The interest in superhot geothermal has grown substantially in recent years. There are few ongoing projects focused on opening these resources for utilization, such as the New Zealand Geothermal Next Generation Project, the Japan Beyond Brittle Project, and the Iceland Deep Drilling Project (IDDP). The IDDP was launched in the early 2000’s. The three biggest power companies in Iceland; Landsvirkjun, HS Orka and OR – Reykjavík Energy, formed a consortium with domestic and international partners to work towards the goal of drilling supercritical production wells. Each of the abovementioned power companies committed itself to drill a superhot ~4.5 km deep well in its production field. The first well of the project, IDDP-1, was drilled in Krafla, N-Iceland. That well was drilled into magma at a depth of 2.1 km. It was possible to do flow tests in that well and it yielded superhot steam. The data gathered in those flow tests were very interesting. It was, however, difficult to handle the fluid due to corrosion and scaling. Moreover, the casing failed and the well had to be abandoned. The second well of the project, IDDP-2, was drilled in Reykjanes, SW-Iceland. That well reached a depth of 4.6 km and core samples were collected from that depth. The casing, however, failed during recovery and the production part of the well is not accessible. The next well of the project, IDDP-3, is now being planned by OR in the Hengill area in SW-Iceland. The main lesson learned from previous IDDP wells is that there are a number oftechnical and geoscientific challenges that must be solved before drilling a deep well. The biggest issue is well integrity and it is evident that a new well design is needed for successfully drilling and operating such a well. OR is now involved in an EU funded project called COMPASS with the goal of developing flexible casing concepts to mitigate thermal stresses and innovative cladding technologies for corrosion resistance of casing pipes. The IDDP consortium has also revisited the goal of the project. Previously the goal was to reach supercritical condition. Now the goal is to reach “superhot” conditions, i.e. drill into a formation where the enthalpy of the fluid is greater than 3000 kJ/kg. The deep heat utilization efforts of OR are not limited to the IDDP concept, i.e. producing fluid from deeper formations. OR is also looking into reaching the energy from deeper formations through deep injection. This concept has been called hybrid superhot EGS and the goal is to reach for the resources below the conventional resources. Injection into superhot formations below the reach of production wells of conventional high enthalpy geothermal field will create and stimulate permeability there. The injected water will then carry the heat from the deeper superhot formation towards the production wells and support the already existing production. The main advantage of the superhot hybrid EGS concept is that it can be achieved using existing well technology. When successful, this method will prolong the lifetime of conventional high enthalpy geothermal projects by enlarging the reservoir downwards and decrease the need for make-up drilling. Moreover, superhot hybrid EGS is an important milestone in developing superhot EGS. This paper will present the deep utilization journey of OR and partners with a focus on future plans, technical challenges and the work already put into solving these challenges.

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