EcoFlow DELTA 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 $400 less. Whether that gap is worth closing depends on what you need to run.
- EcoFlow DELTA 3 holds 300% more energy (1024Wh vs 256Wh), so it runs the same load proportionally longer.
- EcoFlow DELTA 3 has 3300W more surge headroom (3600W vs 300W) — that decides whether a fridge, pump or AC compressor will actually start.
- Anker 521 PowerHouse is 20.5 lb lighter (8.2 lb vs 28.7 lb).
- EcoFlow DELTA 3 is rated for 4,000 cycles vs 3,000 — meaningful if you cycle it daily.
EcoFlow DELTA 3
The 1kWh class got a serious upgrade here. 3600W surge at $649 beats the older DELTA 2 on every axis that matters.
Best for: Anyone about to buy a DELTA 2 — this is the same money for materially better specs.
Where it falls short:
- Still only 1024Wh
- Solar input unchanged at 500W
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 3 | Anker 521 PowerHouse |
|---|---|---|
| Price | $649 | $249 |
| Capacity | 1024 Wh | 256 Wh |
| Continuous output | 1800 W | 200 W |
| Surge output | 3600 W | 300 W |
| Battery | LiFePO4 | LiFePO4 |
| Rated cycles | 4,000 | 3,000 |
| Weight (lighter wins) | 28.7 lb | 8.2 lb |
| Max solar | 500 W | 100 W |
| Recharge time (faster wins) | 56 min | 2h 30m |
Runtime head-to-head
| Appliance | EcoFlow DELTA 3 | Anker 521 PowerHouse |
|---|---|---|
| Refrigerator | 14.5 hrs | ❌ |
| Mini fridge | 27.6 hrs | ❌ |
| Chest freezer | 10.9 hrs | ❌ |
| CPAP machine | 21.8 hrs | 5.4 hrs |
| Sump pump | 1.1 hrs | ❌ |