How to Calculate Solar Battery Storage

What is Solar Battery Storage?

Home solar battery storage captures excess solar generation during the day for use at night. Without a battery, excess solar is exported to the grid at low rates.

Step-by-Step Guide

1Battery saves money by shifting consumption from peak-tariff to off-peak periods
2Excess solar stored instead of exported at 5-15p/kWh, then used instead of buying at 24-30p/kWh
3Battery capacity: 5-15kWh for most homes; Tesla Powerwall: 13.5kWh

Worked Examples

Input

15kWh solar generation, 20kWh home use, 10kWh battery, 0.28 GBP/kWh import

Result

Battery stores approx 5kWh excess solar, saves approx 511 GBP/year

Frequently Asked Questions

What is Solar Battery Calc?

Home solar battery storage captures excess solar generation during the day for use at night. Without a battery, excess solar is exported to the grid at low rates

How accurate is the Solar Battery Calc calculator?

The calculator uses the standard published formula for solar battery calc. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Solar Battery Calc calculator use?

This calculator works with inches, kilowatts, watts. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Solar Battery Calc calculator use?

The calculator applies the standard formula for this type of calculation. See the 'How It Works' steps above for the detailed formula breakdown.

Ready to calculate? Try the free Solar Battery Storage Calculator

Try it yourself →