EcoFlow DELTA Pro 3 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 $3450 less. Whether that gap is worth closing depends on what you need to run.
- EcoFlow DELTA Pro 3 holds 1500% more energy (4096Wh vs 256Wh), so it runs the same load proportionally longer.
- EcoFlow DELTA Pro 3 has 7700W more surge headroom (8000W vs 300W) — that decides whether a fridge, pump or AC compressor will actually start.
- Anker 521 PowerHouse is 104.8 lb lighter (8.2 lb vs 113 lb).
- EcoFlow DELTA Pro 3 is rated for 4,000 cycles vs 3,000 — meaningful if you cycle it daily.
EcoFlow DELTA Pro 3
The most complete large unit here. 4096Wh, 4000W, 8000W surge and 2600W of solar — it does everything the F3800 does with less weight.
Best for: Whole-home backup buyers who want maximum solar recharge speed.
Where it falls short:
- $3,699 is a serious investment
- Overkill unless you're backing up a whole home
Anker 521 PowerHouse
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 DELTA Pro 3 | Anker 521 PowerHouse |
|---|---|---|
| Price | $3699 | $249 |
| Capacity | 4096 Wh | 256 Wh |
| Continuous output | 4000 W | 200 W |
| Surge output | 8000 W | 300 W |
| Battery | LiFePO4 | LiFePO4 |
| Rated cycles | 4,000 | 3,000 |
| Weight (lighter wins) | 113 lb | 8.2 lb |
| Max solar | 2600 W | 100 W |
| Recharge time (faster wins) | 1h 40m | 2h 30m |
Runtime head-to-head
| Appliance | EcoFlow DELTA Pro 3 | Anker 521 PowerHouse |
|---|---|---|
| Refrigerator | 58.0 hrs | ❌ |
| Mini fridge | 110.5 hrs | ❌ |
| Chest freezer | 43.5 hrs | ❌ |
| CPAP machine | 87.0 hrs | 5.4 hrs |
| Sump pump | 4.4 hrs | ❌ |