I’m installing a kitchen under the bed. A CD30 drawer fridge is perfect for this. It’s only 25cm high but holds 30 liters. Downside off course is the fact that you can’t store taller items standing up.
It’s a compressor fridge and energy efficient. The manual claims it uses 40 watts but some testing shows it only uses 2.2 amps @ 13,9V (about 30 watts) when the compressor and cooling fan are running with a small spike to 3 amps when the compressor kicks in. The requested temperature and the ambient temperature will determine how often the compressor and fan will run. The 110 watts solar panel and 110Ah AGM battery should provide enough power to run the fridge for 24 hours.
Ventilation and insulation
The unit doesn’t make much noise and most of it is coming from the fan. Considering the fridge will be under the bed, I expect it will be muffled to enough to not be a nuisance during the night. The ventilation is following a kind of “maze”. This will probably help with keeping the noise down. The fan will take air at floor level behind the water tanks. The warm air will be expelled underneath the sink.