Nove metody hospodarrneho dimenzovany systemu s tepelnym cerpadlem a svislymi zemnimi vrty = New methods for optimized system design of heat pumps with borehole heat exchangers

The aim of this thesis is to optimize heat pump systems with borehole heat exchanger in terms of energy consumption. The research is dealing with different configurations of system and suitable control strategy. In regards to a great number of system configurations, only four basic of them were selected for the first study. Heat pumps are devices with a dynamic behavior during heating season hence a mathematical simulation describing whole season is used. Simulation is performed for the heating season because in this period gradual changes both temperatures in the surrounding ground and in building heating demand as well appear. Simulation step is set to 3 minutes in order to catch influences of heat storing and rejecting process in the storage tank, as well as of control strategy and borehole local changes in the ground surrounding. Model is compiled in transient systems simulation environment TRNSYS (Transient System Simulation Program). Model calibration is carried out with data measured on real system at CTU in Prague used for heating of a part of laboratory of Department of environmental engineering. System configuration consists of 100 m borehole with double U-tube configuration, 9,6 kW (B0/W35) brine-to-water heat pump, storage tank 540 l, circulating pumps and involved control. Measurement is continuous, every one minute all measuring values are logged with data acquisition equipment and consequentially downloaded to the computer. During calibration is component describing building behavior replaced with real heating capacity measured on the device described above. Meteorological data and technical room temperature are replaced with real measured values. Results of simulation were obtained for simplified building and weather data were used from databases of Meteonorm. The objective is to determine the most suitable configuration with a relevant control strategy. Factor HSPF (Heating Seasonal Performance Factor) was used for comparison of different configuration.