Concentrated Near-Field Thermoradiative Device Approaching Solar Cell Performance at Nighttime

Thermoradiative (TR) cells operate by harnessing the outgoing thermal radiation from Earth to outer space to extract work. Despite recent advancements in nighttime power generators, TR technology faces challenges with low output power and efficiency, falling far less than its theoretical limits. In this letter, we investigate the key limiting factors affecting performance metrics. By introducing a near-field atmosphere coupler composed of a polar dielectric absorber and a concentrated thermal emitter with optimized parameters, the maximum output power could be boosted to 180 W/m² with a 20-fold increase in the emission area, approaching the level of solar panels. Additionally, we explore material selection and integration strategies to showcase the feasibility and challenges of this technology. Our findings indicate that, analogous to the role of concentrated solar power in the solar power landscape, this technology could herald an emerging frontier for researchers in the field of renewable energy generation.