For homeowners who want a 240V-capable backup battery that grows with expansion packs, not a grab-and-go unit.
Amazon $1,498.98 BLUETTI $1,499The BLUETTI Apex 300 rates 4.1 among large portable power stations; the EcoFlow DELTA 3 Ultra Plus rates 3.7 among home backup ones. The BLUETTI Apex 300 costs $100.02 less ($1,498.98 vs $1,599).

A wheeled 3kWh home-backup station that can grow to 11 kWh and charge fast from solar. The pick in this line for off-grid cabins and longer outages.
Amazon $1,599Prices were last checked October 24, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Scores side by side
These two sit in different size classes (large and home backup), and each is scored against the reference points for its own class, so a rating says how well each does among its own size peers. How we rank explains each factor.
| Factor weight | BLUETTI Apex 300 | EcoFlow DELTA 3 Ultra Plus |
|---|---|---|
| Overall rating | 4.1/5 | 3.7/5 |
| Value 25% | 63 $0.54 per rated Wh | 66 $0.52 per rated Wh |
| Tested capacity 15% | 68 85% of rated capacity delivered (1 test) | 68 85% of rated capacity delivered (1 test) |
| Battery life 15% | 100 LiFePO4, 6,000 cycles, 5-year warranty | 70 LiFePO4, 5-year warranty |
| AC output 15% | 100 3,840 W continuous AC | 37 3,600 W continuous AC |
| Charging speed 10% | 50 full AC charge time not published (neutral score used) | 50 full AC charge time not published (neutral score used) |
| Portability 10% | 50 73 Wh per kg (83.8 lb (38 kg)) | 84 91 Wh per kg (74.3 lb (33.7 kg)) |
| Solar input 5% | 84 2,400 W max solar input | 44 1,600 W max solar input |
| Features 5% | 80 UPS (0 ms), expandable, app | 100 UPS (10 ms), expandable, 140 W USB-C, app |
Independent capacity tests
BLUETTI Apex 300
| Tested by | Usable AC energy | Of rated | Conditions |
|---|---|---|---|
| The Solar Lab | - | 85% | Efficiency calculated from a variety of loads through the AC outlets; idle draw about 20W. |
EcoFlow DELTA 3 Ultra Plus
| Tested by | Usable AC energy | Of rated | Conditions |
|---|---|---|---|
| StorageReview | 2,610 Wh | 85% | Full 100%-to-0% AC discharge; load not specified. Recharge took 3.54 kWh from the wall. Measured UPS switchover: 8.25 ms. |
Specifications
| BLUETTI Apex 300 | EcoFlow DELTA 3 Ultra Plus | |
|---|---|---|
| Battery | ||
| Rated capacity | 2,764.8 Wh | 3,072 Wh |
| Tested usable capacity | 2,350 Wh (85%) | 2,610 Wh (85%) |
| Chemistry | LiFePO4 | LiFePO4 |
| Cycle life | 6,000 to 80% | - |
| Expandable | Yes, up to 19,353.6 Wh | Yes, up to 11,000 Wh |
| Output | ||
| AC output | 3,840 W (7,680 W surge) | 3,600 W (7,200 W surge) |
| Boost mode (resistive loads) | - | 4,600 W |
| AC outlets | 6 total | 5 total |
| 120V 20A outlets (NEMA 5-20R) | 4 | 4 |
| RV 30A outlet (TT-30R) | 1 | 1 |
| 120/240V 50A outlet (NEMA 14-50R) | 1 | - |
| AC waveform | Pure sine wave | Pure sine wave |
| USB-C ports | 0 | 3 (up to 140 W each) |
| USB-A ports | 0 | 1 |
| 12 V car outlet | No | Yes |
| DC5521 ports | 0 | 0 |
| UPS / pass-through | Yes (0 ms switchover) | Yes (10 ms switchover) |
| Charging | ||
| AC charging | 1,800 W | 1,800 W |
| Max solar input | 2,400 W | 1,600 W |
| Solar input voltage | 2 inputs, 12-60V, 20A each | 11-60V (2 inputs) |
| Car charging | 192 W | - |
| Build | ||
| Weight | 83.8 lb (38 kg) | 74.3 lb (33.7 kg) |
| Dimensions | 20.67 x 12.87 x 12.6 in | 613 x 328 x 395 mm |
| App | Wi-Fi + Bluetooth | EcoFlow app (Wi-Fi and Bluetooth) |
| Warranty | 5 years | 5 years |
| Released | 2025-08 | 2025-09 |