The COMPASS project is inspired by global efforts to improve utilization of geothermal resources by enlarging production fields downwards. Energy output can be enhanced, without the need to expand surface infrastructure, by drilling into deep and hot formations. Calculations indicate that wells drilled into superhot conditions will yield 5-10 times more than a conventional well which can significantly reduce number of wells required.
The main challenges to achieve this are related to the well integrity; due to extreme temperature changes and corrosive fluid chemistry encountered. Two of three wells in the Iceland Deep Drilling Project (IDDP) have already been drilled and had serious problems with casing failures. Numerous examples of casing failures in conventional geothermal wells show that current well concepts, mainly transferred from oil and gas applications, are barely sufficient for geothermal use.
COMPASS will address these challenges by developing improved and innovative well casing technologies:
-To mitigate casing failures, novel foam cement solutions will be developed suitable for high temperature formations. This system would work with available flexible couplings to mitigate high-temperature induced stresses and ensuring well integrity.
- Cost-effective laser-cladding will be used to improve corrosion protection inside the casing pipes.
These technology developments will be enhanced with a robust well design solution addressing challenges, reducing project risk and enabling reduction of LCOE. The new well concept will enable cost-effective geothermal developments in new types of geological settings and new regions.