What other deep drilling and ultra-hot geothermal projects are underway globally?
Critical temperatures have been encountered in deep drilling projects in countries including Iceland, Italy, Japan, Kenya, Greece, USA and Mexico. But few have simultaneously reached and confirmed pressure and temperature of the geothermal fluid present at conditions higher than the critical point.
Iceland Deep Drilling Project (Iceland)
The IDDP (2000 – ongoing) aims to find out if it is economically feasible to extract energy and chemicals out of hydrothermal systems at supercritical conditions. Advanced drilling technology is being applied and novel fluid handling and evaluation systems designed. The IDDP-2 well was able to go beyond the critical point for the saline geothermal waters deeper in the Reykjanes reservoir encountering a temperature of 427°C at depth of approximately 4600m.
The DEEPEN project (2021-2024) aims to increase the probability of success when drilling for geothermal fluids in magmatic systems, through the development of improved exploration methods and frameworks for the joint interpretation of exploration data using a Play Fairway Analysis methodology.
The FORGE (Frontier Observatory for Research in Geothermal Energy) programme is designed to assist in ultimately enabling the building of large-scale, economically sustainable Enhanced Geothermal System (EGS) systems for heat extraction from underground formations. This US EGS project is now into phase three at the Milford site in Utah, with well drilling a significant part of this phase. Near term goals aim to perfect drilling, stimulation, injection-production, and subsurface imaging technologies required to establish and sustain continuous fluid flow and energy transfer from an EGS reservoir.
The Clean Air Task Force (USA)
This US organisation, operating for over 25 years, has a focus on decarbonising the energy system. They have recently commenced activity in super hot rocks and deep geothermal, and are looking to have three phases to their super hot rocks activity: phase 1 is developing technology, including drilling 3 to 7km wells; phase 2 is commercial deployment, whilst also extending the reach of drilled depths to 10km; and phase 3 aims to unlock super-deep geothermal across the globe at depths of 10-20km.
Development of Subduction-OriginSupercritical Geothermal Resources (Japan)
Since 2017, the New Energy and Industrial Technology Development Organisation (NEDO) has been seeking to utilise 400 to 500°C supercritical fluid at a depth shallower than 5km. Earlier work suggested supercritical geothermal resources may exist in/around many of the volcanic zones in Japan, with the potential of possibly several tens of gigawatts. 2040 is targeted for the operation of a pilot plant. The first phase of the project was completed in 2020 and the second phase began in 2021 to select a region for deep drilling in the phase. A paper on Japan supercritical was presented at the WGC 2020+1.
Newberry Super-Hot EGS Project (USA)
This project proposes an EGS proof of concept at a location where very hot rocks are close to the surface (~5 km). Drilling into the brittle-ductile transition aims to test the efficiency of thermally induced fracturing and reservoir creation as well as the development of drilling techniques and borehole instrumentation adapted to high temperature. A paper outlining this project was presented at WGC 2020+1.
The KMT project has the ambition of establishing research infrastructure able to access a magma chamber and initiate a 30-year scientific programme for observations and experiments in magma dynamics, volcanic risk, and “extreme” geothermal energy.
GEMex (EU, Mexico)
This collaboration between Europe and Mexico (2016-2020), funded by the European Commission through Horizon 2020, worked to research the potential use of two types of “unconventional” geothermal resources inMexico; an Enhanced Geothermal System (EGS) at Acoculco, and the Super-hot Geothermal System (SHGS) at Los Humeros. The final project reports can be accessed.
This international project (2015-2018), undertaken within the Larderello geothermal field in Italy, aimed to encounter supercritical geothermal conditions. The Venelle-2 well, a dry well drilled to 2200m was extended as part of the DESCRAMBLE project to 2810m encountering temperatures of more than 500°C.
This European Horizon 2020 project (2015-2020) aimed to demonstrate the feasibility of EGS for delivering energy from renewable resources within Europe. Three different resource systems have been selected to represent different locations and geological formations in Europe.
In addition to the above selection of projects, there are a range of international collaborations and consortia based on shared research and development interests: