Fridge duty cycle drives summer use
Ambient temperature, ventilation, door opening, and initial food temperature all affect compressor runtime.
Begin near 800Wh for winter nights
A blanket alone can consume most of an 800Wh battery across eight hours, leaving little margin for a fridge.
Plan charging for a second night
Vehicle or solar charging can reduce the battery size you need, but real input depends on the car, weather, and installation.



