EcoFlow DELTA 3 Max 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 $1050 less. Whether that gap is worth closing depends on what you need to run.
- EcoFlow DELTA 3 Max Plus holds 700% more energy (2048Wh vs 256Wh), so it runs the same load proportionally longer.
- EcoFlow DELTA 3 Max Plus has 5700W more surge headroom (6000W vs 300W) — that decides whether a fridge, pump or AC compressor will actually start.
- Anker 521 PowerHouse is 49.1 lb lighter (8.2 lb vs 57.3 lb).
- EcoFlow DELTA 3 Max Plus is rated for 4,000 cycles vs 3,000 — meaningful if you cycle it daily.
EcoFlow DELTA 3 Max Plus
Adds 600W of continuous output and doubles surge headroom over the standard Max, for $200. Worth it only if you're running heavy loads.
Best for: Workshops and job sites where tool startup surge is the constraint.
Where it falls short:
- $200 premium is wasted if your loads are under 2400W
- 57 lb
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 Max Plus | Anker 521 PowerHouse |
|---|---|---|
| Price | $1299 | $249 |
| Capacity | 2048 Wh | 256 Wh |
| Continuous output | 3000 W | 200 W |
| Surge output | 6000 W | 300 W |
| Battery | LiFePO4 | LiFePO4 |
| Rated cycles | 4,000 | 3,000 |
| Weight (lighter wins) | 57.3 lb | 8.2 lb |
| Max solar | 1000 W | 100 W |
| Recharge time (faster wins) | 1h 22m | 2h 30m |
Runtime head-to-head
| Appliance | EcoFlow DELTA 3 Max Plus | Anker 521 PowerHouse |
|---|---|---|
| Refrigerator | 29.0 hrs | ❌ |
| Mini fridge | 55.3 hrs | ❌ |
| Chest freezer | 21.8 hrs | ❌ |
| CPAP machine | 43.5 hrs | 5.4 hrs |
| Sump pump | 2.2 hrs | ❌ |