Short Runtime UPS
The cheapest option when it comes to having a form of battery backup is to purchase UPS without an extra battery pack. A UPS by itself can only be expected to provide backup power for a short period of time. How long the runtime will be is heavily dependent on the efficiency of your fridge. Modern European energy efficient under counter fridge may provide four hours of runtime. In contrast, the majority of upright vaccine fridges found in pharmacies and medical centres around Australia can only be expected to achieve a runtime of half an hour.