were delivered to a 100 kW gyrotron connected to a conventional rig. The drilling system operated at approximately 48 kW, burning through granite and basalt at a rate of 0.8 inches (2 cm) per minute.

The company plans deploy this approach to access geothermal hotpots and drill wells ranging from two to 12 miles deep.