How long will a EcoFlow DELTA Pro Ultra (1 battery) keep your power on?
With no sun, one EcoFlow DELTA Pro Ultra (1 battery) runs a fridge, freezer, furnace fan, lights, Wi-Fi, TV and microwave for about 18 h. Add a portable solar panel and it lasts longer on sunny days.
EcoFlow’s DELTA Pro Ultra stacks 6 kWh battery modules on a 7.2 kW inverter and can connect to a home through a transfer panel.
Runtime for one appliance at a time
| Appliance | kWh/day | Runtime | Power OK? |
|---|---|---|---|
| Refrigerator | 1.4 | 3.8 days | ✓ |
| Chest freezer | 0.8 | 6.5 days | ✓ |
| Modem + Wi-Fi router | 0.5 | 10.8 days | ✓ |
| LED lights (6 rooms) | 0.3 | 17.3 days | ✓ |
| Phones & laptop charging | 0.2 | 28.8 days | ✓ |
| Gas furnace blower (winter) | 3.0 | 41 h | ✓ |
| TV + streaming box | 0.5 | 10.8 days | ✓ |
| Box / ceiling fans (2) | 0.8 | 6.5 days | ✓ |
| Window AC (one room) | 7.2 | 17 h | ✓ |
| Central AC (3-ton) | 28.0 | 4 h | ✓ |
| Heat pump heating (winter) | 30.0 | 4 h | ✓ |
| Space heater | 6.0 | 21 h | ✓ |
| Well pump (1 hp) | 1.0 | 5.2 days | ✓ |
| Sump pump (⅓ hp, storm) | 1.6 | 3.2 days | ✓ |
| Electric water heater | 9.0 | 14 h | ✓ |
| CPAP (no humidifier) | 0.3 | 16.2 days | ✓ |
| Oxygen concentrator | 8.4 | 15 h | ✓ |
| Microwave | 0.3 | 15.7 days | ✓ |
| Coffee maker | 0.2 | 28.8 days | ✓ |
| Electric cooktop (1 burner) | 1.1 | 4.6 days | ✓ |
| Washing machine (1 load) | 0.5 | 10.4 days | ✓ |
| EV charging (Level 1, 120 V) | 5.6 | 22 h | ✓ |
Typical running watts × hours a day; starting full, no recharge. “Check surge” means the motor’s start-up draw may exceed the battery’s surge rating.
Runtime for common outage plans
| What stays on | kWh/day | 1 unit | 2 units |
|---|---|---|---|
| Keep the food cold & lights on | 2.3 | 54 h | 4.5 days |
| Essentials + furnace fan + TV | 6.9 | 18 h | 36 h |
| Rural: essentials + well + sump | 6.0 | 21 h | 41 h |
| Summer outage with window AC | 10.8 | 12 h | 23 h |
| Medical: CPAP + essentials | 2.6 | 47 h | 3.9 days |
| Most of the house incl. central AC | 33.5 | 4 h | 7 h |
“✗ power” means everything switched on at once would draw more than the battery can deliver.
Questions about the EcoFlow DELTA Pro Ultra (1 battery)
How long will a EcoFlow DELTA Pro Ultra (1 battery) run a refrigerator?
About 3.8 days on its own, with no solar recharge, for a typical fridge using 1.4 kWh a day.
Can a EcoFlow DELTA Pro Ultra (1 battery) run central air conditioning?
It can supply the roughly 3.5 kW a 3-ton unit draws, but at about 28 kWh on a hot day it would empty quickly. Check its motor-start (surge) rating with your installer.
How many EcoFlow DELTA Pro Ultra (1 battery) units do I need for whole-home backup?
Roughly 5 for a house with central AC and electric cooking, sized both for energy (a day of use) and for power (everything running at once). For essentials only, one or two are usually enough.
Can solar panels recharge a EcoFlow DELTA Pro Ultra (1 battery) during a power outage?
Yes, from its own solar inputs or a connected array.
Compare with other batteries
| Battery | Usable kWh | kW | Essentials runtime |
|---|---|---|---|
| Tesla Powerwall 3 | 13.5 | 11.5 | 44 h |
| FranklinWH aPower 2 | 15 | 10 | 49 h |
| Enphase IQ Battery 5P | 5 | 3.84 | 16 h |
| SolarEdge Home Battery | 9.7 | 5 | 32 h |
| Generic 10 kWh home battery | 10 | 5 | 33 h |
| Anker SOLIX F3800 | 3.84 | 6 | 11 h |
| Jackery Explorer 2000 Plus | 2.04 | 3 | 6 h |
| EcoFlow DELTA 2 (1 kWh class) | 1.02 | 1.8 | 3 h |
Specifications are manufacturer figures as of September 2026. We are not paid by any manufacturer. Verify the current datasheet before you buy.