Gas Furnace Battery Backup: Keep the Heat On in a Winter Outage
A gas furnace needs electricity for its blower and controls. How much battery keeps it running through a freezing night, and how to connect it safely.
Updated October 27, 2026 · By the OutageWatt team · How we calculate
In short
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Heat for the whole house, on a fraction of the power
Gas does the heating; electricity only moves the air and runs the controls. That makes a furnace the most efficient way to keep a house warm on battery: the same energy that runs a space heater for an hour can keep a blower going for most of a night.
Our numbers use Generac's conservative 875 W for a 1/2 HP blower. If your furnace has a variable-speed (ECM) motor, the draw on low speed can be a fraction of that: open the panel and read the motor label, then type it into the planner.
Furnace blower alone, 12 hours a day
| Power station | Capacity | Runs it? | Runtime | Price |
|---|---|---|---|---|
| Jackery Explorer 1000 v2 | 1.1 kWh | Can't start it | — | $499 |
| EcoFlow DELTA 3 Plus | 1.0 kWh | Yes | 2.1 h | $719 |
| Anker SOLIX C1000 Gen 2 | 1.0 kWh | Can't start it | — | $499.99 |
| BLUETTI AC180 | 1.2 kWh | Surge not published | — | $499 |
| Anker SOLIX F2000 | 2.0 kWh | Surge not published | — | $1,999 |
| Jackery HomePower 2000 Plus v2 | 2.0 kWh | Yes | 4.1 h | $1,069 |
| Jackery HomePower 3600 Plus | 3.6 kWh | Yes | 7.2 h | $1,709 |
| BLUETTI Apex 300 | 2.8 kWh | Yes | 5.6 h | $1,599 |
| Anker SOLIX F3800 Plus | 3.8 kWh | Yes | 7.7 h | $2,399.99 |
| EcoFlow DELTA Pro 3 | 4.1 kWh | Yes | 8.2 h | $2,799 |
| Jackery HomePower 3600 Pro Max | 3.6 kWh | Yes | 7.2 h | $1,799 |
| Jackery Explorer 5000 Plus | 5.0 kWh | Yes | 10 h | $3,149 |
The full winter list
| Power station | Capacity | Runs it? | Runtime | Price |
|---|---|---|---|---|
| Jackery Explorer 1000 v2 | 1.1 kWh | Output too low | — | $499 |
| EcoFlow DELTA 3 Plus | 1.0 kWh | Can't start it | — | $719 |
| Anker SOLIX C1000 Gen 2 | 1.0 kWh | Can't start it | — | $499.99 |
| BLUETTI AC180 | 1.2 kWh | Surge not published | — | $499 |
| Anker SOLIX F2000 | 2.0 kWh | Surge not published | — | $1,999 |
| Jackery HomePower 2000 Plus v2 | 2.0 kWh | Yes | 3.5 h | $1,069 |
| Jackery HomePower 3600 Plus | 3.6 kWh | Yes | 6.1 h | $1,709 |
| BLUETTI Apex 300 | 2.8 kWh | Surge not published | — | $1,599 |
| Anker SOLIX F3800 Plus | 3.8 kWh | Yes | 6.6 h | $2,399.99 |
| EcoFlow DELTA Pro 3 | 4.1 kWh | Yes | 7.0 h | $2,799 |
| Jackery HomePower 3600 Pro Max | 3.6 kWh | Yes | 6.1 h | $1,799 |
| Jackery Explorer 5000 Plus | 5.0 kWh | Yes | 8.6 h | $3,149 |
| Battery | Usable | Output | Runtime |
|---|---|---|---|
| Tesla Powerwall 3 (1 unit) | 13.5 kWh | 11.5 kW | 24 h |
| Enphase IQ Battery 5P (1 unit) | 5.0 kWh | 3.84 kW | 8.8 h |
| FranklinWH aPower 2 (1 unit) | 15.0 kWh | 10 kW | 26 h |
| Tesla Cybertruck (Powershare) | 98.4 kWh | 11.5 kW | 7.2 days |
| Ford F-150 Lightning (Extended Range) | 104.8 kWh | 9.6 kW | 7.6 days |
| Kia EV9 (Long Range) + Wallbox Quasar 2 | 79.8 kWh | 12 kW | 5.8 days |
Wiring
Because furnaces are usually hard-wired, the safe options are a dedicated furnace transfer switch next to the unit or a panel transfer switch. Both need a licensed electrician. See transfer switch options.
Stations sized for winter nights
Picked from the makers' published specs and US store prices, checked October 28, 2026. We haven't tested them ourselves, and we may earn a commission if you buy through these links, at no extra cost to you. The full comparison is on our power station page.
EcoFlow
DELTA Pro 3
4 kWh with 120/240 V; grows to 12 kWh per unit. EcoFlow's Smart Generator can top it up on long outages.
- Capacity
- 4.1 kWh
- Output
- 4.0 kW · 240 V
- Surge
- 8.0 kW†
- Solar in
- 2.6 kW†
- Weight
- 113.5 lb†
- Warranty
- 5 yr
† reported by retailers or reviews, not yet confirmed on EcoFlow's spec sheet.
$2,799list $3,299 · out of stock when checked, October 28, 2026
Check price
Anker SOLIX
F3800 Plus
6,000 W at 240 V runs a well pump and most circuits through a transfer switch; six expansion batteries per unit.
- Capacity
- 3.8 kWh
- Output
- 6.0 kW · 240 V
- Surge
- not published
- Solar in
- 3.2 kW
- Weight
- 136.7 lb
- Warranty
- 5 yr
$2,399.99after on-site coupon, October 28, 2026
Check priceFrequently asked questions
Does a gas furnace work without electricity?
No. A modern gas furnace needs electricity for its igniter, controls, inducer fan and blower. Without power it won't light, even with gas flowing.
How many watts does a furnace blower use?
Generator charts size a 1/2 HP blower at about 875 W running and 2,300 W extra to start; DTE Energy lists 600 W for 1/2 HP. Newer variable-speed (ECM) blowers often draw a few hundred watts. The label inside the furnace door has your number.
Can I plug my furnace into a power station?
Most furnaces are hard-wired, so the safe way is a furnace transfer switch or a panel transfer switch installed by a licensed electrician. Some installations use a plug and receptacle that make swapping to a battery possible; check local code.
Free tool
Plan the winter outage
Type your blower's label watts for a precise runtime.
OutageWatt is independent and not affiliated with any brand named here. Specs come from makers' spec sheets and are dated; anything wired into your home needs a licensed electrician and a transfer switch or interlock. Never backfeed through an outlet.