https://www.pcgamer.com/a-liquid-cooled-power-supply-sounds-like-a-terrible-idea-but-it-exists/

When considering the best power supply unit for PC gaming, cooling is one of the considerations, but one thing that is not on our checklist is liquid cooling. Don't tell that to FSP. The PSU maker has been cranking out liquid cooled PSUs for a few years now, and they are selling well enough that it just released a new 850W model.

FSP created its new Hydro PTM+ 850W in collaboration with Bitspower, which makes all kinds of liquid cooling equipment, including full-length waterblocks for graphics cards. In this case, the PSU features an integrated liquid cooling solution to keep it cool and quiet.