Abstract
The need to reduce energy consumption (EC) in the building sector in Saudi Arabia, exclusively on hot days, is a concern of many scholars. In this study, the EC of a conference hall in Riyadh was examined with a schedule of attendance from 8 a.m. to 12 p.m. With the introduction of the installing economizer and heat recovery devices, a program was developed so that the active and inactive times change according to the mechanical ventilation schedule. In the first technique, through developing a program on the air change (ACH) parameter, the injection of cool air into the indoor space in the summer was set in the range of 3–12 (i.e., ACH = 3, 6, 9 and 12). The results expressed that the economizer efficacy was more noticeable at a lower ACH value. With a further increase in ACH, although economizer still had a positive effect on reducing EC, the efficacy was less than expected. At best, EC declined by 3.07%. In the second technique, a program was set up that limited the possibility of using heat recovery to the temperature difference between inside and outside. Applying this technique reduced EC by 95% in winter and 34% in summer. But due to the high share of cooling load, annual EC decline was limited to 35%.In the third technique, HS29 phase change material (PCM) was added to the building and it was observed that this material does not have an upright performance on some winter days, but in contrast, it had a very virtuous performance in summer. This method eventually reduced annual EC by 5.6%.
•Building related energy consumption focusing via three techniques•A trade-off between energy consumption and absorbed energy•Installing an air change system by using the HS29 phase change material