Evaluation of solar hot water heating system applications to high-rise multi-family housing complex based on three years of system operation

Abstract This study evaluated three-year operation of solar hot water heating system installed in multi-family housing complex with 1179 households in 14 units. At first, since the size of systems for multi-families are large, position of the building services room and collector installation becomes a significant matter. In order to resolve this, three building services rooms for three or four units of households were planned and the solar collectors were integrated directly on the roof facing South at 22° degrees to the horizontal. The accumulated heat gain from three-year operation was 52% of the design baseline (4069 GJ/year). The reason for this could be a low altitude angle of collectors from the architectural design. Moreover, hot water usage and breakdowns of the system were evaluated using detailed analyses of operation data for three years by considering seasonal factors. These results are expected to give valuable feedback for the future design and wide use of the systems, as well as update the design baseline. Lastly, compared to a conventional boiler(δ = 85%), the system produced a positive environmental effect equivalent to a reduction in oil use of 71,907 L/year, and reduced carbon emissions equivalent to 50.8 TC and 186.3 TCO2 the pay-back period for the system was expanded 5 years.