Differential Evolution for Peak Demand Aware Economical Sizing of Photovoltaic Systems

The ever-increasing energy demand is envisioned to be met by renewables in the future. Traditional sizing techniques of PV systems are based on optimizing the economic benefit of rooftop owners with no regard to the impacts on the electrical grid. This paper presents a high-level multi-objective PV sizing model to maximize the rooftop owner’s Net Present Value (NPV) while minimizing the yearly peak demand. The proposed model optimizes the system size, tilt angle, and azimuth angle and is solved using the differential evolution (DE) algorithm. One case study of a residential home in Saudi Arabia was conducted to evaluate the performance of the proposed model. The case study results showed that systems that favor maximizing the NPV tend to have smaller system sizes and lower tilt angles. On the other hand, systems that favor minimizing the peak demand tend to prefer larger system sizes and higher tilt angles. The choice of the azimuth angles was consistent across both objectives. Overall, sizing PV systems using the proposed model can result in systems that achieve a positive return for the rooftop owner while minimizing the peak demand by 4.18% compared to approaches that purely optimize the economic benefit of the rooftop owner. Index Terms–Photovoltaic Sizing, Multi-objective optimization, Differential Evolution