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Calculators / Ecology / Solar energy offset
Solar energy offset calculator
Estimate annual solar production and household-use offset.
On this page
Estimated annual production11,680kWh
Use offset97.33%
Average daily production32kWh/day
Calculator controls
How to calculate
Estimate annual solar production and household-use offset.
annual production = capacity × peak-sun-hours × 365 × performance ratio
Worked example
Solar array capacity (kW): 8; Peak sun hours / day: 5; System performance (%): 80; Annual electricity use (kWh): 12000.
Estimated annual production: 11,680 kWh; Use offset: 97.33 %; Average daily production: 32 kWh/day.
Assumptions and limits
Shading, orientation, temperature, weather, degradation, inverter clipping, curtailment, and export rules affect results.
Results are rounded for display; calculations use unrounded values. Read our calculation methodology.
Understanding the result
Estimate annual solar production and household-use offset. Every assumption remains visible so the result can be checked or changed.
When this tool is useful
Use the solar energy offset for an initial estimate, comparison, or classroom calculation.
Understanding your inputs
| Input | What to enter |
|---|---|
| Solar array capacity (kW) | Enter a number of at least 0.000001 and no more than 1000000000000. |
| Peak sun hours / day | Enter a number of at least 0 and no more than 24. |
| System performance (%) | Enter a number of at least 0 and no more than 100. |
| Annual electricity use (kWh) | Enter a number of at least 0.000001 and no more than 1000000000000. |
Frequently asked questions
What are the limits of this solar energy offset?
Shading, orientation, temperature, weather, degradation, inverter clipping, curtailment, and export rules affect results.
Can I use different units?
Use the units printed beside each field. Convert measurements first when your source uses different units.