Generator Sizing Worksheet

Generator Sizing Worksheet 

This generator worksheet will help you make generator sizing a simple process. You’ll need to write your answers down in order to properly calculate your power requirements.

Most light bulbs and modern appliances and devices have their wattage demands marked clearly on the device. In the event, you don’t see this vital information, refer to your owner’s manual.

If that’s not available, we suggest contacting the manufacturer. You can also acquire this information from a licensed electrician or a qualified generator reseller or dealer.

As a last resort, you can use this conversion formula. Take the amperage demands and multipy it time the volatage. Example, 2 amps times 120 volts equals 240 watts.

Amps x Volts = Watts

What Appliances, Devices and Tools Do You Want To Run and Why?

(Make a list of all of the appliances, etc., that you will be powering by your generator. Ask yourself the question, “why,” to help you determine if you really need that appliance, room or device during an emergency or power outage)

Do You Have Any Devices Such as Motor or Pumps That Require 240 Volts?
(If so, you will need a dual output 120 and 240 Volt Generator. Don’t assume all devices are 120 volts, check and confirm)

What is the Starting Wattage For Each Appliance, Device and Tool?

(This figure is the one you will use to determine your actual generator size)

What is the Running Wattage For Each Appliance, Device and Tool?

(You will use this figure if you have no devices such as motors or pumps that require a higher wattage at start up)

What is Your Total Wattage?

(You take your total start up wattage and add 20 to 25% and that figure is your total wattage)

Remember to consult a licensed electrician and/or a qualified generator specialist if you are unsure of these calculations. As we have repeatedly stated, generator sizing is the most important facet of choosing a generator. Get this process wrong and you will most likely experience one or more the symptoms related to generator under sizing: