Options
2009
Conference Paper
Titel
Exergy analysis of different domestic hot water hydraulic configurations
Abstract
Exergy analysis has been widely used for the optimization and allocation of losses in power production energy systems. Similarly, it can be applied to the optimization of energy processes in buildings. Exergy demands for heating, cooling and domestic hot water production for buildings are low due to the low temperature levels required to supply these needs. Thus, lowering the supply temperature for these applications is in principle advisable. Yet lower supply temperatures come along with higher mass flows and, subsequently, higher pumping power is required. In energy terms, thermal and electrical energy flows are equivalent. In turn, exergy analysis allows an evaluation of these energy flows based on their potential to deliver work, thus increasing the importance and losses derived from pumping energy to supply the thermal demand. This paper focuses on the domestic hot water production (DHW) system. Several hydraulic configurations for the DHW supply of a multi-family dwelling are investigated and analyzed from an exergy perspective. Results show the allocation of the energy and exergy losses in the several components of the energy supply system. The exergy efficiency and total energy demand of the systems presented will be compared to derive the more optimum hydraulic configuration.