☀️ Solar Production Calculator for Solar & Energy
Estimate daily and annual array generation.
This free tool helps you turn project measurements into a practical planning estimate. Enter values in Vaelden’s interactive calculator, review the result, and confirm important assumptions against supplier data, measurements, codes or qualified advice before committing materials or money.
Open the Solar Production calculator →
How to calculate solar production
Method: Daily generation = array capacity × peak-sun hours × system efficiency
- Use installed DC array capacity, not the inverter label.
- Use a conservative annual-average peak-sun-hours figure for the site.
- Allow for temperature, orientation, shading, soiling, wiring and inverter losses.
Worked example
Using these planning inputs:
- Array size: 6.6 kW
- Peak sun hours: 4.2 h/day
- System yield: 80 %
Daily generation: 22.2 kWh
Reality check: Monthly production varies sharply. Validate investment decisions with a site-specific shade study and an accredited installer’s model.
Method status and references
Screening model. This peak-sun-hours model is intentionally simpler than a bankable site simulation. Use PVWatts or a qualified local design for weather, orientation, shading, temperature and inverter effects.
Before you calculate
Use consistent units and the best measured inputs available. Real materials, equipment, site conditions and tolerances can change the result. Vaelden shows planning estimates; regulated, structural, electrical, plumbing, pressure and other safety-critical work still requires appropriate local compliance and professional advice.