Experimental analysis of a pond water radiant system using a pond water test rig in a radiant-embedded building

This paper investigates the Integrated Energy Systems (IES) of shallow pond water geothermal energy with a radiant cooling system to reduce the thermal energy in buildings. The research experiment aimed to analyse the effectiveness of inlet water temperature, particularly 20°C, on the building envelope (wall, roof and floor) while operating (a) standalone radiant system, (b) the radiant system supplemented by a ceiling fan and (c) the radiant system supplemented by a Fan Coil Unit (FCU). Two identical building constructions were analysed for system thermal performance; one was a radiant room, while the other was a traditional room. Weather conditions, air parameters, temperatures were measured periodically. Operating the radiant system with FCU showed a decreased operative temperature of 26°C when the standalone radiant system showed 33°C at the end of the reading cycle, which is a huge promising difference. The PMV index value of the Fanger's model, while operating the radiant system with FCU, fluctuated in and around ‘0’ indicating almost neutrality with respect to thermal sensation. Therefore, it demonstrates that the Integrated Energy System is effective in reducing indoor air temperatures inside the radiant embedded building during summer, where the outdoor ambient temperature reaches above 40°C in a tropical region.