Home & DIY
Battery energy runtime
Estimate constant-load runtime after supplied usable-depth and efficiency factors.
A clear answer. Here’s how.
Delivered usable energy=nominal Wh×usable depth×efficiency. Runtime=delivered energy/load. Assumes a constant load and supplied overall usable fraction; does not infer capacity from chemistry or predict ageing, temperature effects, high-current losses, voltage cutoff or changing loads. Results are an energy-budget estimate rather than a discharge-curve simulation.
See a worked example
Worked example
A fixed demonstration, separate from the values you enter above.
- Nominal stored energy (Wh)
- 500
- Constant delivered load (W)
- 50
- Usable depth fraction (%)
- 80
- Delivery/conversion efficiency (%)
- 90
Example result
- Usable delivered energy (Wh)
- 360
- Runtime (hours)
- 7.2
- Runtime (days)
- 0.3