Thermal performance of bio-based phase change material encapsulated in a bamboo wall for residential buildings: A field experiment

Despite Indonesia's abundant resources for coconut oil-based phase change material (CO-PCM), there are limited studies on how the PCM performs in highland areas of tropical countries. This study explores the potential of CO-PCM encapsulated in bamboo for effective thermal stabilisation. Field experiments were conducted by comparing two identical rooms with a total area of 57.6 m² enveloped with bamboo panels: Room 1 had bamboo panels filled with CO-PCM, and Room 0 had air-filled bamboo panels serving as a reference. Temperature variations were observed for two consecutive 24 h cycles in Ciawi, Indonesia, using thermocouples placed inside and on the surface of the panels. The temperature analysis was categorised into four periods to understand thermal performance at different times. Results demonstrate that CO-PCM inside the bamboo panels can reduce the temperature peak to around 1 °C and maintain the indoor temperature of approximately 1 °C during the diurnal and nocturnal periods, respectively. Moreover, the room with CO-PCM shows a more stable mean ambient temperature than the reference room. This study also highlights that the west-side panels release more heat than the east's due to their exposure to the more intense afternoon sun. The CO-PCM shows its performance by optimally lowering the temperature during the daytime and increasing the temperature at nighttime. These findings showed that bio-based PCM encapsulated in the bamboo wall in highland areas' housing is able to stabilise indoor temperature.