1. What is a Generator Size Calculator?

Definition: This calculator estimates the required generator size (in kW) to power a house based on the total electrical load and a safety factor.

Purpose: It helps homeowners and electricians determine the appropriate generator capacity for backup power needs.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Generator size (kilowatts)
• \( \Sigma P_{load} \) — Total electrical load (watts)
• \( SF \) — Safety factor (typically 1.25)

Explanation: The total wattage is converted to kilowatts (divided by 1000) then multiplied by a safety factor to account for startup surges and future needs.

3. Importance of Proper Generator Sizing

Details: Correct sizing ensures reliable power during outages while preventing generator overload, inefficiency, or damage to appliances.

4. Using the Calculator

Tips: Enter the total wattage of all appliances/lights you want to power simultaneously and a safety factor (default 1.25). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why do we need a safety factor?
A: The safety factor accounts for startup surges (especially for motors) and provides capacity for future electrical needs.

Q2: What's a typical safety factor?
A: 1.25 is common for residential use, but 1.5 may be needed for heavy motor loads or commercial applications.

Q3: How do I find my total electrical load?
A: Sum the wattage of all appliances/lights you want to run simultaneously, or use our Electrical Load Calculator.

Q4: Should I size for continuous or peak load?
A: The calculator handles both - the safety factor already accounts for peak/starting loads.

Q5: What if I have large motor loads (AC, fridge, etc.)?
A: Consider increasing the safety factor to 1.5 or using our Motor Load Generator Calculator for more precise sizing.