Multi-objective optimization of the hybrid photovoltaic-battery-diesel-desalination system based on multi-type of desalination unit.

Meeting the energy and water demands of remote areas has created significant challenges globally. To address this issue, the utilization of hybrid energy-water systems, integrated with renewable energies, has been highlighted as a viable solution. This work has been focused on the multi-objective optimization of a hybrid energy system, encompassing photovoltaic panels, batteries, diesel generators, and desalination units. The design goals to achieve the optimal configuration include minimizing system costs, reducing carbon dioxide emissions, enhancing the renewable factor, and improving reliability. Also, for the mentioned design goals, the performance of three desalination methods including reverse osmosis (RO), multi-stage flash (MSF), and multiple-effect distillation (MED) was evaluated by Hybrid Optimization of Multiple Energy Resources (HOMER) software. Our findings reveal that the RO desalination method, when combined with renewable energy, outperforms other methods both economically and environmentally. Notably, the RO method reduces net present cost (NPC) by 6.18% and 8.25% and carbon dioxide emissions by 38% and 46%, respectively, compared to MED and MSF methods. Additionally, sensitivity analysis, considering factors such as interest rate, photovoltaic panel cost, battery cost, and fuel cost, was conducted on NPC. The results showed that with a 2% decrease in the interest rate, the amount of NPC increases by about 2.4% due to the increase in the share of renewable energy. Therefore, reducing the interest rate helps to design a system with less carbon dioxide emissions. This work, by highlighting the economic and environmental implications of different desalination methods, as well as key cost factors, contributes to the optimal design of combined energy-water schemes for remote areas.