Air conditioner 12k BTU: how much battery you need
Air conditioner 12k BTU (inverter) draws about 1000 W (600–1500 W range), runs 50% of the time and uses 4000 Wh per day. Start-up surge: 1800 W.
4–6 kWh per 8-hour night; realistic only with a 5 kWh+ system or a generator. Inverter units soft-start; old on/off units surge 3×.
Battery needed
| Hours | Wh | Battery (Wh) | Inverter (W) |
|---|---|---|---|
| For 8 hours | 1333 | 2021 | 1100 / 1800 |
| For 24 hours | 4000 | 6061 | 1100 / 1800 |
| For 72 hours | 12000 | 18182 | 1100 / 1800 |
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Stations that fit (24 h)
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FAQ
How many watts does a Air conditioner 12k BTU (inverter) use?
Typically 1000 W while running, with a range of 600–1500 W depending on model and age. Start-up surge can reach 1800 W.
How long will a 1000 Wh power station run a Air conditioner 12k BTU (inverter)?
About 1.3 hours on the clock, allowing for the 50% duty cycle, inverter losses and a 20% reserve.
What size power station do I need for a Air conditioner 12k BTU (inverter) overnight (8 h)?
About 2021 Wh of battery and an inverter rated at least 1100 W continuous with 1800 W surge.
Can I run a Air conditioner 12k BTU (inverter) on solar during an outage?
You need roughly 2667 W of panels in winter to replace a day's use (4000 Wh), charging through a station with a big enough MPPT input.
Other sizes
Other appliances
1 Approximate values: estimated from motor or heater power and typical figures published online, not from a manufacturer chart. Check your appliance label.
Inverter efficiency 88%, usable depth of discharge 90%, reserve 20%. Full method: How we calculate. source