A beginner’s guide to thermophotovoltaic-based thermal energy storage using high-temperature phase change materials

Abstract The rising global demand for reliable energy systems and the increased deployment of renewable energy infrastructure has increased the demand for efficient energy storage technologies capable of addressing the challenge of intermittency of renewable energy sources. Thermophotovoltaic (TPV)-based energy storage represents an emerging and potentially transformative approach that converts stored thermal energy into electricity through radiative photon emission and photovoltaic conversion. This tutorial paper provides an overview of the working principles, core systems components and operation of the TPV-based energy storage system, with a specific focus on latent heat storage using high-temperature Phase Change Materials (PCMs). This paper further explores the performance metrics of TPV energy conversion, and examines how PCM-based latent heat storage enables stable operation at temperatures above 1000 K. We further explored the key challenges related to efficiency losses, material degradation, costs and possible pathways for improvement, alongside recent experimental benchmarks and practical applications of TPV-based storage in long-duration energy storage, cogeneration and industrial waste heat recovery. By consolidating the current state of knowledge, technological progress, and research challenges, we aimed at providing a foundational understanding of TPV thermal storage systems and highlight their potential as a cost-effective and scalable pathway toward a sustainable energy future.