1. What is a Solar Panel Size Calculator?

Definition: This calculator estimates the required solar panel size (in watts) based on your energy needs, available sunlight, and system performance.

Purpose: It helps homeowners, businesses, and solar installers determine the appropriate solar panel capacity for a given energy requirement.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P \) — Solar panel size (watts)
• \( Load \) — Daily energy requirement (watt-hours)
• \( H \) — Peak sunlight hours per day
• \( PR \) — Performance ratio (system efficiency)

Explanation: The energy requirement is divided by the product of sunlight hours and performance ratio to determine the panel wattage needed.

3. Importance of Solar Panel Sizing

Details: Proper sizing ensures your solar system meets energy needs without over-investing in unnecessary capacity, optimizing both performance and cost.

4. Using the Calculator

Tips: Enter your daily energy requirement in watt-hours, average peak sunlight hours (default 5), and performance ratio (default 0.75). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a performance ratio?
A: It accounts for system losses (typically 0.7-0.8) due to temperature, wiring, inverters, and other factors.

Q2: How do I find my daily energy requirement?
A: Sum the watt-hours of all devices you'll power, or check your electricity bill for daily kWh usage (multiply by 1000 to get Wh).

Q3: What are typical sunlight hours?
A: This varies by location (3-6 hours in most areas). Check solar maps for your region's average.

Q4: Should I round up the panel size?
A: Yes, it's recommended to round up to the nearest standard panel size and add 10-20% buffer for cloudy days.

Q5: Does this account for battery storage?
A: No, this calculates panel size only. Battery requirements depend on your need for nighttime power.