Robust Multi-Objective Planning of Wind–Solar–Battery Integration under Desert Conditions: A Saudi Grid Case Study

Abstract

The Vision 2030 of Saudi Arabia aims to revolutionise the country's energy mix by incorporating large-scale renewable resources into the grid. The solar radiance and good wind conditions of the country are exceptional and provide good opportunities, but harsh desert conditions, characterised by extreme temperature, dust formation, and intermittency of resources, present a distinctive challenge to the integration reliability. Such factors are usually overlooked in existing literature, resulting in over-optimised performance estimates and poor system design decisions. The paper elaborates on a strong multi-objective optimisation model for the design of hybrid wind-solar-battery systems in deserts. The framework is a capacity sizing and storage dispatch optimisation in the conditions of uncertainty, with the clear-cut modelling of the temperature-dependent derating of PV, cutback of inverters, and the effect of soiling. Weather and load uncertainty are modelled using scenario-based simulations and Monte Carlo error modelling. An example of a Saudi case study that employed one year of hourly data illustrates some of the most important results. The best capacity mixes were slightly more favourable to wind resources, with inland nodes having 55% wind and 45% solar, and coastal nodes having 60% wind and 40% solar. Storage systems with 4-6 hours of energy to power ratio were the most effective, minimising curtailment by more than 60 percent compared to PV-only systems and minimising the loss of load probability to less than 1%. The best levelized cost of energy (46 USD/MWh) was obtained with the optimised hybrid configuration, which was optimal compared to all the baseline cases. These results prove that even small over-charging of storage and the complementarity of wind and solar can provide cost-effective and reliable integration of renewables in desert grids. The framework can be transferred to other arid locations where there is a desire to achieve high penetration in renewable energy.