What is Solar Panel Production Estimator?
The Solar Production Estimator calculates the monthly energy output of a photovoltaic (PV) system. It combines the system's rated capacity (in kW) with local environmental data (Peak Sun Hours) to project energy generation in kilowatt-hours (kWh).
How it Works
1. Determine System Size (kW). 2. Input Peak Sun Hours. 3. Apply Efficiency Factor (derating).
Formula: $Monthly kWh = System kW \times Sun Hours \times 30 \times Efficiency$.
Standard efficiency derating (0.75-0.85) accounts for heat, wiring loss, and inverter inefficiency.
Step-by-Step Guide
- 1 System Size
- Total rating of all panels (e.g., 5kW).
- 2 Sun Hours
- Average daily hours of full sun intensity (not just daylight).
- 3 Derating
- Adjust for real-world losses (default ~80%).
- 4 Result
- Estimated monthly generation.
Example
Input: 5kW System, 4 Peak Hours
Result: 600 kWh/mo (approx)
FAQ
What are Peak Sun Hours?
An hour where sunlight intensity averages 1,000 watts per square meter. It is less than total daylight hours.
Does temperature affect output?
Yes, solar panels are less efficient in extreme heat.
How many panels do I need?
Divide your monthly usage by (Peak Sun Hours * 30 * Panel Wattage).
Grid-tied vs Off-grid?
This calc applies to both, but storage needs differ for off-grid.
Winter production?
Expect 30-50% less production in winter due to sun angle and shorter days.
Conclusion
Solar production varies significantly by season and location. This estimate helps you size your system correctly to offset your electricity bill. Always consult local installers for precise shading analysis.