Inverter backup: how long will your battery last?
Battery energy = volts × amp-hours (12 V × 150 Ah = 1800 Wh), divide by the load in watts (and inverter losses) to estimate backup hours.
Power cut! How long will your inverter battery actually last? 🔋⏱️
1️⃣ DC → AC: your inverter takes 12 V DC from the battery and turns it into 230 V AC for your fans and lights. When the mains comes back, it charges the battery again.
2️⃣ THE MATHS: 12 V × 150 Ah = 1800 Wh stored. About 80 % reaches your loads after inverter losses → ≈ 1440 Wh.
Load: 2 fans (150 W) + 4 LED bulbs (40 W) + TV (60 W) + Wi-Fi (10 W) = 260 W.
1440 ÷ 260 ≈ 5.5 hours. (Real backup is often a bit less — older batteries and deep discharge reduce it.)
3️⃣ DON'T OVERLOAD IT: a typical 900 VA home inverter gives about 720 W max. Plug in a 2000 W geyser and it hits OVERLOAD and shuts off. Keep heaters, AC and geysers off the inverter.
📌 Backup hours ≈ volts × amp-hours × 0.8 ÷ your load in watts.
Read the voiceover (transcript)
- Power cut! How long will your inverter last?
- Your inverter turns twelve volts DC from the battery into two-thirty volts AC!
- Twelve volts times one-fifty amp-hours: eighteen hundred watt-hours. Fans, lights and a TV? About five hours!
- Plug in a geyser? Overload! It shuts off.
- Volts times amp-hours, divided by your load!
- Next: solar panels! Follow for part eight!
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