Can a Power Inverter Run a Space Heater?

A power inverter is a device that converts direct current (DC) electricity into alternating current (AC) electricity, which is the type of power used by most household appliances, including space heaters. While a power inverter can theoretically run a space heater, the feasibility and efficiency of this setup depend on several critical factors.

Inverter Size and Heater Wattage

The first and most important consideration is the size of the power inverter and the wattage of the space heater. The inverter must have a higher wattage rating than the space heater to ensure safe and efficient operation. As a general rule, the inverter should have a wattage capacity at least 20-30% higher than the space heater’s power consumption.

For example, a 750-watt inverter could potentially run a space heater with a wattage of less than 750 watts. However, a larger 1,500-watt peak inverter would be a better choice to handle a 750-watt space heater, as it would provide a comfortable safety margin and allow for any potential power surges or spikes.

Battery Capacity and Runtime

can a power inverter run a space heater

Another crucial factor to consider is the battery capacity and runtime of the power inverter setup. Space heaters are known to be power-hungry devices, and running one off a battery-powered inverter can quickly drain the battery.

As a general guideline, a 600-watt-hour battery can power a 600-watt space heater for approximately 20 minutes before the battery is depleted. To extend the runtime, you would need a larger battery bank or a more efficient heating solution, such as a propane or diesel-powered heater.

Heating Alternatives

If you’re looking to heat a small space using a power inverter, there are alternative heating solutions that may be more practical and efficient than running a traditional electric space heater:

Mr. Heater Propane Heater

The Mr. Heater Portable Buddy is a popular propane-powered heater that can be a good option for heating a small space. It doesn’t require an electrical connection, making it a suitable choice for off-grid or emergency situations. However, it’s essential to use a carbon monoxide alarm with this type of heater for safety.

Diesel Air Heater

Diesel air heaters are another alternative that can be powered by a power inverter. These heaters are designed to be more efficient and compact than traditional electric space heaters. They do require some installation, such as drilling a hole for the air intake and exhaust vent, but they can be a viable option for heating a small space.


In summary, a power inverter can run a space heater, but the size of the inverter and the wattage of the heater are crucial factors to consider. Battery capacity and runtime are also important considerations, as space heaters can quickly drain a battery-powered system. Alternative heating solutions, such as propane or diesel-powered heaters, may be more practical and efficient in certain situations.


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