Fortress Power FP-Nano
The Fortress Power FP-Nano is a home battery range from Fortress Power with 18 models. Models store 20.48 kWh – 61.44 kWh in Lithium Iron Phosphate cells. Rated AC power 20.48 kW – 61.44 kW. Listed and verified: UL 1973 and UL 9540. Sold in United States.
Specifications
- Capacity
- 20.48 kWh – 61.44 kWh
- Battery chemistry
- Lithium Iron Phosphate
- Rated AC power
- 20.48 kW – 61.44 kW
- Models in this range
- 18
Backup and savings with the Fortress Power FP-Nano
From 20.48 kWh to 61.44 kWh of storage, the Fortress Power FP-Nano stores daytime solar for the evening and night, and with a backup-capable installation keeps a home running through a power cut. It delivers 20.48 kW of AC power (up to 61.44 kW in larger configurations), enough to run heat pumps, ovens and air conditioning alongside the rest of the house.
One full charge covers about 69% of an average US home's daily electricity use of 29.6 kWh.
Its LiFePO4 (lithium iron phosphate) cells are the long-life chemistry of home energy storage: rated for thousands of cycles and more thermally stable than other lithium-ion types.
| Load | Runs for about |
|---|---|
| Essential circuits: fridge, lights, internet, phone charging (about 500 W) | 37 hours |
| An average US home (about 1.23 kW around the clock) | 15 hours |
Estimates. Electricity prices: U.S. Energy Information Administration, average household electricity use.
Product details
- Product type
- Home battery
- Brand
- Fortress Power
- Category
- Home Battery Storage
- Sold in
- United States
- Listed in
- California Energy Commission
Models (18)
| Model | Nominal capacity | Usable capacity | AC power | Certificate |
|---|---|---|---|---|
| FP-Nano-S4-I | 20.48 kWh | 20.48 kVA | ||
| FP-Nano-S4-O | 20.48 kWh | 20.48 kVA | ||
| FP-Nano-S5-I | 25.6 kWh | 25.6 kVA | ||
| FP-Nano-S5-O | 25.6 kWh | 25.6 kVA | ||
| FP-Nano-S6-I | 30.72 kWh | 30.72 kVA | ||
| FP-Nano-S6-O | 30.72 kWh | 30.72 kVA | ||
| FP-Nano-S7-I | 35.84 kWh | 35.84 kVA | ||
| FP-Nano-S7-O | 35.84 kWh | 35.84 kVA | ||
| FP-Nano-S8-I | 40.96 kWh | 40.96 kVA | ||
| FP-Nano-S8-O | 40.96 kWh | 40.96 kVA | ||
| FP-Nano-S9-I | 46.08 kWh | 46.08 kVA | ||
| FP-Nano-S9-O | 46.08 kWh | 46.08 kVA | ||
| FP-Nano-S10-I | 51.2 kWh | 51.2 kVA | ||
| FP-Nano-S10-O | 51.2 kWh | 51.2 kVA | ||
| FP-Nano-S11-I | 56.32 kWh | 56.32 kVA | ||
| FP-Nano-S11-O | 56.32 kWh | 56.32 kVA | ||
| FP-Nano-S12-I | 61.44 kWh | 61.44 kVA | ||
| FP-Nano-S12-O | 61.44 kWh | 61.44 kVA |
Certifications
| Certification | Market | Status | Reference | Valid until |
|---|---|---|---|---|
| UL 1973 | United States and Canada | ✓ Verified 19 October 2026 | SGS | |
| UL 9540 | United States and Canada | ✓ Verified 19 October 2026 | SGS |