Application of Solar Thermal Collectors to Improve the Energy Performance of the Fresh Air HVAC Systems

 In the preset study, the performance of a solar assisted heating, ventilation and air conditioning (HVAC) system in an operating theater building was studied. The yearly performances of the existing HVAC system and the system with the added solar collectors were simulated in terms of energy consumption and provided air conditions using a transient system simulation software (TRNSYS). In the modified system, the solar collectors feed a liquid-to-air heat exchanger, which was defined to be replaced with the main heater of the HVAC system during the day times throughout the year. Three solar integrated HVAC system configurations consisting of three types of standard liquid flat-plate collectors namely, Configuration A: unglazed, Configuration B: glazed painted, and Configuration C: evacuated tube solar collectors were examined to determine the most proper configuration in terms of energy consumption and provided air conditions. Based on the simulation results, all the configurations examined were capable of providing proper air into the space. However, the energy performance of the configurations indicated that the Configuration A has priority in terms of energy consumption level and was recommended to be implemented in the existing HVAC system.