OUPES Mega 3
#5 in Home backupFull review
A big home-backup station with a 3600W inverter, RV outlet and massive solar input, for households that want to run large appliances through outages.
OUPES $1,199$1,199
The OUPES Mega 3 is the better portable power station overall, rated 4.0 to 3.7. The OUPES Mega 3 leads on value, battery life and solar input. The EcoFlow DELTA 3 Ultra Plus wins on portability. The OUPES Mega 3 costs $400 less ($1,199 vs $1,599).
EcoFlow DELTA 3 Ultra Plus
#20 in Home backupFull review
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 $1,599 EcoFlow $1,599$1,599
Prices were last checked October 20, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the OUPES Mega 3 for value ($0.39 per rated Wh vs $0.52 per rated Wh), battery life (LiFePO4, 3,500 cycles, 5-year warranty vs LiFePO4, 5-year warranty) and solar input (2,100 W max solar input vs 1,600 W max solar input).
- Choose the EcoFlow DELTA 3 Ultra Plus for portability (91 Wh per kg (74.3 lb (33.7 kg)) vs 81 Wh per kg (83.3 lb (37.8 kg))).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every home backup portable power station; a clear win is highlighted. How we rank explains each one.
| Factor weight | OUPES Mega 3 | EcoFlow DELTA 3 Ultra Plus |
|---|---|---|
| Overall rating | 4.0/5 | 3.7/5 |
| Value 25% | 86 $0.39 per rated Wh | 66 $0.52 per rated Wh |
| Tested capacity 15% | 73 86% of rated capacity delivered (1 test) | 68 85% of rated capacity delivered (1 test) |
| Battery life 15% | 96 LiFePO4, 3,500 cycles, 5-year warranty | 70 LiFePO4, 5-year warranty |
| AC output 15% | 37 3,600 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% | 66 81 Wh per kg (83.3 lb (37.8 kg)) | 84 91 Wh per kg (74.3 lb (33.7 kg)) |
| Solar input 5% | 63 2,100 W max solar input | 44 1,600 W max solar input |
| Features 5% | 100 UPS (20 ms), expandable, 100 W USB-C, app | 100 UPS (10 ms), expandable, 140 W USB-C, app |
Independent capacity tests
OUPES Mega 3
| Tested by | Usable AC energy | Of rated | Conditions |
|---|---|---|---|
| The Solar Lab | - | 86% | 2,968W appliance load ran for 53.5 minutes. The article states 3,720Wh capacity in one place; the runtime math matches the rated 3,072Wh. |
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
| OUPES Mega 3 | EcoFlow DELTA 3 Ultra Plus | |
|---|---|---|
| Battery | ||
| Rated capacity | 3,072 Wh | 3,072 Wh |
| Tested usable capacity | 2,642 Wh (86%) | 2,610 Wh (85%) |
| Chemistry | LiFePO4 | LiFePO4 |
| Cycle life | 3,500 to 80% | - |
| Expandable | Yes, up to 15,360 Wh | Yes, up to 11,000 Wh |
| Output | ||
| AC output | 3,600 W (7,000 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) | 5 | 4 |
| RV 30A outlet (TT-30R) | 1 | 1 |
| USB-C ports | 2 (up to 100 W each) | 3 (up to 140 W each) |
| USB-A ports | 4 | 1 |
| 12 V car outlet | Yes | Yes |
| DC5521 ports | 2 | - |
| UPS / pass-through | Yes (20 ms switchover) | Yes (10 ms switchover) |
| Charging | ||
| AC charging | 1,800 W | 1,800 W |
| Max solar input | 2,100 W | 1,600 W |
| Solar input voltage | 12-148V (MPPT 18-140V, 15A) | 11-60V (2 inputs) |
| Build | ||
| Weight | 83.3 lb (37.8 kg) | 74.3 lb (33.7 kg) |
| Dimensions | 25.2 x 11.9 x 17.2 in | 613 x 328 x 395 mm |
| App | OUPES app (Wi-Fi/Bluetooth) | EcoFlow app (Wi-Fi and Bluetooth) |
| Warranty | 5 years | 5 years |