When to use this calculator
Estimate solar energy from rated capacity, equivalent full-sun hours and a system factor. Peak sun hours are an energy-equivalent assumption, not daylight hours. This is not a site-specific forecast.
Explore the solar generation & value calculators for other questions in this topic. For a related calculation, use the Solar Panel Count Calculator: Convert a nominal solar-array power target into whole panel count.
PUTTING IT INTO PRACTICE
Solar Output: a worked example
The values below are an illustrative example, not a recommendation. Replace them with measurements or assumptions that match your question.
| Input | Example value |
|---|---|
| System rating (kW) | 5 |
| Peak sun hours per day | 4 |
| System performance factor (%) | 80 |
| Days (integer) | 30 |
| Result | 480 kWh |
- Check the input labels and enter the example values above.
- Apply the relationship: Energy = rated kW × peak sun hours × factor/100 × days.
- The result is 480 kWh, rounded for display.
How to interpret your result
Peak sun hours are an energy-equivalent assumption, not daylight hours. This is not a site-specific forecast.
Peak sun hours describe equivalent full-power sunlight, not total daylight. Self-consumption and self-sufficiency have different denominators. On-site use and exports may have different monetary values.
Frequently asked questions
Are self-consumption and self-sufficiency the same percentage?
No. Self-consumption divides solar used on site by solar generated; self-sufficiency divides solar supplying demand by total site demand.
How do I use the solar output calculator?
Enter system rating (kw), peak sun hours per day, system performance factor (%), days (integer). The result updates automatically. Use the units shown beside each input; the example values illustrate the method.
Which formula does this calculator use?
Energy = rated kW × peak sun hours × factor/100 × days.
What should I check before using the result?
Peak sun hours are an energy-equivalent assumption, not daylight hours. This is not a site-specific forecast.
How are results rounded?
Scalar numbers display up to six decimal places, with scientific notation for very large or small values. Text, fraction, date and schedule outputs use the format described on the tool. Intermediate calculations use JavaScript floating-point arithmetic. Keep sensible precision for your measurements.
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