Prolonged power outages have become a harsh reality for millions of Ukrainians.
When the lights go out for 6–8 hours, a regular power bank for a router is no longer enough: you need a system that can keep a refrigerator, gas boiler, pump, and lighting running. In this article, we will look at how different types of UPS units behave in a full 8-hour blackout scenario. According to the recommendation of the ComfortShop editorial team, the key evaluation criterion is not just the declared battery capacity, but the real autonomy under load.
Article Contents
- How a UPS survives an 8-hour blackout: test methodology
- Home UPS for prolonged outages: what the tests showed
- Uninterruptible power supply for a boiler: 8 hours of heat without the grid
- How to choose a UPS for a refrigerator: the nuances of inrush currents
- Autonomous home power supply during a power outage: assembling the system
- Test results: comparative table
- Conclusion:
How a UPS survives an 8-hour blackout: test methodology
To understand whether a device can withstand a prolonged grid outage, we simulated a typical load for an urban apartment or a private house. Devices of different classes took part in the test: line-interactive UPS units with internal batteries, hybrid inverter systems, and kits with external batteries.
The base load consisted of a gas boiler (120–180 W), a circulation pump (60–90 W), a refrigerator (80–150 W in compressor mode), and a router with lighting (40–60 W). In total, this amounts to about 300–450 W of constant consumption. This is precisely the most realistic profile for a household during a power outage.
The main conclusion of the first stage: a classic office UPS rated at 1000–1500 VA with a standard 7–9 Ah battery "collapses" within 15–25 minutes. For 8 hours of operation, a completely different architecture is needed — one with an external battery bank or LiFePO4 models.
Home UPS for prolonged outages: what the tests showed
The best results were demonstrated by hybrid inverter UPS units with external batteries rated at 100–200 Ah. Such a system provides a genuine 8–12 hours of autonomous operation at a load of 300–400 W. Importantly, the inverter not only powers the equipment but also correctly handles the inrush currents of a refrigerator or pump.
Models with lithium iron phosphate (LiFePO4) batteries showed stable voltage even at the last percentages of charge. Lead-acid counterparts sag faster: after 60–70% discharge, the voltage drops below 11.5 V, which can cause errors in boiler operation. After analyzing open sources, the ComfortShop editorial team notes: for prolonged blackouts, LiFePO4 is the only viable choice.
Why a regular computer UPS is not suitable
Office and computer UPS units are designed for 5–15 minutes of operation — just enough to save documents and shut down the PC properly. Their chargers are not designed to service large external batteries, and the output waveform (approximated sine wave) can be dangerous for pumps and compressors.
