Efficiency and reliability of energy systems in urban districts with seasonal energy storage in aquifers (Aquifer Thermal Energy Storage ATES Berlin)
The use of aquifers for storage of thermal energy implies a use of both the thermal storage capacity of ground water as well as that of the water-saturated rock. Both heat and cold can be stored. The storage capacity of an aquifer is large compared to other thermal storage systems due its large mass. For this reason, aquifers are often used for seasonal or long-term energy storage.
Geothermal Technologies: continuous microgravity monitoring for integrated mass and stress balance analysis in a volcanic geothermal field - contribution for exploitation sustainability in Indonesia and Iceland - MikroGraviMoTiS
Mass distribution changes are monitored by simultaneous measurements of spatially distributed high-performance, high-frequency gravitymeters in an operated geothermal field, to better understand the related reservoir processes.
Fracture-dominated development of a deep geothermal reservoir for electricity generation in the North-German Basin – Seismic exploration, concept and well planning at the Groß Schönebeck site – RissDom-A
Further investigations at the Geothermal Research Platform Groß Schönebeck are carried out in order to show, if the geothermal potential of the North-German Basin (NGB) can be utilized for electricity generation with a fracture-dominated development of the deep geothermal reservoir in the Rotliegend.
CO2 post-injection monitoring and post-closure phase at the Ketzin pilot site
Since 2004, research on the storage of CO2 in a deep saline aquifer is being conducted at the Ketzin pilot site in Brandenburg. The CO2 injection was successfully carried out between June 2008 and August 2013 and accompanied by one of the world's most extensive monitoring programs.
The project aims to optimize the energetic use of biomass and to enhance its sustainability. It focuses on
further development of biogas technology in variety of substrates and process control
ecological and economic evaluation of the enhanced technologies.
The framework for the use of biogenic residues needs to be improved. The profit of a biogas plant increases by the efficiency of the technology. In this context early warning systems in terms of process failures will be developed. They will allow the use of a variable substrate mix and provide a high performance operation.
The relevancy of alternative energy resources is still increasing because of limited fossil fuels and the negative effects of climate change due to the accumulation of CO2 in the atmosphere. Therefore the utilization of subsurface stored energy arouses increasing interest of scientists. The research project AquiScreen investigates the operational reliability of geothermal used groundwater systems under microbial, geochemical, mineralogical, and petrologic aspects. The screening on the 8 different geothermal systems aims to identify the decisive parameters for the monitoring.
The main emphasis is placed on the characterisation of the underground processes, including physico-chemical reactions as well as microbial reactions between gas (either dissolved in water or in the supercritical state), fluid, and the mineral content of the reservoir rock and the cap rock. In order to investigate processes in the deep biosphere that will occur between injected CO2, the rock substrate and the microorganisms, the PCR SSCP method (PCR–Single-Strand-Conformation Polymorphism-Based Genetic Profiles of Small-Subunit rRNA Genes) is used.
Co-digestion is a four stage process. Organic waste and sewage sludge or renewable primary products and manure are degraded by microorganisms to methane and carbon dioxide. There are two profits: The digested sludge is a valuable fertilizer or soil conditioner and the gas generates renewable energy.
Advanced process understanding of engineered geothermal systems is a prerequisite to optimize plant reliability and economy. In the frame of the MiProTherm project microbial, geochemical and mineralogical aspects of geothermal groundwater systems are investigated. While the main focus of the project is on characterisation of indigenous microbial communities and changes of their activity due to plant operation, the monitoring of geochemical and biogeochemical parameters also allows for process analysis.
The Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) "Marktanreizprogramm" program for renewable energies is an essential supporting measure for market penetration of renewable energies in the heat sector. The "Marktanreizprogramm" is being continuously scientifically evaluated in order to monitor the effects of measures.
On behalf of BMU, the evaluation period 2009-2011 is coordinated by Fichtner. GFZ is working within this project in the field of deep geothermal plants.
The contribution of geothermal energy is a key factor to the successful achievement of the objectives of the European Commission concerning the development of renewable and sustainable energy. The concept of Unconventional Geothermal Resources and in particular Enhanced Geothermal Systems examines ways of increasing the potential of geothermal power generation through (i) exploring new types of reservoirs for heat exchange (Hot Dry Rock, supercritical fluids..), (ii) enlarging the extent of productive geothermal fields by stimulating permeability, (iii) enhancing the viability of current and potential hydrothermal areas by stimulation technology and improving thermodynamic cycles.
The European HITI project aims to provide geophysical and geochemical sensors and methods to evaluate deep geothermal wells up to supercritical conditions (T>380°C). Supercritical geothermal wells are presently non-conventional but may provide a very efficient way to produce electricity from a clean, renewable source.
The Rotliegend of the North German basin is the target reservoir of an interdisciplinary investigation program to develop a technology for the generation of geothermal electricity from low-enthalpy reservoirs. An in-situ downhole laboratory was established in the 4,3 km deep well Groß Schönebeck with the purpose of developing appropriate stimulation methods to increase permeability of deep aquifers by enhancing or creating econdary porosity and flow paths. The goal is to learn how to enhance the inflow performance of a well from a variety of rock types in low permeable geothermal reservoirs.
The LOW-BIN project aims in improving cost-effectiveness, competitiveness and market penetration of geothermal electricity generation schemes, targeting both hydrothermal resources for immediate market penetration and future hot dry rock systems, by:
- Widening market perspectives of geothermal Rankine Cycle power generation by developing a unit that can generate electricity from low temperature geothermal resources, with temperature threshold for profitable operation at 65 °C , compared with 90-100 ° C of existing units.
- Developing a Rankine Cycle machine for cogeneration of heat and power by heat recovery from the cooling water circuit.
The project I-GET is aimed at developing an innovative geothermal exploration approach based on advanced geophysical methods. The objective is to improve the detection, prior to drilling, of fluid bearing zones in naturally and/or artificially fractured geothermal reservoirs. This new approach will be tested in four European geothermal systems with different geological and thermodynamic reservoir characteristics: two high enthalpy (metamorphic and volcanic rocks), one middle enthalpy geothermal system (deep sedimentary rocks), and one low enthalpy geothermal system (shallow sedimentary rocks).
The northwestern Great Basin (NGB) in the western USA hosts abundant, generally amagmatic geothermal activity. Significant geothermal exploration is ongoing, but controls on fluid flow in the geothermal systems are generally poorly understood. In collaboration with the UNR, we will contribute to the characterization of fractured reservoir rocks in order to understand the structural controls on fluid flow.
Sustainability concepts for exploitation of geothermal reservoirs in Indonesia – capacity building and methodologies for site deployment - Indonesia
The collaboration in methodology and technology development in combination with a training program will support capacity building in geothermal technologies in Indonesia.
The goal of the subproject conducted by the International Centre for Geothermal Research (IGC) at the German Research Centre for Geosciences is the determination of the stability and efficiency of the inhibitors at reservoir-like conditions. Additionally, the degradation pattern of the inhibitors in natural and synthetic fluids will be characterized.
Experiences from existing geothermal plants and projects show that energy provision from deep geothermal reservoirs is feasible in Germany at various locations. However, it is evident that there still exist numerous challenges regarding planning and operation of plants. The next step for further geothermal development, therefore, is to improve the quality and confidence of both the planning process and operation as well as the competitiveness of geothermal installations.
Within in the scope of the joint project BRINE the synergetic utilisation of CO2 storage and geothermal heat production of a saline aquifer in Eastern Brandenburg was investigated. One of the main objectives was to design an integrated geophysical monitoring system, consisting of geoelectrics, electromagnetics and magnetotellurics, to observe possible saltwater migration within the reservoir.
The goals of the collaborative research and development project CLEAN (CO2 Large-Scale Enhanced Gas Recovery in the Altmark Natural Gas Field) are to research opportunities for the mobilization of natural gas volumes that are not conventionally extractable and to increase knowledge about the geological storage of CO2 in nearly exhausted natural gas fields.
The CO2SINK (CO2 Storage by Injection into a Natural saline aquifer at Ketzin) integrated project aims to advance the understanding of the science and practical processes involved in underground storage of CO2 to reduce emissions of greenhouse gases to the atmosphere. The consortium running this EU project consists of 18 partners from universities, research institutes and industry out of 9 European countries.
The planned increase of solar and aeolic within the german energy mix is confronted with large fluctuations in electricity production due to fluctuating saisonal and metereological conditions. A boost of electricity networks' capacity, as well as of the technology for conversion and storage of excess electricity is therefore extremely important. Given the current german energy mix, which is mainly sustained by electrification of fossil fuels and controlled nuclear fission, the storage of large amounts of energy has not been a relevant issue.
Application of diffuse degassing measurements to map permeable fault structures across geothermal systems
The objective of this project in New Zealand is to improve fault zone analysis for the exploration of geothermal systems. It combines two technical approaches of diffuse degassing and emanation measurements at the Earth’s surface.