EcoFlow DELTA 2 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 $650 less. Whether that gap is worth closing depends on what you need to run.
- EcoFlow DELTA 2 holds 300% more energy (1024Wh vs 256Wh), so it runs the same load proportionally longer.
- EcoFlow DELTA 2 has 1900W more surge headroom (2200W vs 300W) — that decides whether a fridge, pump or AC compressor will actually start.
- Anker 521 PowerHouse is 18.8 lb lighter (8.2 lb vs 27 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.
The value pick in the 1kWh class. Cheaper than the Anker C1000 with nearly identical capacity — but check the surge number before you buy.
Best for: Budget-conscious buyers running electronics and a fridge, with no motor-driven loads.
Where it falls short:
- X-Boost tops out at 2200W — the least surge headroom of any 1kWh unit we list
- 80-minute recharge is slower than Anker's 58
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 2 | Anker 521 PowerHouse |
|---|---|---|
| Price | $899 | $249 |
| Capacity | 1024 Wh | 256 Wh |
| Continuous output | 1800 W | 200 W |
| Surge output | 2200 W | 300 W |
| Battery | LiFePO4 | LiFePO4 |
| Rated cycles | 3,000 | 3,000 |
| Weight (lighter wins) | 27 lb | 8.2 lb |
| Max solar | 500 W | 100 W |
| Recharge time (faster wins) | 1h 20m | 2h 30m |
Runtime head-to-head
| Appliance | EcoFlow DELTA 2 | 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 | ❌ | ❌ |