Photonic crystal emitter design and associated efficiency optimization of radioisotope thermophotovoltaic generators

Abstract

The radioisotope batteries have drawn extensive attention due to the high energy density. Nowadays, the radioisotope thermophotovoltaic systems are one of the most promising radioisotope batteries. In this work, the crystal emitter design and the associated performance of the radioisotope thermophotovoltaic generators are investigated. First, the design of photonic crystal emitter together with the adoptions of both the multi-layer insulation and supporting materials are discussed. In order to optimize the system efficiency, the effects of the area of emitters are mainly investigated. We have analyzed the efficiency of system using GaSb cells and Si cells, respectively. With Si cells, the system efficiency can computationally reach about [Formula: see text] with an output power of 7 W. When GaSb cells are employed, the system performance is estimated to an efficiency of [Formula: see text] with 61.6 W output.

Nuclear batteries: Current context and near‐term expectations

“…What clearly emerges from the recent literature is that, regardless of the nature of the photonic crystal, in the RTPV systems an appropriate design of the source and of the emitter surface represent the key factor to increase the performances of the devices. An example is the notable increase of efficiency (up to 12.3%) obtained from a 238 Pu source by the shaping of the emitter coupled with a GaSb cell 94 …”

“…An example is the notable increase of efficiency (up to 12.3%) obtained from a 238 Pu source by the shaping of the emitter coupled with a GaSb cell. 94 As regards the first step of the mechanism driving the RTPV systems, a more efficient thermal-optical conversion can be achieved by making the process to occur precisely on the surface of the heat source. This new approach relies on the coating of the solid radiation sources by high-emissivity materials, able to efficiently convert heat into I.R.…”