This tool helps you evaluate the profitability of installing a battery to store your excess electricity instead of selling it back to the grid. Modify any value (such as battery price or capacity) to automatically trigger the calculations and display the charts.

Parameters

Day cycle
Night cycle

Results

Usable capacity: -
Total storable energy: -
Cost per kWh stored: -
Effective day cycles: -
Effective night cycles: -
Total cycles per year: -
Energy stored per year: -
Annual sales loss: -
Annual purchase savings: -
Net annual gain: -
Payback time: -
Estimated lifespan: -

Payback over time

Cost comparison (€/kWh)

Explanation

This calculator helps you evaluate the economic benefit of installing a battery to store your excess electricity rather than selling it back to the grid.

The day and night cycles can be configured separately:

  • For each cycle, you define the percentage of capacity used (0-100%)
  • You also indicate how many days per year this cycle is used (1-365)
  • Default: day cycle at 90% for 300 days, night cycle at 50% for 330 days

The cost per kWh stored is the actual price it costs you for each kWh stored in the battery over its entire lifetime.

The net annual gain represents the savings made by storing energy instead of selling it and then buying it back later.

The payback time indicates the time required for the savings to offset the initial investment.

For the battery to be profitable, the payback time must be less than the estimated lifetime of the battery.