1. What is Solar Panel Wattage Calculation?

The solar panel wattage calculation estimates the power output of a solar panel system based on sunlight intensity, panel size, and efficiency. It helps determine how much electricity your solar panels can generate.

2. How Does the Calculator Work?

The calculator uses the solar power formula:

Where:

• \( P_{solar} \) — Solar power output (watts)
• \( I \) — Solar irradiance (W/m²)
• \( A \) — Panel area (m²)
• \( Eff \) — Panel efficiency (0 to 1, typically 0.15-0.22 for commercial panels)

Explanation: The equation calculates the theoretical maximum power output under ideal conditions. Real-world output may be 10-25% lower due to various factors.

3. Importance of Solar Power Calculation

Details: Accurate solar power estimation helps in sizing your solar system correctly, determining energy production potential, and calculating return on investment.

4. Using the Calculator

Tips:

• Standard test condition irradiance is 1000 W/m²
• Typical residential panel efficiency ranges from 15-22% (0.15-0.22)
• Average panel size is about 1.6-2 m² for residential panels

5. Frequently Asked Questions (FAQ)

Q1: What is typical solar irradiance in my area?
A: It varies by location. Average values range from 150-300 W/m² (annual average) depending on latitude and climate.

Q2: How does panel angle affect power output?
A: Optimal angle equals your latitude. Deviation from optimal angle reduces output by approximately the cosine of the angle difference.

Q3: What factors reduce real-world output?
A: Temperature effects (panels lose efficiency when hot), dirt, shading, wiring losses, and inverter efficiency all reduce output.

Q4: How many panels do I need for my home?
A: Divide your average daily kWh usage by (daily sun hours × panel wattage). Most homes need 20-30 panels.

Q5: What's the difference between STC and PTC ratings?
A: STC (Standard Test Conditions) is laboratory ideal, while PTC (PVUSA Test Conditions) is more realistic (typically 10-15% lower).