1. What is a Solar PV Sizing Calculator?

Definition: This calculator estimates the required size of a photovoltaic (PV) system based on your energy consumption, available sunlight, and system performance.

Purpose: It helps homeowners and solar professionals determine the appropriate solar panel system size for a given energy need.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{Size} \) — PV system size in kilowatt-peak (kWp)
• \( \text{Load} \) — Annual energy consumption (kWh/year)
• \( \text{Hours} \) — Annual peak sunlight hours (h/year)
• \( \text{PR} \) — Performance ratio (dimensionless, typically 0.75)

Explanation: The annual load is divided by the product of sunlight hours and performance ratio to determine the required system size.

3. Importance of Proper PV Sizing

Details: Correct sizing ensures optimal energy production, cost-effectiveness, and system longevity while meeting your energy needs.

4. Using the Calculator

Tips: Enter your annual energy consumption in kWh, local annual peak sunlight hours (default 1200), and performance ratio (default 0.75). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the performance ratio (PR)?
A: PR accounts for system losses (typically 0.75-0.85) including temperature, wiring, inverter, and soiling losses.

Q2: How do I find my annual sunlight hours?
A: Check solar maps for your location or consult local solar installers. Values typically range from 900-1800 h/year.

Q3: Should I include future energy needs?
A: Yes, consider potential increases in consumption (EV charging, etc.) when calculating your annual load.

Q4: Does this account for battery storage?
A: No, this calculates grid-tied systems. For off-grid systems, you'll need additional calculations for battery capacity.

Q5: How accurate is this estimate?
A: This provides a preliminary estimate. Professional site assessment is recommended for precise sizing.