Comparison and optimization of building energy supply systems through exergy analysis and its perspectives

Growing concerns on environmental problems related to current energy use have emphasized the importance of "energy-saving measures" and the necessity for an increased efficiency in all forms of energy utilization. Being responsible for around 40% of the final energy use in Germany, buildings are major contributors to energy related problems and a sector where a more rational and efficient energy use is absolutely necessary. By showing the thermodynamic efficiency of an energy system, exergy analysis is expected to be a valuable tool for developing and designing more efficient energy supply systems in buildings, similarly as it has contributed to raise the efficiency of power plants. In this thesis, the usability and added value of exergy analysis applied to different building energy systems is investigated. Exergy analysis is, herefore, compared to conventional primary energy assessment and the different results and conclusions obtained from both methods are thoroughly studied and discussed.