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Power & Backup
Generator & Backup Power Calculator
What size generator do you need? Add your appliances and equipment — we account for motor starting currents and safe continuous loading, then recommend the generator kVA, inverter size and battery bank. Free, instant, engineer-built.
1 · Add your equipment
2 · Your load list
LED lights (×10)
100 W each
1
100 W
Fridge / freezer
300 W each · motor start ×3
1
300 W
TV & decoder
150 W each
1
150 W
3 · Battery backup preferences
Your sizing result
- Running load
- 550 W
- Peak (with motor start)
- 1,150 W
- Recommended generator
- 2.5 kVA
Sized at 0.8 power factor with the continuous load held below 75% of rating — the way a generator should be run for engine life.
Inverter alternative
- Inverter size
- 1 kW
- Battery bank (4 h @ 48 V)
- 70 Ah
Lithium assumed (80% usable capacity, 90% inverter efficiency). Heavy heating loads (geyser, stove, kettle) are usually moved off inverter circuits — we design that split at assessment.
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