That's very smart and might end my quest for a truly quiet bedroom fridge, if it really only runs two minutes in an hour. (Light fridges marketed as "quiet" just produce near-constant annoying fan noise, quietly.)

It really works, and if you fill half the space with water then it'll only need to run once or twice a week (assuming you don't open the lid often)

Have you looked at hotel minibar fridges? They're generally pretty quiet.