1. What is a Solar Power System Sizing Calculator?

Definition: This calculator estimates the required size of a solar power system based on annual energy consumption, peak sun hours, and system efficiency.

Purpose: It helps homeowners and businesses determine the appropriate solar panel system size for their energy needs.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{Size} \) — Solar system size (kilowatts)
• \( \text{Annual kWh} \) — Total annual electricity consumption (kilowatt-hours)
• \( \text{Peak Hours} \) — Average daily peak sun hours (typically 4-6 hours)
• \( \text{Efficiency} \) — System efficiency factor (0.7-0.85 typical)

Explanation: The formula divides annual consumption by the total available solar energy (adjusted for efficiency) to determine required system size.

3. Importance of Proper Solar System Sizing

Details: Correct sizing ensures optimal energy production, maximizes return on investment, and prevents over- or under-sizing of the solar array.

4. Using the Calculator

Tips: Enter your annual electricity usage in kWh, local peak sun hours (default 4.5), and system efficiency (default 0.75). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How do I find my annual kWh usage?
A: Check your electricity bills for total annual consumption or contact your utility provider.

Q2: What are peak sun hours?
A: The equivalent number of hours per day when solar irradiance averages 1,000 W/m². This varies by location.

Q3: Why is system efficiency less than 100%?
A: Efficiency accounts for losses from inverters, wiring, temperature, shading, and panel orientation.

Q4: Should I round up the calculated size?
A: Yes, it's common to round up to the nearest standard system size (e.g., 5kW, 7.5kW, 10kW).

Q5: Does this account for battery storage?
A: No, this calculates grid-tied system size. Add 20-30% for battery-based systems.