Experimental investigation and economic analysis on a solar pure water and hot water hybrid system

Abstract

• Solar pure water and hot water co-production equipment was fabricated and tested. • Exergy and economic analyses of the pure water and the overall system are made. • The pure water and hot water daily production could meet the needs of household. • The pure water index could completely reach the standard of drinking water. In this paper, the present study focuses on innovative design, fabrication, and testing of a solar pure water and hot water hybrid system using a superconducting gas double evacuated tube and heat storage device to achieve a better performance. Exergy analyses of system was made, meanwhile, coefficient of performance and gained output ratio and economic properties has been investigated using data obtained from experimental study of different heat storage temperatures (50 to 70 °C) and without storage during one year under the climate conditions of Jinan, China. The results showed that the system performance had a close relationship with heat storage temperature, first rose and then declined with increasing the heat storage temperature. The method of storage heat and the temperature of the heat storage tank are the key regulatory selections, which allow to give priority to pure water or hot water production according to the ordered demands. The pure water and the hot water for 45 °C production rate of this system were not less than 10138.7 ml/day and 386 kg/day on a sunny day, which could meet the needs of general household drinking water and domestic hot water. The water quality results revealed that, all the samples were well agreed with standard values after distillation. Estimated cost of pure water and hot water in the system is 0.4523¥/L/m 2 and 0.0134¥/L/m 2 respectively.