[jetbooster]

Without concentrating the sunlight, the max efficiency of a solar panel is about 68% conversion. With 1kW/m², and a solar panel the size of a 0.01m² phone (6.1 inch, 16:9) that's 6.8W to play with, at the theoretical maximum.

A quick check states a Raspberry Pi 4B at 100% CPU draws 6.4W, so in perfect conditions with a perfect panel, it's just about approaching feasible to run a chip on a phone sized panel.

However a Gameboy is much simpler than a Pi. It seems the Gameboy draws about 70-80mA@1.5V, or 0.1W, which is very impressive. I would say that would 100% be physically feasible to power with a gameboy sized solar panel in our lifetime.

[whoisthemachine]

That's interesting, with so much juice available, it seems like it would be worthwhile to pursue this project with the original hardware rather than adding in the snapshotting and emulation, which definitely makes a more robust system, but adds lots of extra power consumption.