Analysis of underfloor electrical heating system integrated with coconut oil-PCM plates

Abstract

In the present study, coconut oil was used as a new bio-based phase change material (PCM) to be integrated with a quarter-scale insulated prototype of an underfloor heating system and its performance was investigated. Two different cases were studied. In the first case, the PCM was placed in an aluminum container that was positioned above an electrical heater, and the adaptation of the PCM to the floor was investigated. The second case was a control test in the absence of PCM plates. To simulate real severe winter conditions, the prototype was tested in an agricultural refrigerator to ensure constant low ambient temperature. The versatility of the underfloor system with PCM facilitates a reduction in heating load during winter while maintaining residential thermal comfort. An economic study was then conducted based on contemporary electricity shifts to inspect the system’s ability in peak load shifting. The results show that the PCM achieved an increase of 53.7% in the duration of energy transfer across charging and discharging. Furthermore, the use of the bio-PCM facilitated a shift in electricity consumption from peak time to off-peak time, yielding an annual cost reduction of 58.9% when compared with that achieved in the control test.