A Scalable Optimization Framework for High-Efficiency Central Receivers Using Additively Manufactured Micro-Pin Unit Cells

Abstract This article presents the development and demonstration of an optimization framework for the design of a megawatt scale central solar thermal receiver composed of multiple unit cells containing arrays of micro-pins. The framework tailors the pin geometry in each unit cell across the receiver surface in response to the design incident flux. The framework is demonstrated by designing a megawatt scale thermal central receiver for heating supercritical carbon dioxide from 500 °C to 720 °C while maintaining the maximum surface temperature below 800 °C to ensure long-term structural integrity and creep life. Key findings reveal that the optimized receiver design significantly outperforms a uniform geometry baseline. The summer-optimized configuration achieves a 14.2% higher outlet temperature (761 °C versus 666 °C) and a 2% point gain in thermal efficiency (93% versus 91%), all while maintaining structural and hydraulic constraints. The approach can be modified for different working fluids, operational conditions, material constraints, and applications. This work provides a scalable and practical pathway for developing designs of high efficiency, additively manufactured solar receivers that can adapt to real-world solar flux variability for producing power and process heat.