In short
The EcoFlow DELTA Pro 3 comes out ahead on 3 of six outage scenarios. The real difference is what they can start: window ac, 12,000 btu (DELTA Pro 3 only).
We may earn a commission if you buy through links on this page, at no extra cost to you. It never changes a result. Specs from each maker, prices checked October 28, 2026; we haven't tested these units.
BLUETTI
Native 120 and 240 V with a 50 A outlet: built to feed a transfer switch, and expandable to whole-home capacity.
† reported by retailers or reviews, not yet confirmed on BLUETTI's spec sheet.
$1,599Halloween price, list $1,699, October 28, 2026
Check price
EcoFlow
4 kWh with 120/240 V; grows to 12 kWh per unit. EcoFlow's Smart Generator can top it up on long outages.
† 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 priceEach starts at 6 p.m., battery only. Extra batteries are added when the maker sells them and the outage needs them.
| Scenario | Apex 300 | DELTA Pro 3 | Better pick |
|---|---|---|---|
| Fridge, Wi-Fi & lights24 h | 24 h+ | 24 h+ | Tie |
| Storm night + sump pump48 h | Can't start your biggest motor | 2.0 days+ (+2 batt.) | DELTA Pro 3 |
| CPAP + fridge24 h | 24 h+ | 24 h+ | Tie |
| Rural: well pump & freezer72 h | Can't start your biggest motor | 2.7 days (+2 batt.) | DELTA Pro 3 |
| Winter: gas furnace72 h | Can't start your biggest motor | 21 h (+2 batt.) | DELTA Pro 3 |
| Hurricane week168 h | Not enough continuous output | Not enough continuous output | Tie |
| Spec | BLUETTI Apex 300 | EcoFlow DELTA Pro 3 |
|---|---|---|
| Battery | 2.8 kWh LFP | 4.1 kWh LFP |
| Expandable to | 19 kWh | 12 kWh |
| Continuous output | 3.8 kW | 4.0 kW |
| Start-up surge | not published | 8.0 kW |
| 240 V | Yes | Yes |
| Solar input | 2.4 kW | 2.6 kW |
| Weight | 83.8 lb | 113.5 lb |
| Warranty | — | 5 years |
| Panel connection | BLUETTI home backup kits with transfer switch | Smart Home Panel 2 (installed) |
| Price | $1,599 | $2,799 |
Appliances only one of them can start on its own: Window AC, 12,000 BTU (DELTA Pro 3).
The EcoFlow DELTA Pro 3 comes out ahead on 3 of six outage scenarios. Scenario by scenario results are in the table on this page; they come from published specs, not hands-on tests.
The BLUETTI Apex 300 can, for about 2.3 days on one charge. The EcoFlow DELTA Pro 3 can, for about 3.4 days on one charge.