Space heater 1500 W: how much battery you need
Space heater 1500 W draws about 1500 W (1000–2000 W range), runs 70% of the time and uses 6300 Wh per day. Start-up surge: 1500 W.
6+ kWh a night: the single appliance that makes battery backup pointless. Use gas, a wood stove or an electric blanket instead.
Battery needed
| Hours | Wh | Battery (Wh) | Inverter (W) |
|---|---|---|---|
| For 8 hours | 2100 | 3182 | 1651 / 1500 |
| For 24 hours | 6300 | 9546 | 1651 / 1500 |
| For 72 hours | 18900 | 28637 | 1651 / 1500 |
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Stations that fit (24 h)
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FAQ
How many watts does a Space heater 1500 W use?
Typically 1500 W while running, with a range of 1000–2000 W depending on model and age. Start-up surge can reach 1500 W.
How long will a 1000 Wh power station run a Space heater 1500 W?
About 0.6 hours on the clock, allowing for the 70% duty cycle, inverter losses and a 20% reserve.
What size power station do I need for a Space heater 1500 W overnight (8 h)?
About 3182 Wh of battery and an inverter rated at least 1651 W continuous with 1500 W surge.
Can I run a Space heater 1500 W on solar during an outage?
You need roughly 4200 W of panels in winter to replace a day's use (6300 Wh), charging through a station with a big enough MPPT input.
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