Tool
Battery runtime explainer
Illustrative only — estimates hours of essentials backup from usable battery kWh and continuous load watts. Not a design certificate.
What a ~5 kWh usable pack typically covers
| Load | Approx. W | On essentials? |
|---|---|---|
| LED lights (several) | 40–100 | Yes |
| Wi-Fi / ONT | 10–20 | Yes |
| Fridge | 100–150 avg | Yes |
| TV + decoder | 80–150 | Often |
| Kettle / geyser / stove | 2000–3000+ | Usually no |
Heavy thermal loads belong on the grid or a much larger system — not a small backup board.