Efficient design of geothermal heating systems (completed)
EFFSYS+ is the continuation of the earlier research programs “Alternativa köldmedier”, “Klimat 21″, “eff-sys” and “Effsys2″. Energy efficient, user-friendly and sustainable technology shall be developed and resource efficient solutions shall be detected. The vision of EFFSYS+ is to contribute to the development of Swedish industry into an international front position within the area of refrigeration and heat pump technologies.
Our research activity is focused on "Efficient design of geothermal heating systems and implications of EFFSYS2 results".
The project intends to study and improve the performance on the source side of ground source heat pumps based on earlier results from the EFFSYS2 project, though including new aspects:
- Distributed Thermal Response Test – implications for different collector designs
- Evaluation of technical and practical implications of exchanging existing borehole heat exchangers to new more effective designs
- Evaluation of yet more borehole heat exchanger designs, new geometries, new collector materials, and filling materials
- Evaluation of volumetric flow rate optimization for given local borehole depths and ground temperature profiles.
- Investigation of the possibilities for minimizing antifreeze concentration in the secondary fluid, using water as secondary fluid, and potassium carbonate as secondary fluid
- Evaluation of natural convection, forced convection, and freezing of groundwater filled boreholes
- Development of a control software for ensuring the optimum volumetric flow rate in each borehole heat exchanger at different operating conditions. Implications of this on the system design
- Modeling of heat extraction and fluid dynamics in a U-pipe thermosiphon borehole heat exchanger
- Evaluation of re-charging energy wells
- Investigation of taking advantage of the ground temperature gradient for increased efficiency
- Investigation of variation of thermal conductivity along the depth a some selected places around the country
- Evaluation of different grouting material and its thermal and practical implications
Further information about this EFFSYS+ project can be found in this section. Relevant results are published in conferences and scientific journals, follow this link Publications to access them.