Ground source heat pumps (GSHP) are a common technology to provide heating and cooling for both commercial and residential buildings. The ground is attractive as a sink or source of heat because of its relatively stable and constant temperature. The heat is exchanged by circulating a secondary fluid (or groundwater) throught a closed (or opened) loop in the ground. Heat or cold extracted from the ground is delivered (often through a heat pump) to the building. Our research is focused on finding answers to improve the current design methods and to characterize the thermal processes inside borehole heat exchangers (BHEs) and in the surrounding ground. We are a relatively young group and we have great motivation to promote this technology!
Research activities in GSHP systems at KTH were started by Palne Mogensen in 1983. Palne was pioneer on the studies about Thermal Response Test (TRT). At the same time, a significant amount of research was carried out on heat pumps at the Department of Energy Technology under the leadership of Prof. Eric Granryd.
Research activities specifically on heat exchange with the ground were restarted again in 2006 by Prof. Björn Palm and José Acuña at the Energy Technology Department, resulting in suggestions for improvements of BHEs. José picked also up Palne's studies and took TRT further during his Master and Ph.D. studies. José utilized the Distributed Temperature Sensing (DTS) technique in borehole heat exchangers and developed the so-called Distributed Thermal Response Test (DTRT).
In 2010, José supervised Patricia Monzó during her MScThesis. Currently, Patricia is carrying out her Ph.D studies on modelling the thermal process of multi bore field. Patricia has developed a novel numerical model that allows describing in detail the thermal process in the ground. Almost at the same time, Alberto Lazzarotto started his Ph.D studies at the Civil Engineering Department (KTH), in 2009. His Ph.D project focused on developing semi-analytical models for a detailed analysis of large bore field systems. Alberto finished his Ph.D in 2015 and continued his research activity at the Department of Energy Technology.
Monika Ignatowicz started her Ph.D studies in 2011 at the Department of Energy Technology. Monika's Ph.D studies are about the thermophysical properties of secondary fluids used for different indirect refrigeration systems and GSHP systems. Secondary fluids are water based solutions of alcohols, glycols or salts having a low freezing point and her research is focusing mostly on search for the alternative fluids as well as improving the existing ones in terms of different properties and corrosiveness.
At the beginning of 2016 Willem Mazzotti and Mohammad Abuasbeh enrolled in their Ph.D studies at the Department of Energy Technology. Willem's Ph.D studies focus on deep and coaxial BHEs for GSHP application. Throughout his Ph.D, Willem will experimentally investigate thermal and hydraulic performance of these kinds of systems, as well as analyze them from a techno-economic perspective. One of the aims is to find out the advantages and drawbacks of such systems. Part of Willem's work will also be dedicated to modelling and construction of a lab-scale model of the ground. Mohammad is carrying out his Ph.D studies in the field of aquifer thermal energy storage.
Our Sponsor and Partners
Our projects have been mainly financed by the Swedish Energy Agency, Formas, Vinnova, and more than 50 industrial partners.