1. What is a House Generator Size Calculator?

Definition: This calculator estimates the required generator size in kilowatts based on your 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)
• \( \sum P_{load} \) — Total electrical load (watts)
• \( SF \) — Safety factor (typically 1.25 for residential use)

Explanation: The total load in watts is converted to kilowatts (divided by 1000) then multiplied by a safety factor to ensure adequate capacity.

3. Importance of Proper Generator Sizing

Details: Correct generator sizing ensures reliable power during outages, prevents overload damage, and improves fuel efficiency.

4. Using the Calculator

Tips: Enter the total wattage of all appliances/equipment you want to power 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, future additions, and ensures the generator isn't constantly running at full capacity.

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

Q3: When would I change the safety factor?
A: Use higher factors (1.5-2.0) for heavy motor loads or commercial applications. Lower factors (1.1-1.2) may be acceptable for basic lighting circuits.

Q4: Does this include startup currents?
A: The safety factor helps cover startup surges, but for large motors you may need to calculate locked rotor current separately.

Q5: Should I round up the generator size?
A: Yes, always round up to the nearest standard generator size available in your market.