Oscillating thermal resources are ubiquitous thanks to the diurnal cycle and are also found in nonsolar settings. Yet in isolation, oscillating thermal resources cannot normally generate electricity because standard heat engines require two thermal terminals, a source and a sink, and hence the engine’s second terminal is typically connected to some nearby constant-temperature reservoir. As an alternative, here we introduce the “temperature doubler” thermal circuit, based on two thermal diodes and two thermal capacitances. Modeling reveals how the electrical power output depends on the thermal diodes and masses. Benchtop experiments match the modeling well with no free parameters. Experiments further show that the temperature doubler generates four times more electricity than a conventional approach using a static heat sink, with a theoretical limit of an 8-fold enhancement for perfect thermal diodes and large thermal masses. This study shows how high-performance nonlinear thermal elements enable new approaches to more effective thermal-to-electrical energy conversion.

由于昼夜循环，振荡热资源无处不在，并且在非太阳环境中也能找到。然而孤立地，振荡热源通常不能发电，因为标准热机需要两个热终端，一个源和一个接收器，因此发动机的第二个终端通常连接到附近的某个恒温水库。作为替代方案，我们在此介绍基于两个热二极管和两个热容的“温度倍增器”热回路。建模揭示了电功率输出如何取决于热二极管和质量。台式实验与没有自由参数的建模很好地匹配。实验进一步表明，温度倍增器产生的电量是使用静态散热器的传统方法的四倍，对于完美的热二极管和大热质量，理论极限为 8 倍增强。这项研究展示了高性能非线性热元件如何实现更有效的热能到电能转换的新方法。