Thermal and energy performance evaluation of a dry floor heating system based on hybrid heat storage aggregates for field application

Abstract

The application of thermal energy storage (TES) systems in buildings has increased with growing interest in renewable energy technology. TES systems that use phase change materials (PCMs) are preferred over other energy storage methods. This study produced an activated carbon (AC)-based shape-stabilized PCM (ACS-PCM) using AC and n-eicosane, which was injected into a polyvinyl chloride (PVC) container to manufacture a heat storage container. The thermal properties of the ACS-PCM were analyzed to evaluate its performance when the manufactured heat storage container was applied to a dry floor heating system. Because of its high thermal conductivity, the ACS-PCM was superior to n-eicosane in heat transfer when heated. Moreover, the ACS-PCM exhibited a time-lag effect owing to heat storage during heating and free cooling. The PCM dry floor heating system consumed 77.3 % of the energy of the wet floor heating system. Finally, to increase the heat transfer efficiency, the ACS-PCM and pure n-eicosane were simultaneously injected into the PCM container to fill the gap between them; however, there was a temperature difference, highlighting the need for improved thermal conductivity of PCM container materials.