Solar Production Calculator
Estimate your solar panel energy output daily, monthly and yearly based on wattage, peak sun hours, and system efficiency instantly.
Solar Production Calculator
How to Use Solar Production Calculator
Accurately estimating solar energy production helps you determine whether a solar system meets your consumption requirements and assess its financial return. Follow these simple steps to calculate your solar output:
- Step 1: Enter panel wattage. Input the rated power output of each individual solar panel in Watts (e.g., 400 W). This value is found on the panel's datasheet or product label.
- Step 2: Enter number of panels. Input the total number of solar panels installed or planned for your system.
- Step 3: Enter peak sun hours. Specify the average daily peak sun hours for your location. This value typically ranges from 3 to 7 hours depending on your region and season.
- Step 4: Set system efficiency. Enter the overall system efficiency percentage (default 80%) to account for inverter losses, wiring resistance, temperature effects, and shading.
- Step 5: Click Calculate Solar Production. Press the button to run the calculation instantly.
- Step 6: Review your results. View daily energy output as the primary result, along with monthly output, annual output, and total system capacity displayed in the results panel.
How to Calculate Solar Energy Production
Solar energy production depends on your system's total capacity, the available sunlight at your location, and real-world efficiency losses. The calculation uses four straightforward formulas.
Basic Formulas
Step-by-Step Example
Given: 10 panels × 400 W each, 5 peak sun hours, 80% system efficiency
Step 1: Calculate System Capacity
400 W × 10 panels = 4,000 W ÷ 1,000 = 4.0 kW
Step 2: Calculate Daily Energy Output
4.0 kW × 5 hours × 0.80 = 16.0 kWh/day
Step 3: Calculate Monthly Output
16.0 kWh × 30 = 480 kWh/month
Step 4: Calculate Annual Output
16.0 kWh × 365 = 5,840 kWh/year
Practical Note: Actual production will vary seasonally. Use your location's annual average peak sun hours for the most accurate yearly estimate.
Quick Reference
- 5 panels × 400 W at 5 sun hours = ~8 kWh/day
- 10 panels × 400 W at 5 sun hours = ~16 kWh/day
- 20 panels × 400 W at 5 sun hours = ~32 kWh/day
Solar Production Output Reference Chart
Use this chart to quickly estimate daily, monthly, and annual energy output for systems of varying sizes. Calculations assume 400 W panels, 5 peak sun hours per day, and 80% system efficiency.
| Number of Panels | System Capacity | Daily Output | Monthly Output | Annual Output |
|---|---|---|---|---|
| 5 Panels | 2.0 kW | 8.0 kWh | 240 kWh | 2,920 kWh |
| 10 Panels | 4.0 kW | 16.0 kWh | 480 kWh | 5,840 kWh |
| 15 Panels | 6.0 kW | 24.0 kWh | 720 kWh | 8,760 kWh |
| 20 Panels | 8.0 kW | 32.0 kWh | 960 kWh | 11,680 kWh |
| 25 Panels | 10.0 kW | 40.0 kWh | 1,200 kWh | 14,600 kWh |
Production Note: Adjust peak sun hours for your specific region. Locations in the American Southwest average 6–7 hours while northern climates may average 3–4 hours, significantly affecting annual output totals.
Solar Production Frequently Asked Questions
A single 400 W solar panel in a location with 5 peak sun hours per day and 80% system efficiency produces approximately 1.6 kWh of usable energy per day (400 W × 5 hours × 0.80 = 1,600 Wh = 1.6 kWh). Output varies with location, shading, temperature, and panel orientation.
Peak sun hours represent the number of hours per day when solar irradiance averages 1,000 W per square meter — the standard test condition for solar panels. A location with 5 peak sun hours receives the equivalent energy of 5 hours of full-intensity sunshine, regardless of how many total daylight hours there are.
System efficiency accounts for real-world energy losses including inverter conversion losses, cable resistance, dust or shading on panels, temperature-related efficiency drops, and battery charging inefficiencies. A standard 80% efficiency factor ensures your production estimates reflect actual usable output rather than theoretical panel ratings.
Monthly solar energy production equals your daily output multiplied by 30. For example, a 4 kW system with 5 peak sun hours and 80% efficiency produces 16 kWh per day (4 × 5 × 0.80), which equals 480 kWh per month (16 × 30).
A typical residential solar system between 5 kW and 10 kW should produce 20 kWh to 50 kWh per day depending on location, sun hours, and system efficiency. In sunny climates with 5–6 peak sun hours, a 6 kW system at 80% efficiency generates approximately 24–29 kWh daily, covering most average household energy consumption.