Anker SOLIX C300 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 SOLIX C300 costs $70 less. Whether that gap is worth closing depends on what you need to run.
- Anker SOLIX C300 holds 13% more energy (288Wh vs 256Wh), so it runs the same load proportionally longer.
- Anker SOLIX C300 has 300W more surge headroom (600W vs 300W) — that decides whether a fridge, pump or AC compressor will actually start.
- Anker 521 PowerHouse is 0.4 lb lighter (8.2 lb vs 8.6 lb).
We'd skip the Anker 521 PowerHouse in this matchup. It costs $70 more than the Anker SOLIX C300 while matching or trailing it on capacity, surge and cycle life — there's no spec here that justifies the premium.
Anker's smallest. 288Wh at $179 with three USB-C ports — aimed squarely at people charging modern devices, not running appliances.
Best for: Content creators and travelers with a bag full of USB-C gear.
Where it falls short:
- 300W output is device-only territory
- 100W solar input
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 | Anker SOLIX C300 | Anker 521 PowerHouse |
|---|---|---|
| Price | $179 | $249 |
| Capacity | 288 Wh | 256 Wh |
| Continuous output | 300 W | 200 W |
| Surge output | 600 W | 300 W |
| Battery | LiFePO4 | LiFePO4 |
| Rated cycles | 3,000 | 3,000 |
| Weight (lighter wins) | 8.6 lb | 8.2 lb |
| Max solar | 100 W | 100 W |
| Recharge time (faster wins) | 1h | 2h 30m |
Runtime head-to-head
| Appliance | Anker SOLIX C300 | Anker 521 PowerHouse |
|---|---|---|
| Refrigerator | ❌ | ❌ |
| Mini fridge | 7.8 hrs | ❌ |
| Chest freezer | ❌ | ❌ |
| CPAP machine | 6.1 hrs | 5.4 hrs |
| Sump pump | ❌ | ❌ |