The impact of ETC/PCM solar energy storage on the energy performance of a building

Abstract

The main goal of this investigation was to increase the solar fraction and reduce the demand for non-renewable primary energy in a building heating system. Thermal performance of the prototype evacuated tube solar collector/storage integrated with a PCM (ETC/PCM) was analyzed. Technical grade paraffin with onset melting point of 51.24°C was used as a PCM. It has been shown that the highest solar energy fraction in the building heating system was obtained with a thermal load of 40 W·m-2 and the highest the surface area of ETC/PCM aperture in relation to the heating surface area value of 0.2. Lowering the heating system parameters from 45/35°C to 35/25°C allowed for an increase in heat output from solar energy in the range from 2.71% to 5.44%. The largest increase in the solar fraction was in the range of the ratio of the surface area of the solar collector ETC/PCM aperture to the area of the heated building from 0.03 to 0.07. In summary, obtained results indicated that the proposed solution allowed reduction of non-renewable primary energy demand in conceptual heating system from 6% to 27% depending on the heat load of the building and the aperture area of the ETC/PCM.