This question is a repeat of another post on the physics board
Here and here show the possibility to combine photons of lower energy to higher energy. Thinking of an application, it could be used to dissipate heat from a laptop. A liquid cooling device could collect heat from a heat sink, then the device makes infrared photons with the heat and sends photons to an "upconversion" device. This device combines infrared into visible light photons and illuminates a conventional solar cell.
One would think of using a thermoelectric generator which still needs to dissipate heat. However, by imagination could "upconversion" package waste heat collected and turn it into light? My sentences may appear rudimentary as they are just ideas.