Agile solar roof tile HVAC

Abstract

This paper studies the technical feasibility of a novel solar roof tile (SRT) to be used for HVAC (heating, ventilation and air conditioning) in buildings. The SRT utilizes a phase change material (PCM) for thermal storage. The SRT works like a conventional thermal storage tank while featuring compact size and lower cost. Two heat exchangers are connected one each on the top and bottom of the PCM matrix. The top heat exchanger functions as an absorber of solar heat. Aqueous sodium hydroxide passes to the top heat exchanger from a storage sump. The bottom heat exchanger is the condenser and evaporator with water passing through the heat exchanger. The cooling system is integrated inside the customised roof tile interlocking system. This system uses roof tiles that have higher performance during extreme weather conditions and lower maintenance costs. In this paper, we have investigated the thermal performance and technical feasibility of the proposed solar SRT-HVAC system. This proposition eliminates conventional thermal storage tanks used in solar thermal collectors. The dynamic performance of the SRT under transient conditions is evaluated using the TRNSYS modelling package, which shows the influence of design variables like insulation points and charging/discharging durations on thermal storage performance.