1. What is Generator Wattage Calculation?

The generator wattage calculation determines the minimum power output required from a generator to safely run all your essential electrical loads during a power outage, with an appropriate safety margin.

2. How Does the Calculator Work?

The calculator uses the generator sizing formula:

Where:

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

Explanation: The safety factor ensures your generator can handle startup surges (which can be 2-3 times running wattage for some appliances) and provides capacity for future additions.

3. Importance of Proper Generator Sizing

Details: Proper sizing prevents generator overload (which can damage both generator and appliances) and ensures reliable power for essential circuits during outages.

4. Using the Calculator

Tips:

1. Calculate total wattage of all appliances you want to power simultaneously
2. Select appropriate safety factor (1.35 recommended for most homes)
3. The result shows the minimum generator size you should consider

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between running and starting watts?
A: Running watts are what an appliance uses continuously. Starting watts (surge) are the extra power needed briefly when motors start (2-3x running watts).

Q2: How do I calculate my total loads?
A: List all appliances you want to power, find their wattage (usually on nameplate), and sum them. For motors, use starting wattage in your calculation.

Q3: Why use a safety factor?
A: It accounts for: 1) potential underestimation of loads, 2) future additions, 3) reduced efficiency at high altitudes or temperatures, and 4) voltage drop over long wire runs.

Q4: What if my calculated wattage is between standard generator sizes?
A: Always round up to the next available size. It's better to have extra capacity than not enough.

Q5: Should I consider fuel type in this calculation?
A: No, but note that diesel generators typically handle heavy loads better than gasoline, while propane offers cleaner operation but slightly less power.