Geothermal energy is one of the most underutilized renewable sources. This is mainly due to high investment costs and a rather long development cycle. The big part of the investment costs, i.e. approximately 53 % (other sources indicate between 30 and 70%), lies in drilling operations. The European Union’s Horizon 2020 Geo-Drill project aims to develop more “holistic” approach for drilling technologies, which will potentially reduce the cost of drilling to much greater depths (>5000 m) at high temperatures (>250ºC) for wider utilization of geothermal energy. This will be achieved with a significant increase in the drilling speeds and reduced tripping operations with improved downhole tool lives and reliability. Some of the proposed drilling technologies include a bi-stable fluid-driven mud hammer, low-cost 3D printed sensors and cables, monitoring systems, graphene-based materials, and coatings. The foreseen impact of the project will speed up drilling of the production and injection wells, especially for geothermal power generation. It will also allow expanding the use of geothermal energy sources, simultaneously significantly lowering the environmental impact and reducing the capital expenditure (CAPEX) and allowing for larger cost savings.
Fig. 1. An example of the water-powered down-the-hole (DTH) percussion hammer (source: http://www.adconstruction.com.pl/)
Technologies developed during Geo-Drill project will be subjected to a full-scale laboratory testing under realistic reservoir conditions using i.BOGS (in-situ Borehole and Geofluid Simulator) by International Geothermal Centre (GZB) in Bochum and will be tested using the industrial drilling rig. I.BOGS will allow simulating quasi scale-preserving processes at reservoir conditions up to depths of 5000 m and represents a large-scale pressure vessel for iso-/hydrostatic and pore pressures up to 125 MPa and temperatures from –10°C to 180°C. The in-situ test site at GZB is located on the campus of the Bochum University of Applied Sciences.
Fig. 2. Drilling site at the International Geothermal Centre (GZB) in Bochum (source: Umwelt NRW – Land NRW)
The project kicked-off on the 3rd of April this year with a consortium meeting hosted by TWI Ltd. and will run for 42 months. The Geo-Drill consortium includes product developers and end-user/ geothermal drilling operators ID, an engineering firms, universities, and research institutes such as TWI Limited (Coordinator, UK), Bochum University of Applied Sciences (Germany), Geolorn Limited (UK), Jardboranir HF (Iceland), Precision Varionic International Limited (UK), Technovative Solutions Ltd (UK), Flowphys AS (Norway), Commissariat A. L. Energie Atomique et Aux Energies Alternatives (France), Gerosion EHF (Iceland), Haskoli Islands (Iceland), Rina Consulting – Centro Sviluppo Materiali SPA (Italy) and Graphenea SA (Spain).
This wraps up our #GeothermalFactsandStats blog update on the Geo-Drill project in Bochum. Please check back weekly for new blog posts and follow us on all major social media platforms.
Author: Michal Kruszewski