Exergetic, economic and environmental (3E) analysis of a low cost solar heater in different configurations

This study is the first report in the literature of exergetic, economic, and environmental (3E) analysis for low cost solar heaters (LCSH). In this context, 3E analyses were performed for two LCSH configurations, tubes of the absorber plate connected in series and parallel. The mean exergy efficiency of the LCSH in parallel was 2.56% while for the LCSH in series it was 2.01%. The parallel collector presented lower rates of exergetic destruction and entropy generation, besides a higher overall efficiency. The use of alternative materials in the construction of the LCSH made it possible to achieve low values of embodied energy and embodied carbon emission and consequently excellent environmental indicators. It was found that the simple payback period (SPP) and the leveled heating cost (LCOH) found were 0.38 years and 0.014 US$ kWh−1 for the collector in parallel and 0.42 years and 0.016 US$ kWh−1 for the collector in series. Based on the analyses performed, the LCSH in parallel proved to be the most attractive alternative among the evaluated ones and is indicated for operations where high efficiencies and high temperatures are not required and the cost factor is important.