The objective of the "Drilling in dEep, Super-CRitical AMBient of continentaL Europe" (DESCRAMBLE) project is to demonstrate the feasibility of extracting electricity from super-critical deep geothermal reservoirs. Water reaches super-critical conditions when the temperature and pressure is higher than 374°C and 218 bar respectively. The main motivation for the project is that the electrical power generation from super-critical geothermal wells is estimated to increase the power output by a factor of 10 thereby reducing the number of wells needed per MWe production. Drilling costs represent a substantial part (30-50%) of a hydrothermal geothermal electricity project, reducing the number of wells needed will therefore increase the competitiveness of such projects
Currently there are no available logging tools that can be used to measure the thermal response and conditions in a super-critical well at operating conditions. The Harsh Environment Instrumentation group at SINTEF ICT is therefore developing a logging tool that will characterize the well profile with parameters such as pressure and temperature. The group has extensive experience with instrumentation for the oil and gas industry that can be extended into the geothermal domain. The tool consists of newly developed high temperature electronics, sensors and batteries encased in a custom made, high-performance heat shield. The main research challenges are:
· Develop and manufacture a Dewar flask (heat and pressure shield) with sufficient performance
· Push the state of the art in high temperature electronics by developing and verify an electronics platform that allows for operation above 200°C, aiming at 300°C.
· Sensor selection and integration
· Test novel battery solutions that allow for operation above 200°C
After successful lab-testing the tool will be field tested in the drilled well in collaboration with global green energy producer Enel Green Power who is coordinating the project.