Solar panel output estimator
Estimate annual and monthly solar generation from your own integrated solar resource, array capacity, orientation multiplier and separate loss assumptions.
Array capacity above 0 to 1 million kWp; calendar years 1900 to 2200. All 12 uniquely numbered months required in monthly mode. Resource daily average 0 to 24 equivalent sun hours; period totals at most 24 times the calendar days. Orientation multiplier 0 to 3; each loss 0 to 100%. Monthly row text up to 100,000 characters. JSON report, results CSV and 12-row monthly CSV. Enter an annual solar resource or all 12 monthly resources in the settings. Monthly rows are month number 1 to 12 and resource. Up to 1,000,000 characters. Review the settings before running.
Your result
How to use Solar panel output estimator
- Enter array nameplate capacity and the calendar year.
- Choose annual or all 12 monthly resources, their unit and whether values are period totals or daily averages.
- Enter a sourced tilt/orientation multiplier and inverter, temperature, shading and soiling losses.
- Review annual yield and the monthly table, then download the JSON report and CSV files.
Useful next steps
Bring your own solar resource
Enter peak sun hours or integrated irradiation in kWh/m². At the 1 kW/m² reference they have the same numerical value. Instantaneous irradiance in W/m² is not a period energy input. No weather dataset or location lookup is included.
Annual data has no seasonal profile
Annual-only data is allocated uniformly per calendar day, including leap day. Those monthly numbers are bookkeeping allocations, not seasonal forecasts. Enter all 12 monthly resources for a seasonal pattern, including zero for months with no resource.
Orientation and losses
Use orientation multiplier 1 if the resource already describes the panel plane. Otherwise supply a conversion multiplier; entering tilt and azimuth angles is not enough to calculate it here. Loss factors multiply rather than add. Enter 0 for an effect already included elsewhere. This simplified estimate does not reproduce PVWatts or model hourly temperature, clipping, snow or availability.