The Outage HouseKeep the essentials running when the power goes out
Room: Basement

Pellet Stove Battery Backup: UPS, Inverter or Power Station?

Guide type
Options compared
Last reviewed
Sources
14 cited
Tested by us
No. How we research

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Short answer

Start with your stove's manual, not with a battery. Most pellet stoves need electricity 1, and without it the combustion blower stops and smoke can enter the room 2. Harman approves only certain Tripp Lite units: an inverter/charger with a deep-cycle battery that can run the stove up to eight hours, and a small UPS that only shuts it down safely 3. A power station also works if it meets the stove maker's rules: Comfortbilt, for example, requires a pure sine wave with at least 1,000 W peak 4. Forge & Flame says most stoves typically draw 80 to 150 W once running 3.

Your outage load
150W · Pellet stove, running≈10 hon 2,048 Wh
Station sizeRuntime for this load
1,024 Wh≈ 5.1 h
2,048 Wh≈ 10 h
3,584 Wh≈ 18 h

How we calculate: capacity × 85 % usable5,6 ÷ (150 W load3 + 20 W the inverter uses on its own, our assumption: the maker does not publish it). Why these figures

Pellet stove in an outage

Never: run a generator inside the house or the garage, or near a window, door or vent 7,8.

What happens to a pellet stove when the power goes out

Unlike a wood stove, most pellet stoves need electricity, because an electric device feeds the pellets to the fire 1. A fan also pushes the smoke out. When the power cuts, the combustion blower stops and smoke can enter the room; Harman strongly recommends a battery backup to limit it 2.

Some stoves plan for this. Some Quadra-Fire pellet models come with a built-in battery backup 11. Check your manual before you buy anything.

How many watts a pellet stove uses

  • Harman P43, P61A and P68: 2.8 A running and 4.2 A at start-up, at 120 V 2. That is up to about 336 and 504 VA, maximums from the manual’s electrical rating.
  • Most stoves, according to Forge & Flame: 300 to 500 W to ignite, 80 to 150 W once running 3.

The ignition peak decides the unit’s output rating; the running draw decides how long a battery lasts.

Option 1: a UPS for a safe shutdown

A small UPS (uninterruptible power supply) keeps the stove powered just long enough to shut down cleanly. With Harman’s approved UPS, a stove with Rev E or later software pulses its blower every few seconds to clear the exhaust until the fire is out 2.

  • Tripp Lite INTERNET750U: on Harman’s list for this role only; it does not run the stove through an outage 3. Tripp Lite rates it at 2 minutes at full load and 8.6 minutes at half load, and switches over in 6 ms 10.
  • APC Back-UPS Pro BR1500MS2: 900 W with a sine wave output 12, but it is not on Harman’s list 3, and we could not read APC’s runtime chart. Ask your stove maker before relying on it.

Option 2: an inverter/charger with a deep-cycle battery

This is what Harman approves to keep its stoves running. The unit stays plugged into the wall, charges a 12 V deep-cycle battery that you buy separately, and switches to it when the power cuts.

  • Tripp Lite APS700HF: 700 W continuous, 1,400 W peak for up to 1.1 s, switchover in 16.6 ms 13. Harman says it can run the stove for up to eight hours and needs simple stove setting changes from a Harman dealer 3.
  • What to know: Harman asks for dealer setting changes 3, and the unit’s battery output is not a pure sine wave 13. The battery is not included, and Tripp Lite asks for a fuse close to it 13: have it installed properly.

Option 3: a portable power station

A power station is the same idea in one box: battery, charger and inverter. It must meet your stove maker’s rules.

  • EcoFlow DELTA 3 Plus: 1,024 Wh, 1,800 W, 3,600 W surge, pure sine wave, switchover in 10 ms 9. That meets Comfortbilt’s rule of a pure sine wave with at least 1,000 W peak 4. At 150 W, it runs a stove for about 5.1 hours; at 80 W, about 8.7 hours (our method: 85 % usable 5,6, plus 20 W for the station).
  • Set it up right: EcoFlow’s AC timeout turns an idle outlet off; set it to “never” in the EcoFlow app to be safe 9.
  • Stock: on 2026-11-10 it was on pre-order in the US and out of stock in Canada until early next year.

We show the DELTA 3 Plus as one example. The Jackery HomePower 3600 Plus also publishes a pure sine wave output 14; check any station against your stove maker’s written rules.

Which option fits your outages

Your situation Best fit
Harman stove An inverter/charger from Harman’s list, set up by the dealer 3
Short outages, safety first A UPS for a clean shutdown 3
Other brands, outages of a few hours A pure sine wave station that meets the maker’s rules 4
Built-in battery backup Follow the stove maker’s instructions 11

To size a battery for the stove and other appliances, use the power station calculator. For other heat sources, see how to heat your house during a power outage. Our method is on the how we research page.

Questions

Can a portable power station run a pellet stove?

It can, if it meets the stove maker's rules. Comfortbilt asks for a pure sine wave with at least 1,000 W peak 4; the EcoFlow DELTA 3 Plus publishes a pure sine wave and 3,600 W surge 9. Harman lists only Tripp Lite units 3, and its manual warns that some generator or battery backup systems may not be compatible with the stove's electronics 2, so ask your Harman dealer before using a station.

What are a pellet stove's power requirements?

Harman rates its P43, P61A and P68 stoves at 2.8 A running and 4.2 A at start-up, at 120 V 2: up to about 336 and 504 VA. Forge & Flame says most stoves draw 300 to 500 W to ignite and 80 to 150 W once running 3.

Will a UPS keep my pellet stove running?

A small UPS usually will not. The Tripp Lite INTERNET750U, which Harman lists, only cuts power for a safe shutdown 3; Tripp Lite rates it at 2 minutes at full load 10. To keep the stove running, Harman lists inverter/chargers with a deep-cycle battery 3.

Which battery backup does Harman approve?

Harman's site lists Tripp Lite units only: the APS700HF and APS750 inverter/chargers to run the stove, which need a 12 V deep-cycle battery and setting changes by a Harman dealer, and the INTERNET750U UPS for a safe shutdown 3.

Bottom line

For a Harman stove, buy from Harman's list and let the dealer set it up. For other brands, follow the maker's rule: a pure sine wave station like the DELTA 3 Plus can run a stove for hours. If you only want the stove to shut down cleanly, an approved UPS, such as Harman's INTERNET750U for Harman stoves, is enough 3.

Related guides

What we checked, and what we didn't

Checked
  • Harman's approved list and power figures, Comfortbilt's and Quadra-Fire's outage advice
  • Output, waveform, switchover time and runtime of each unit on its maker's spec sheet
  • Stock of the DELTA 3 Plus on 2026-11-10
Not checked
  • How your stove behaves on any of these units. We have not tested them.
  • Average power of stoves other than Harman's: only Forge & Flame's general range was found.
  • Runtime of the APC Back-UPS Pro: APC's runtime chart could not be read.
  • Idle draw of the EcoFlow DELTA 3 Plus: not published, so we assume 20 W.

Sources

  1. Frequent Questions about Wood-Burning Appliances (updated March 5, 2026) · U.S. EPA Burn Wise
  2. Harman P43, P61A and P68 pellet stove owner's manual · Harman (Hearth & Home Technologies)
  3. Winter storm outage? No problem (Harman approved battery backups) · Forge & Flame (Hearth & Home Technologies)
  4. Ensuring seamless power backup for your Comfortbilt pellet stove · Comfortbilt
  5. Jackery Explorer 1000 v2 review: measured 910 Wh of 1,070 Wh (July 23, 2026) · OutdoorGearLab
  6. The Best Portable Power Stations, Tested and Reviewed: output at 34 W and 380 W loads (updated May 5, 2025) · Outdoor Life
  7. What to Do to Protect Yourself During a Power Outage · U.S. Centers for Disease Control and Prevention
  8. Carbon monoxide: Preventing exposure · Health Canada
  9. EcoFlow DELTA 3 Plus user manual (US) · EcoFlow
  10. INTERNET750U UPS specification sheet · Tripp Lite (Eaton)
  11. Power outage tips (Quadra-Fire pellet stoves) · Forge & Flame (Hearth & Home Technologies)
  12. Back-UPS Pro BR1500MS2 datasheet · APC (Schneider Electric)
  13. APS700HF inverter/charger specification sheet · Tripp Lite (Eaton)
  14. Jackery HomePower 3600 Plus user manual · Jackery

Revision history

2026-11-10First version.