While current geothermal setups work at temperatures not exceeding 392° F, Quaise Energy has been working on new technology capable of tapping into geothermal energy by using microwaves to vaporize rock.

Source; Quaise Energy

“MMW Drilling is advantageous because the process operates mostly independent of depth, unlike conventional drilling, and is particularly optimized for the types of rock encountered in the deep basement of the crust where high-grade geothermal heat is expected,” Matthew Houde, co-founder of Quaise Energy, explained.

According to the company, Quaise Energy is hoping to tap into regions where the rock hits temperatures over 700° F and water that seeps in at these temperatures would become capable of carrying three to four times more energy than regular hot water. Consequently, when brought to the surface to run turbines, it would reportedly produce up to three times more electricity generation.

To accomplish this, Quaise is using its millimeter wave (MMW) drilling — which relies on a continuous beam of energy waves between 30 GHz to 300 GHz (millimeter waves) to melt, vaporize and bore through extremely hard rock — because the drills used by the oil and gas industry are not used at such temperatures and pressures. However, there are obstacles to this approach, with Quaise explaining that no geothermal energy system has tested these depths before. Because the company is unsure about how water will behave when it encounters such super-high temperatures, Quaise Energy is researching the best models for such an approach.

Instead of using the most common approaches for injecting water — first through a closed-loop system wherein water is introduced through a pipe, heated through a network of horizontal pipes and then forced out through another pipe; and second wherein two horizontal wells located within a system are comprised of hundreds of manmade fractures in the rock — Quaise Energy intends to refine these approaches by introducing microcracks where the two wells are connected by a “large cloud of permeability rather than large fractures.”