Characterization and Temperature Measurement Techniques of Energy Wells for Heat Pumps
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Ground source heat pumps are a widely used approach to efficiently heat single family houses. In addition to using the ground as a heat source during the winter, it can be used as heat sink and as a free cooling source during the summer. The most common way to carry out the heat exchange with the ground is with the help of energy collectors (borehole heat exchangers) in vertical wells. The quality of the heat exchange depends on the type of collector and on the flow conditions of the circulating fluid. For a complete understanding of the heat transfer performance, it is necessary to carry out careful temperature measurements at research installations and to do a preliminary characterization of the boreholes. These activities might represent a significant cost saving since the system can be optimized based on their outcome. The characterization consists of determining the type of rock and its thermal properties, the groundwater flow at different depths, and the borehole deviation according to the expected position. A comprehensive study about these characterization actions as well as temperature measurement techniques in boreholes using thermocouples and fiber optic technology are described in this report. Study cases from real installations are also presented to exemplify the characterization and measurement methods.
Place, publisher, year, edition, pages
IdentifiersURN: urn:nbn:se:kth:diva-79496OAI: oai:DiVA.org:kth-79496DiVA: diva2:495572
Subject / course
Master of Science - Sustainable Energy Engineering