Song Jaeman, Choi Minwoo, Lee Bong Jae
Department of Mechanical Engineering, College of Engineering, Kyung Hee University, Yongin 17104, South Korea.
Department of Mechanical Engineering, KAIST, 291, Daehak-ro, Yuseong-gu, Daejeon-si 34141, South Korea.
Nanophotonics. 2023 Nov 8;13(5):813-823. doi: 10.1515/nanoph-2023-0572. eCollection 2024 Mar.
Thermophotovoltaic (TPV) energy converters hold substantial potential in converting thermal radiation from high-temperature emitters into electrical energy through photovoltaic (PV) cells, offering applications ranging from solar energy harvesting to waste heat recovery. Near-field TPV (NF-TPV) devices, focused on enhancing power output density (POD), exhibit unique potential by harnessing photon tunneling. However, this potential can be mitigated by additional losses arising from high photocurrent densities and corresponding scalability issues. This study comprehensively investigates the effectiveness of multi-junction-based NF-TPV devices, accounting for additional losses. We propose two approximative expressions to quantify the impact of additional losses and characterize current density-voltage curves. Verification against rigorously optimized results establishes a criterion for effective performance. Our method provides precise POD estimations even for devices with 10 or more subcells, facilitating performance analysis across parameters like vacuum gap distance, cell width, emitter temperature, and the number of subcells compared to far-field counterparts. This research outlines a roadmap for the scalable design of NF-TPV devices, emphasizing the role of multi-junction PV cells. The analytical framework we developed will provide vital insights for future high-performance TPV devices.
热光伏（TPV）能量转换器在通过光伏（PV）电池将高温发射器的热辐射转化为电能方面具有巨大潜力，其应用范围涵盖从太阳能收集到废热回收。近场TPV（NF - TPV）器件专注于提高功率输出密度（POD），通过利用光子隧穿展现出独特潜力。然而，这种潜力可能会因高光电流密度产生的额外损耗以及相应的可扩展性问题而受到削弱。本研究全面调查了基于多结的NF - TPV器件的有效性，并考虑了额外损耗。我们提出了两个近似表达式来量化额外损耗的影响并表征电流密度 - 电压曲线。与经过严格优化的结果进行验证，确立了有效性能的标准。我们的方法即使对于具有10个或更多子电池的器件也能提供精确的POD估计，与远场同类器件相比，便于对诸如真空间隙距离、电池宽度、发射器温度和子电池数量等参数进行性能分析。本研究概述了NF - TPV器件可扩展设计的路线图，强调了多结PV电池的作用。我们开发的分析框架将为未来的高性能TPV器件提供重要见解。
