EcoFlow RIVER 3 Plus vs Anker 521 PowerHouse
Side-by-side on the specs that decide it — surge, capacity, runtime and price.
Both models' specs verified against manufacturer listings · Last updated
The short answer
Anker 521 PowerHouse costs $80 less. Whether that gap is worth closing depends on what you need to run.
- EcoFlow RIVER 3 Plus holds 12% more energy (286Wh vs 256Wh), so it runs the same load proportionally longer.
- EcoFlow RIVER 3 Plus has 900W more surge headroom (1200W vs 300W) — that decides whether a fridge, pump or AC compressor will actually start.
- Anker 521 PowerHouse is 1.7 lb lighter (8.2 lb vs 9.9 lb).
Neither of these will start a sump pump or well pump — both surge below the ~3,400W those motors need. If home backup with pumps is your use case, look at higher-surge models instead of either of these.
Doubles the River 3's output for $90 more, and adds an expansion battery port. The better buy of the two unless weight is everything.
Best for: Campers who want one unit that covers devices plus the occasional small appliance.
Where it falls short:
- 286Wh alone is a single evening of real use
- 220W solar input is modest
A pocket-scale LiFePO4 unit for keeping devices alive. 200W of output means it's a charger, not an appliance station.
Best for: Travelers and campers topping up phones, cameras and a laptop.
Where it falls short:
- 200W output runs devices only
- 256Wh is small
| Spec | EcoFlow RIVER 3 Plus | Anker 521 PowerHouse |
|---|---|---|
| Price | $329 | $249 |
| Capacity | 286 Wh | 256 Wh |
| Continuous output | 600 W | 200 W |
| Surge output | 1200 W | 300 W |
| Battery | LiFePO4 | LiFePO4 |
| Rated cycles | 3,000 | 3,000 |
| Weight (lighter wins) | 9.9 lb | 8.2 lb |
| Max solar | 220 W | 100 W |
| Recharge time (faster wins) | 1h | 2h 30m |
Runtime head-to-head
| Appliance | EcoFlow RIVER 3 Plus | Anker 521 PowerHouse |
|---|---|---|
| Refrigerator | 4.1 hrs | ❌ |
| Mini fridge | 7.7 hrs | ❌ |
| Chest freezer | 3.0 hrs | ❌ |
| CPAP machine | 6.1 hrs | 5.4 hrs |
| Sump pump | ❌ | ❌ |