Energetic, economic, environmental and climatic analysis of a solar combisystem for different consumption usages with PSI method ranking.

Using solar systems is increasing due to oil shortage, environmental effects, and renewability. Solar thermal combisystems use the energy taken to provide for both domestic hot water (DHW) and space heating (SH), which is under investigation by energy researchers. This study uses a dynamic energy analysis of the solar system to evaluate the solar parameters. Also, the environmental and economic effects of using solar systems are discussed. The study is done on four different consumption usages in four different climates of Iran. Energy simulation shows that hot & humid climates, office, and mall usages have the largest solar fraction (minimum of 95.2, 38.5, and 35%, respectively). The lowest optimal collector surface area belongs to a hot and humid climate with 4–21.5 m2 and office usage with 4–159 m2. Also, collector efficiency decreases with higher collector area amounts. 20-year economic analysis shows that the net present value of hospital usage with a maximum of $2216.8, cold climate with a maximum of $768.4, and hot & humid climate with a maximum of $2765.9 are the most affordable. The environmental analysis illustrates that CO2 emission avoidance is highest in hospital usage with a maximum of 1924.5 kg, residential usage with a maximum of 1707.8 kg, and hot & dry climate with a maximum of 1349.2 kg. Lastly, the preference selection index (PSI) method is used to rank all application possibilities, which shows that using systems is highly recommended in cold, hot & humid climates with the best ranks of 1 and 3 and hospital usage with the best rank of 1. • Solar fraction of solar thermal combisystems can reach up to 95% in hot and humid climate. •Collector efficiency is higher in low collector areas. •Economic analysis shows that cold and hot and humid climates are mostly affordable. •Environmental analysis indicates that residential and hospital usages avoids more CO2 emissions. •PSI method of mathematical prioritizing is used to rank choices. [ABSTRACT FROM AUTHOR]