Effects of examine the phase change material through applying the solar collectors: exergy analysis of an air handling unit equipped with the heat recovery unit

Abstract Taking into account a share of 42.4% of total energy usage for buildings, utilizing of energy reduction techniques in this sector will be effective. In this article, transient energetic analysis along with the exergetic study of an air handling unit (AHU) equipped with a heat recovery unit (HRU) were examined. The transient analysis was performed in July by developing a program based on the energy/exergy balance equations. The results showed that owing to using the phase change material (PCM), heat exchange diminished by 545 kWh July (8.6% reduction). Owing to using of a heat recovery unit, the cooling load energy demand lowered by 4043 kWh July (10% reduction). Although the irreversibility through the cooling experienced a 20% reduction due to the addition of an HRU, but the total irreversibility decreased by only 0.4%. Integrating the solar system with AHU + HRU led to energy-saving by 1832 kWh (11.6% reduction). Moreover, the total irreversibility reduced by 9% due to using the solar system. Finally, it was found that the solar system accounts for 83.62% of the total irreversibility.