Abstract

Solar radiation has a potential use as a source of renewable energy, due to its long useful life and constant emission of radiation, however its main drawback is related with its intermittency and non-constant availability. Thermal energy storage (TES) is a technology that can overcome the previous drawback by storing excess of solar energy and release it when is required. This implies important advantages, such as improving the energy efficiency to achieve savings in the different applications. Phase change materials (PCM) are latent heat storage (LHS) materials with high storage capacity, for their applications in buildings as passive technology, with a thermoregulatory potential that could decrease the amplitude of indoor temperature fluctuation. Therefore, the present study shows the impact in the thermal performance of a lightweight building when phase change materials (PCM) are implemented into the building envelope as passive system to store solar energy during winter in the south of the city of Antofagasta, Chile. This country has a great global horizontal irradiance (GHI), corresponding in Antofagasta about 2750 [kWh/m 2 ], which presents a potential application for solar technologies. The mining area of the country is mainly located in the Antofagasta region, where the workers reside in the lightweight containers similar to those analysed in this study. CooL Ltda designed the construction and implementation of the containers, one with PCM and the other without it, with one window and door towards north. The design and orientation of windows allow solar radiation to enter the containers through the building envelope, which causes PCM charge. In the construction process, five sensors were installed, one in each wall and ceiling. Then, both containers were equipped with Pt-100 sensors in walls, roof, floor and one in the centre for the room temperature. These sensors were connected to a data logger DL01-CPU. The results show that the PCM performs a passive increasing the thermal comfort time inside the construction according comfort conditions (20ºC-25ºC) thanks to the storage capacity of the material, besides not presenting overheating, considering the high temperatures from the north of Chile. These results were analysed during winter (July to September in the southern hemisphere), season in which the high external temperature allows to reach the fusion temperature of PCM. This study experimentally demonstrated the benefits of using passive PCM for purposes.