Backup
Battery size for 1 day of essential loads
Essentials (fridge, freezer, CPAP, router, TV, sump pump, laptop, fan) use about 4.1 kWh a day. 1 day of backup needs a 5.04 kWh battery; recharging daily takes about 1,092 W of panels.
| Load | Wh/day | Basis |
|---|---|---|
| a full-size refrigerator | 912 | 38 W annual-average draw × 24 h |
| a chest freezer | 550 | 22.9 W annual-average draw × 24 h |
| a CPAP | 449 | 56.1 W × 8 h/day (assumed use) |
| a 55-inch TV | 384 | 76.9 W × 5 h/day (assumed use) |
| a sump pump | 1,116 | 1115.5 W × 1 h/day (assumed use) |
| a ceiling fan | 100 | 12.5 W × 8 h/day (assumed use) |
| a Wi-Fi router | 209 | 8.7 W × 24 h/day (assumed use) |
| a laptop | 360 | 60 W × 6 h/day (assumed use) |
| Total | 4,080 |
Shop this setup
As an Amazon Associate we earn from qualifying purchases.
5 kWh LiFePO4 home batteries400 W solar panelsHybrid invertersHome backup power stations
Questions
What battery size for 1 day of essentials?
Essentials (fridge, freezer, CPAP, router, TV, sump pump, laptop, fan) use about 4.1 kWh a day. 1 day of backup needs a 5.04 kWh battery; recharging daily takes about 1,092 W of panels.