Solar Panel and Battery Calculator

Calculation Formulas:

\[ \text{Panels} = \frac{\text{Load} \times \text{Hours}}{\text{Panel Output}} \] \[ \text{Battery} = \text{Load} \times \text{Days} \]

Load:

Daily Usage Hours:

Panel Output:

Days of Autonomy:

days

Panels Needed:

Battery Capacity:

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1. What is a Solar Panel and Battery Calculator?

Definition: This calculator estimates the number of solar panels and battery capacity needed based on your electrical load and usage patterns.

Purpose: It helps homeowners, businesses, and solar installers properly size solar power systems for optimal performance.

2. How Does the Calculator Work?

The calculator uses two main formulas:

\[ \text{Panels} = \frac{\text{Load} \times \text{Hours}}{\text{Panel Output}} \] \[ \text{Battery} = \text{Load} \times \text{Days} \times 24 \]

Where:

\( \text{Panels} \) — Number of solar panels needed
\( \text{Battery} \) — Battery capacity in watt-hours (Wh)
\( \text{Load} \) — Electrical load in watts (W)
\( \text{Hours} \) — Daily usage hours
\( \text{Panel Output} \) — Rated output of each panel (W)
\( \text{Days} \) — Days of autonomy (backup needed)

Explanation: The panel calculation determines how many panels are needed to meet daily energy needs, while the battery calculation determines storage requirements.

3. Importance of Proper Sizing

Details: Correct sizing ensures your solar system meets energy demands, maximizes efficiency, and prevents over- or under-investment in equipment.

4. Using the Calculator

Tips: Enter your electrical load in watts, daily usage hours, panel output (default 100W), and desired days of autonomy (default 1). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical panel output?
A: Residential panels are typically 250-400W, while smaller panels might be 100-200W. The default is set to 100W for conservative estimates.

Q2: How do I determine my electrical load?
A: Add up the wattage of all devices you'll power, or use our Load Calculator tool.

Q3: What are days of autonomy?
A: This is how many days you want backup power when there's no sunlight (cloudy days, etc.).

Q4: Does this include system losses?
A: No, consider adding 20-30% to account for inefficiencies in the system.

Q5: How do I convert battery Wh to Ah?
A: Divide Wh by battery voltage (e.g., for 12V: Wh ÷ 12V = Ah).