Home battery payback
6 kWh home battery payback example
This worked example shows how simple payback changes with installed cost, cycling, round-trip efficiency and the value of each shifted kWh.
Illustrative base case15.6 years simple payback
£4,600 installed cost · 0.75 cycles/day · 90% efficiency · 20p/kWh value spread
Low / base / high-benefit sensitivity
| Scenario | Cost | Cycles | Efficiency | Spread | Useful shifted energy | Annual value | Payback |
|---|---|---|---|---|---|---|---|
| Cautious | £5,520 | 0.50/day | 88% | 12p | 964 kWh | £116/yr | 47.7 yrs |
| Base | £4,600 | 0.75/day | 90% | 20p | 1,478 kWh | £296/yr | 15.6 yrs |
| High-use / wide spread | £3,910 | 0.90/day | 92% | 28p | 1,813 kWh | £508/yr | 7.7 yrs |
The installed cost is a worked-example assumption, not a current quote. Battery degradation, usable capacity, warranty limits, financing, export effects and real control behaviour are excluded from simple payback.