1. What is Whole House Generator Wattage?

The total wattage required for a whole house generator is calculated by summing all electrical loads in the home and applying a safety factor (typically 1.2 to 1.5) to account for startup surges and future expansion.

2. How Does the Calculator Work?

The calculator uses the generator wattage formula:

Where:

• \( P_{total} \) — Required generator wattage (W)
• \( \sum P_{loads} \) — Sum of all connected electrical loads (W)
• 1.2 to 1.5 — Safety factor (accounts for startup surges)

Explanation: The safety factor ensures the generator can handle momentary startup surges (particularly for motors and compressors) and provides capacity for future additions.

3. Importance of Proper Sizing

Details: Proper generator sizing is crucial for reliable operation. Undersizing can lead to overloads and failure to start large appliances, while oversizing leads to inefficient operation and higher costs.

4. Using the Calculator

Tips:

• Calculate or estimate your total connected load (sum of all appliances and systems)
• Use 1.35 safety factor for typical residential applications
• Round up to the nearest standard generator size
• Consider future expansion when selecting safety factor

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between running watts and starting watts?
A: Running watts are continuous power needs, while starting watts are temporary surges (3-5x running watts) needed when motors start.

Q2: How do I calculate my total connected load?
A: Sum the wattage of all appliances you want to power simultaneously. Check appliance labels or manuals for wattage information.

Q3: What safety factor should I use?
A: 1.35 is typical for residential. Use 1.5 if you have many motor loads or plan future expansion.

Q4: Can I use this for commercial applications?
A: Commercial applications often require more detailed load analysis and professional calculation methods.

Q5: What are standard generator sizes?
A: Common residential sizes are 5kW, 7.5kW, 10kW, 12.5kW, 15kW, 20kW, and 25kW.