Design and thermal performance assessment of water sink based thermoelectric radiant panel system for office cabinet cooling and heating

As energy efficiency becomes a priority in building spaces, achieving thermal comfort temperatures without excess energy use is essential. Few studies offer a comprehensive analysis combining water-based heat sink integration with thermoelectric radiant panel (TERP) design and actual cooling or heating performance under realistic operating conditions. Therefore, this study investigates a water sink based TERP system that can provide uniform and energy-efficient cooling and heating in small office cabinet under realistic operating conditions. Three TERP units, each with eight thermoelectric modules (TEMs), were installed across three walls in a 1.2 x 1.2 x 2 m office cabinet. In each 0.75 x 0.50 m TERP, TEMs are spaced 0.25 m apart in a triangular arrangement to ensure uniform surface temperature, with a water block acting as a heat sink to maintain the temperature difference across TEM. The 'I' water flow path configuration was used for heat removal, verified through CFD simulations. Results show optimal performance at a 1-2 A input current, with each TEM delivering 3-5 W of cooling capacity. The TERP system reached thermal comfort temperatures within 40 min for cooling and 27 min for heating, achieving a COP of 0.65 at 21.8 V and a maximum COP of 1.14 at 12 V in cooling and heating mode, respectively. These findings demonstrate the TERP system's capability to provide energy-efficient temperature control in small spaces. This study's approach could enhance the TERP system's COP and cooling/heating capacity by using a TEM with a higher figure of merit and other hybrid methods.