Application of a multi-objective approach integrating solar-wind co-generation with response surface method to optimize zero-energy buildings
Ehsanolah Assareh, Nima Izadyar, Elmira Jamei, Saleh Mobayen, Majid Abbasi, Hassan Mohammadi, Neha Agarwal, Moonyong Lee
Abstract
• Optimal solar-wind system achieves Zero-Energy Building goals in severe climates. • Pitch angle control increases wind turbine efficiency and system reliability. • Energy and exergy efficiencies of 33.05 % and 34.02 % achieved via optimization. • Response Surface Method enhances performance via multi-variable system analysis. • System integrates renewable energy to cut CO 2 emissions by 1,334.47 tons annually. Achieving zero energy in residential buildings is particularly challenging in hot climates due to high cooling loads and reliance on conventional energy. This study introduces a co-generation system integrating a hybrid solar-wind setup with a Modified Steam Rankine Cycle and a Reverse Osmosis desalination unit to supply electricity, thermal energy, cooling, and potable water to a 360 m2 apartment complex in Ahvaz, Iran. BEopt software was used to extract energy consumption data, while energy and exergy assessments were performed using the Engineering Equation Solver and Response Surface Method. The system achieves an Exergetic Round Trip Efficiency of 34.02 % and an Energy Efficiency of 33.05 %. It meets annual energy needs with surplus energy fed back to the grid, generating 1,672 kWh of power, 8,760 kWh of heating, and 1,279 kWh of cooling while reducing 1,334.47 tons of carbon dioxide emissions. Pitch angle control in the 5 MW wind turbine enhances electricity generation by 4 %, leading to annual outputs of 6,541,564 kWh of electricity, 14,717,841 kWh of heating, 2,023,099 kWh of cooling, and 380,858 m3 of freshwater. The system stores excess thermal regulation for heating and air conditioning energy, contributing to cost-effectiveness and ecological sustainability. This study highlights the system’s ability to achieve net-zero energy, with significant reductions in carbon emissions and the provision of substantial freshwater, demonstrating its potential in extreme climates. Future studies can explore the dynamic optimization of hybrid systems, focusing on real-time energy distribution between cooling, desalination, and energy storage.