Deep geothermal

Deep geothermal is a process that involves extracting heat from below the earths surface at depths of between 150 and 5,000 metres. Shallow or standard geothermal is accepted as being at depths of less that 150 metres.

The possibility of drilling deep in to the earths core beyond 150 metres only become a reality with a Boston-based MIT spin-off, Quaise energy who have developed an ultra-deep drilling technology. This repurposed technology is millimeter-wave beam technology which was originally developed to superheat plasma in fusion experiments. It effectively blasts its way through rock far below the Earth's surface that was previously not possible to drill through.

Whilst Geothermal power is a well known accepted alternative energy source, at depths of 150 metres or less, the maximum temperature achieved is 30°C, which gives a thermal capacity of 10 kW to < 5 MW but can also provide cooling. These kinds of levels are useful in the provision of renewable heat sources, however do not provide the option of electricity generation.

At depths of between 150 and 5000 metres temperatures can increase to beyond 200°C. From 90 °C – 200°C electrical power generation is possible whilst anything over 200°C allows for direct heat use for electrical power generation. At depths where rock temperatures reach 500 °C water can be heated to a "supercritical" state which massively improves the efficiency of the process of extraction.

External links

• https://www.quaise.energy

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