1. What is an Online Solar System Calculator?

Definition: This calculator estimates the required solar system 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 system size for specific energy requirements.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P \) — Solar system power (watts)
• \( Load \) — Daily energy requirement (watt-hours)
• \( H \) — Average sunlight hours per day
• \( PR \) — Performance ratio (system efficiency, 0-1)

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

3. Importance of Solar System Sizing

Details: Proper sizing ensures your solar system meets energy needs without over-investment in unnecessary capacity, while accounting for real-world efficiency losses.

4. Using the Calculator

Tips: Enter your daily energy needs in watt-hours, average sunlight hours (default 5), and performance ratio (default 0.75). All values must be > 0, with PR ≤ 1.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine my daily energy load?
A: Check your electricity bills for kWh usage and convert to Wh (multiply by 1000), then divide by 30 for daily average.

Q2: What's a typical performance ratio?
A: Most systems have PR between 0.7-0.85, accounting for temperature, dirt, wiring, and inverter losses.

Q3: How do I find sunlight hours for my location?
A: Use solar maps or databases like NASA's or NREL's for your specific location's averages.

Q4: Does this include battery storage?
A: No, this calculates panel size only. Battery sizing requires additional calculations for autonomy days.

Q5: Should I add a safety margin?
A: Yes, consider adding 10-20% to account for future needs or reduced panel efficiency over time.