Solar thermal energy with molten-salt storage for residential heating application

Heating application is one of the areas in residential building where residents pay a significant part of energy bill. Thermal energy from solar irradiance can be collected by solar thermal collector (STC) and absorbed by heat transfer fluid (HTF) to transport heat to the heat-exchanger and to the load. This paper investigated various solar collectors and considered parabolic trough collector (PTC) to develop a residential heating application. The system structure mainly consists three subsystems: solar thermal absorption subsystem, thermal energy storage subsystem and underfloor heating subsystem. Because of temperature range and specific heat capacity Nitrate salt (0.54KNO3+0.46NaNO3) was considered in the model. A typical house in Melbourne with heating area of approximately 240m² is considered as thermal load. Model was evaluated for summer, winter and yearly load demand and result showed that molten-salt storage helped the system to operate consistently even at night-time (19:00 - 05:00) without solar radiation.