New passive thermal comfort system using three renewable energies: Wind catcher, solar chimney and earth to air heat exchanger integrated toreal-scaletest room in arid region (Experimental study)

Thermal comfort is one of the ancient-new challenges of the arid region population and responsible for more than 40% of energy end-use. Renewable energy can be a solution to this problem. In the present paper, the potential of renewable energies to ameliorate thermal comfort and reducing energy consumption in building sectors is experimentally investigated. Three renewable-based applications are used: wind-catcher (WC), solar chimney (SC), and earth to air heat exchanger (EAHE). The three techniques are connected to a real-scale test room and investigated using in-situ measurement. The contribution of each technique is discussed separately. Temperature, humidity sensors, and anemometer are used to study parameters affecting thermal comfort. Obtained results show that the use of wind-catcher could provide in the presence of wind an internal airflow of 3.8 m.s(-1)which reduces inside room temperature by 6 degrees C. A solar chimney creates a difference between its inlet and outlet air temperature by 5.9 degrees C and increases the kinetic energy of hot air leaving the solar chimney which is replaced by cool air from outside and other devices outlet (EAHE and WC) and increases internal airflow even with the absence of winds. The earth to air heat exchanger increases the outlet air temperature in winter by 8 degrees C and reduces it by 12 degrees C in summer. Inside test room hygrometry is also ameliorated by the use of EAHE. Analyzing the new system (test room + WC + SC + EAHE) shows an important amelioration of inside thermal comfort. A difference between inside and outside test room temperature is found: reduction of 13 degrees C in summer, and a gain of 10 degrees C in winter. The new system leads to better inside test room thermal comfort conditions and to reduce energy consumption by almost 50%. The present study presents the first experimental investigation of using three renewable energies in the same building to improve thermal comfort. Using real scale room and in-situ measurement gives a realistic idea and results show that green energy could improve the thermal situation and energy saving. This is an original work to motivate building designers, especially in the arid region to use more than one renewable energy to ameliorate thermal comfort in both summer and winter seasons.