Modeling and Experimental Study of a Dual‐Receiver Parabolic Solar Concentrator for Direct Electricity Generation and Thermal Storage for Isolated Sites

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ABSTRACT Approximately 64% of the population of sub‐Saharan Africa lives in isolated villages without access to electricity, even though this region is among the areas of the world with the highest solar potential. One of the solar technologies capable of meeting the energy needs of both isolated and urban sites in sub‐Saharan Africa in a permanent and environmentally sustainable manner is concentrated solar power (solar thermodynamic). Thermodynamic solar energy encompasses a range of technologies that harness solar radiation to generate heat, which is subsequently converted into electricity through a thermodynamic cycle. Among these technologies, parabolic solar concentrators stand out for their high thermal efficiency and their suitability for decentralized applications, particularly in remote areas (0.04 ha/MW). However, deployment remains constrained by challenges related to thermal energy storage. This study focuses on the design, construction, and testing of a parabolic solar concentrator equipped with two receivers located at its focal point: a Stirling engine for direct electricity generation and a boiler that heats a heat‐transfer fluid to supply thermal energy to a storage battery. The system, featuring a reflective surface area of 4.27 m 2 , was evaluated through both theoretical modeling and experimental validation. Theoretical results predicted focal‐point temperatures of 714°C in 240 s, 350°C in the boiler after 1500 s, and 320°C in the serpentine coil over the same period. Under experimental conditions with an ambient temperature of 40°C, the system achieved a focal‐point temperature of 340°C within 1600 s. After 2000 s of operation, the recorded temperatures were 270°C in the boiler and 191°C in the heat exchange coil. The thermal energy accumulated in the boiler is subsequently stored and utilized for electricity generation during periods of solar intermittency. By using two receivers at the focal point of the parabolic concentrator, these results demonstrate the system's potential to ensure continuous solar‐electricity generation by integrating effective thermal storage.

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