The EcoFlow DELTA 3 Classic and the OUPES Mega 1 are evenly matched, rated 4.2 and 4.2. The EcoFlow DELTA 3 Classic leads on tested capacity. The OUPES Mega 1 wins on battery life, solar input and features. The EcoFlow DELTA 3 Classic costs $50 less ($499 vs $549).
A low-cost 1kWh LiFePO4 station for home backup and car camping where AC outlets are all you need. Pick the DELTA 3 Plus instead if you want 12V outputs, faster solar charging or an extra battery later.
Amazon $499A strong 1kWh home-backup station with a big inverter and room to expand, often sold well below list price on Amazon.
Amazon $549Prices 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.
Each factor is scored 0-100 against the same fixed reference points for every mid-size portable power station; a clear win is highlighted. How we rank explains each one.
| Factor weight | EcoFlow DELTA 3 Classic | OUPES Mega 1 |
|---|---|---|
| Overall rating | 4.2/5 | 4.2/5 |
| Value 25% | 82 $0.49 per rated Wh | 75 $0.54 per rated Wh |
| Tested capacity 15% | 81 88% of rated capacity delivered (2 tests) | 41 79% of rated capacity delivered (1 test) |
| Battery life 15% | 70 LiFePO4, 5-year warranty | 96 LiFePO4, 3,500 cycles, 5-year warranty |
| AC output 15% | 82 1,800 W continuous AC | 88 2,000 W continuous AC |
| Charging speed 10% | 95 0-100% on AC in 1 h | 96 0-100% on AC in 58 min |
| Portability 10% | 72 85 Wh per kg (26.7 lb (12.1 kg)) | 66 81 Wh per kg (27.8 lb (12.6 kg)) |
| Solar input 5% | 40 500 W max solar input | 74 800 W max solar input |
| Features 5% | 75 UPS (10 ms), 100 W USB-C, app | 100 UPS (20 ms), expandable, 100 W USB-C, app |
| Tested by | Usable AC energy | Of rated | Conditions |
|---|---|---|---|
| CNET | 947 Wh | 92.5% | 480W load logged with HOBOware; round-trip efficiency 81.34%; recharge from empty 55 min. |
| The Solar Lab | - | 83% | Inverter efficiency test (load not stated in the review). Measured AC recharge from empty just under 55 min. |
| Tested by | Usable AC energy | Of rated | Conditions |
|---|---|---|---|
| The Solar Lab | - | 79% | 1,779W appliance load ran for 27 minutes. |
| EcoFlow DELTA 3 Classic | OUPES Mega 1 | |
|---|---|---|
| Battery | ||
| Rated capacity | 1,024 Wh | 1,024 Wh |
| Tested usable capacity | 899 Wh (88%) | 809 Wh (79%) |
| Chemistry | LiFePO4 | LiFePO4 |
| Cycle life | - | 3,500 to 80% |
| Expandable | No | Yes, up to 5,120 Wh |
| Output | ||
| AC output | 1,800 W (3,600 W surge) | 2,000 W (4,500 W surge) |
| Boost mode (resistive loads) | 2,600 W | - |
| AC outlets | 3 total | 4 total |
| 120V 20A outlets (NEMA 5-20R) | 2 | 4 |
| 120V 2-prong outlets (NEMA 1-15R) | 1 | - |
| AC waveform | Pure sine wave | - |
| USB-C ports | 2 (up to 100 W each) | 2 (up to 100 W each) |
| USB-A ports | 1 | 4 |
| 12 V car outlet | No | Yes |
| DC5521 ports | 0 | 2 |
| UPS / pass-through | Yes (10 ms switchover) | Yes (20 ms switchover) |
| Charging | ||
| AC charging | 1,400 W | 1,400 W |
| Full AC charge time | 1 h (0-80% in 45 min) | 58 min (OUPES: full in 36 min with AC plus solar (2200W). The Amazon listing says 36 min to 80%. AC-only time not published) |
| Max solar input | 500 W | 800 W |
| Solar input voltage | - | 12-78V (MPPT 18-75V, 14A) |
| Car charging | 96 W | 96 W |
| Build | ||
| Weight | 26.7 lb (12.1 kg) | 27.8 lb (12.6 kg) |
| Dimensions | 398 x 200 x 283 mm | 15.1 x 9.1 x 11.6 in |
| App | EcoFlow app (Wi-Fi and Bluetooth) | OUPES app (Wi-Fi/Bluetooth) |
| Warranty | 5 years | 5 years |
| Released | 2025-09 | 2025-07 |
