In situ latent thermal energy storage in underfloor heating system of building connected to the parabolic trough solar collector-an experimental study

High energy demand, and excessive consumption of natural resources, have become one of the most critical global challenges. The building sector is one of the most energy consumers, and it almost consumes one-third of final energy worldwide. Hence, it is one of the most significant CO2 emission sectors. Utilization the renewable energy in building such as solar energy connected with latent thermal energy storage (LTES) using phase change materials (PCM) is a promising solution to reduce conventional energy consumption and diminish greenhouse gas emissions. Separately, a proper heating system selection preparing a comfortable heating condition is a priority. Underfloor heating systems (UFHSs) can maintain indoor air temperature more comfortably than other heating systems. This study used parabolic trough solar collector (PTSC) as a heating source for two test cubicles equipped with underfloor heating systems. In situ latent energy storage using hydrate salt with 32 degrees C melting temperature is used in one test cubicle and it compared with the typical underfloor heating system embedding pipes under sand in the other same cubicle. Results revealed that the latent thermal energy stored in PCM can maintain the indoor air temperature of the cubicle in comfortable condition for more than 4 h after sunset. Furthermore, PTSC provides more than 80% of cubicles heating loads during the coldest time in Tehran, Iran.