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Solar Panel Size Calculator

Panel Size Formula:

\[ \text{Panel Size} = \frac{\text{Power Needed}}{\text{Efficiency} \times \text{Irradiance}} \]

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(0-1)
W/m²

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1. What is a Solar Panel Size Calculator?

Definition: This calculator estimates the required solar panel area based on power needs, panel efficiency, and solar irradiance.

Purpose: It helps homeowners, engineers, and solar installers determine how much panel area is needed to meet specific power requirements.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \text{Panel Size} = \frac{\text{Power Needed}}{\text{Efficiency} \times \text{Irradiance}} \]

Where:

Explanation: The power requirement is divided by the product of efficiency and irradiance to determine the necessary panel area.

3. Importance of Solar Panel Sizing

Details: Proper sizing ensures your solar array meets energy needs, maximizes return on investment, and fits available installation space.

4. Using the Calculator

Tips: Enter your power needs in Watts, panel efficiency (default 0.18 for 18% efficient panels), and local irradiance (default 1000 W/m² for full sun). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is typical solar panel efficiency?
A: Most commercial panels range from 15-22% efficiency (0.15-0.22). Premium panels may reach 23-24%.

Q2: How do I find my local solar irradiance?
A: Check NASA's solar database or local meteorological data. Average values range from 800-1000 W/m² in sunny areas.

Q3: Should I account for system losses?
A: Yes, consider adding 10-25% to the calculated size to account for temperature effects, wiring losses, and degradation.

Q4: How does panel orientation affect this calculation?
A: This uses ideal conditions. Adjust irradiance value downward for non-optimal angles or partial shading.

Q5: Can I use this for off-grid systems?
A: Yes, but you'll need to calculate your total daily power needs and account for battery storage and days of autonomy.

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