Commercial and residential buildings consume 20% of the world's total energy usage and forecasts indicate a growing trend of 1.5% per year by 2040. Share of energy consumption in the heating ventilation and air conditioning (HVAC) reached to 40–70% of the building energy usage. Reduction in the heat exchange between the interior and exterior spaces is an energy-efficient technique for lowering HVAC energy demand. In this study, the thermal performance of a PCM-based wall was numerically examined in the winter. The main purpose of this research was to investigate the efficacy of installing PCM inside the envelope on reducing heat loss from the conditioned space and at the same time its effect on air handling unit (AHU) energy usage. For this, seven different PCM layers at melting temperatures of 276.15–293.15 K with a thickness of 1 cm were loaded into the envelope. Based on the results, among the PCMs thermophysical properties, thermal conductivity has more manifest efficacy. Under the best conditions, owing to installing PCM of A3 inside the envelope, the energy-saving in December, January and February diminished by 11.25%, 11.23% and 10.35%, respectively. Also, thermodynamic calculations affirmed that the maximum reduction in AHU power usage owing to PCM loading was 11.73%. Using payback time technique, the economic analysis was performed and it was found that under the best conditions, the payback time is 18.6 years.

商业和住宅建筑消耗了全球能源总使用量的20％，并且预测表明，到2040年，这一趋势将以每年1.5％的速度增长。在采暖通风和空调（HVAC）中，能源消耗的份额达到了建筑物的40-70％能源消耗。减少内部和外部空间之间的热交换是降低HVAC能源需求的节能技术。在这项研究中，在冬季以数字方式检查了基于PCM的墙的热性能。这项研究的主要目的是研究在外壳内安装PCM的功效，以减少调节空间产生的热量损失，同时降低其对空气处理单元（AHU）能耗的影响。为此，熔化温度为276.15–293的七个不同的PCM层。将厚度为1 cm的15 K装入信封。根据该结果，在PCM的热物理性质中，导热率具有更明显的功效。在最佳条件下，由于在外壳内安装了A3的PCM，因此12月，1月和2月的节能量分别减少了11.25％，11.23％和10.35％。此外，热力学计算结果表明，由于PCM负载，AHU功耗的最大降低为11.73％。使用投资回收期技术进行了经济分析，发现在最佳条件下，投资回收期为18.6年。12月，1月和2月的节能量分别减少了11.25％，11.23％和10.35％。此外，热力学计算结果表明，由于PCM负载，AHU功耗的最大降低为11.73％。使用投资回收期技术进行了经济分析，发现在最佳条件下，投资回收期为18.6年。12月，1月和2月的节能量分别减少了11.25％，11.23％和10.35％。此外，热力学计算结果表明，由于PCM负载，AHU功耗的最大降低为11.73％。使用投资回收期技术进行了经济分析，发现在最佳条件下，投资回收期为18.6年。