Solar Self-Consumption Calculator
Solar self-consumption measures how much generated solar electricity is used on site. Solar self-sufficiency measures how much of the site’s total electricity demand was supplied by that solar energy.
How to use this calculator
- Enter generation, self-used solar and total on-site load for the same period.
- Check that all inputs use the same units, period and population scope.
- Change one assumption at a time when comparing scenarios.
Formula used by solar self consumption rate calculator
Self-consumption = on-site-used solar ÷ solar generation × 100%; self-sufficiency = on-site-used solar ÷ total load × 100%.
- Self-consumption = on-site-used solar ÷ solar generation × 100%; self-sufficiency = on-site-used solar ÷ total load × 100%.
- Meter intervals, storage losses, inverter readings and grid charging can affect the energy boundaries. Use matching periods and avoid double-counting battery flows.
- The tool validates inputs and rounds displayed figures for readability; it does not validate assumptions against external records.
Worked examples
Worked example
Of 520 kWh solar generation, 338 kWh is used on site and total load is 610 kWh.
Self-consumption = 65%; self-sufficiency ≈ 55.41%.
The site uses 65% of its solar generation and solar supplies about 55.41% of its load.
Understanding the result
Solar self-consumption measures how much generated solar electricity is used on site. Solar self-sufficiency measures how much of the site’s total electricity demand was supplied by that solar energy.
Meter intervals, storage losses, inverter readings and grid charging can affect the energy boundaries. Use matching periods and avoid double-counting battery flows.
Important notes
Meter intervals, storage losses, inverter readings and grid charging can affect the energy boundaries. Use matching periods and avoid double-counting battery flows.
Treat the result as an estimate from the entered assumptions. For commercial, statistical, engineering or health-related decisions, verify relevant specifications and professional guidance.
Frequently asked questions
Can self-consumption exceed 100%?
Not when self-used solar is correctly measured as a subset of generation; the calculator rejects it.
Is high self-consumption the same as lowest energy bill?
Not necessarily; tariffs, export payments, storage costs and timing also influence cost.
How should I interpret this result?
Meter intervals, storage losses, inverter readings and grid charging can affect the energy boundaries. Use matching periods and avoid double-counting battery flows.
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Learn the method behind the number or compare the terminology before using the calculator.
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This page provides a calculation tool plus explanatory information so you can understand what the result means and when the underlying method may not fit your situation.