Despite years of experience with geothermal systems, the geothermal sector still faces a significant number of underperforming doublets, posing a strong limitation on a region’s growth of geothermal energy utilization. A key operational challenge in geothermal energy production is restricted flow. Major obstacles for geothermal flow are scaling (mineral deposition), clogging (solid micro-particle deposition), corrosion and inefficient injection strategies. These issues result in high and mostly unforeseen costs for workovers, and additionally reduce production. In order to overcome these challenges, the consolidation and sharing of knowledge, including validated strategies for prevention and mitigation needs to be in place.
Therefore a consortium consisting of De Nationale Geologiske Undersøgelser for Danmark og Grønland (GEUS) and FORCE Technology from Denmark, Helmholtz Centre Potsdam German Research Centre for Geosciences (GFZ) and Hydroisotop GmbH from Germany and Ammerlaan Geothermie B.V., Greenwell Westland B.V., Wageningen Food & Biobased Research and ECN part of TNO from the Netherlands proposed a GEOTHERMICA project PERFORM, which has been granted. The overarching target of PERFORM is to improve geothermal system performance, lower operational expenses and extend the life-time of infrastructure by the concept of combining data collection, predictive modelling, innovative technology development and in-situ validation. The improvement of geothermal plant performance from the proposed work is expected to result in an increase of the energy output by 10 to 50%. In order to reach this goal PERFORM will establish a single and shared knowledge database, build predictive models and demonstrate new and improved, cost-effective technologies which will reduce or even eliminate flow-obstructive scaling, clogging, and resistance to fluid (re-)injection at eight geothermal plants across Europe.
Based on experiences from operating geothermal sites within the EU, PERFORM will establish a single knowledge database containing information on operational, chemical and physical aspects of geothermal energy production. The database enables sharing experiences from operating geothermal doublets located in various countries and comparing the performance of the different geothermal reservoirs.
PERFORM builds predictive models that allow for pinpointing the most likely sources and causes of failure, as well as the best options for injectivity improvement. The integrated models will provide forecasting for scaling, productivity, and injectivity on short- and long- time scales, supporting early warning and planning of mitigation measures. Coupled thermo-hydro-mechanical-chemical simulators will allow for evaluation of injection temperature that apart for increasing flow will also increase the energy output.
Data and knowledge gathering and technology demonstration is planned for eight geothermal plants across Europe. Demonstration of new and improved, cost-effective technologies will allow for the reduction or even elimination of flow-obstructive scaling, clogging, and resistance to fluid (re-)injection. The technologies include low-cost cation extraction filters, self-cleaning particle removal appliances, H2S removal technology and soft-stimulating injection procedures (thermal and CO2-injection). The goal is to provide a set of new and improved, low-cost and environmentally friendly technology alternatives.
PERFORM integrates the knowledge database, predictive modelling and advanced technologies into a design and operation toolbox, which will be tied to economical calculations. The toolbox will enable stakeholders and specifically geothermal operators to plan future operations, mitigate existing obstructions, and optimise production/injection procedures, thus ensuring maximum energy production when needed.
This project has been subsidized through the ERANET Cofund GEOTHERMICA (Project no. 731117), from the European Commission, Topsector Energy subsidy from the Ministry of Economic Affairs of the Netherlands, Federal Ministry for Economic Affairs and Energy of Germany and EUDP.