Economic analysis of conventional single slope solar distillation plant for different climates in India

Abstract

The solar distillation system offers a sustainable tool for freshwater production. However, the lower production output is one of the barriers to the non-commercialization of solar distillation systems. Although for small-scale production, solar distillation is still considered to be an economical and reliable option. To test the viability and affordability of a solar distillation system, techno-economic investigation of a single slope small-scale distillation plant of capacity 100–400 L/day has been conducted for three different climates in India viz. hot and dry, hot and humid, and composite. Annual distillate output is numerically computed for three different cities corresponding to respective climatic zones. The average and maximum evaporation area of still required to fulfill the requirement for drinking water is computed. It is seen that the climate of Chennai has a maximum annual yield of 1319.6 L/m2, whereas the composite climate of Delhi has a minimum yield of 1120.4 L/m2. The yearly distillate of Jodhpur's climate is 1164.6 L/m2. Water cost is computed in terms of water produced in liters (cost/L) and energy output from solar still (cost/kW h). It is seen that the cost/L and cost/kW h of water produced for the different climatic zone in India is in between Rs. 0.73/L to Rs. 0.87/L (0.010USD/L to 0.012USD/L) and Rs 1.13/kW h to Rs 1.33/kW h (0.016USD/L to 0.019USD/L). Payback time to recover the distillation plant's investment cost for different climates is between 99 days and 116 days. (1USD = Rs70/–).