How to Estimate Solar Panel Output by Location
The solar panel output by location calculator helps you understand how much energy your solar system can produce based on solar irradiance (kWh/m²/day), panel wattage, efficiency, and number of panels. Because sunlight levels vary significantly across regions, knowing your local irradiance is the key to accurate solar power estimation.
1. What Is Solar Irradiance?
Solar irradiance measures the amount of sunlight energy hitting one square meter of surface per day, usually expressed in kWh/m²/day. For example, locations near the equator may receive 5–6 kWh/m²/day, while northern regions may average 3–4 kWh/m²/day. You can find typical irradiance values for your city using global solar maps or databases like Global Solar Atlas.
2. How to Calculate Daily and Yearly Solar Output
The calculator multiplies solar irradiance by your panel’s effective area and efficiency to estimate energy output per panel. It then scales the result by the total number of panels in your array to show daily and annual production.
For example, a 10-panel system using 400 W panels with 20% efficiency in a 5 kWh/m²/day location produces roughly:
- Daily: around 20 kWh/day
- Yearly: around 7,300 kWh/year
3. Why Location Makes a Big Difference
A solar system in Kuala Lumpur can generate nearly twice the output of the same setup in London due to higher average sunlight hours. Factors such as latitude, cloud cover, and seasonal variations all influence how much sunlight reaches your panels throughout the year.
4. Real-World Factors That Affect Solar Output
- Panel tilt and azimuth: Improper orientation can reduce performance by 10–25%.
- Temperature losses: Hotter environments slightly reduce solar panel efficiency.
- Shading and dirt: Partial shading or dust can cause significant losses if not mitigated.
- System losses: Wiring, inverter inefficiencies, and mismatch losses typically account for 10–15% reduction.
5. Improving Solar Output Accuracy
To refine your estimates, use location-specific data and consider tools such as:
- Daily kWh from Solar Panels Calculator
- Optimal tilt vs seasonal tilt calculator
- Dust & Soiling Loss Estimator
- Solar Irradiance Using Atlas
6. Conclusion
The Solar Panel Output by Location Calculator is an essential tool for homeowners, engineers, and solar designers. By entering local irradiance and panel specifications, you can quickly estimate realistic energy yields and compare performance across regions.
Remember: your actual output will depend on real-world conditions, but this tool gives you a solid baseline for planning your solar installation or off-grid system.