July 18, 2018
So, you’re tired of being left in the dark during an outage. You’re probably looking at your options for a whole-home generator so you’re not stuck without power anymore, right?
To determine what size generator you need to power your whole house:
We’ll walk you through the process in more detail below. Before we do that, let’s look at how generators are sized.
Need an electrician to calculate what size generator your home needs? Give us a call at (800) 226-2636 or schedule an appointment online.
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Generators are sized based on their electrical output, not their physical dimensions. They’re measured in watts (W) or kilowatts (kW), both of which are a measurement of electricity (1kW = 1,000W).
It’s important to get the right size generator.
Why, you ask? Well, if you get a generator that’s…
That being said, let’s look at how you can calculate what size generator your home needs.
To calculate what size generator you need to power your whole home, follow these 3 steps:
Step 1: List out every appliance you want to power.
Step 2: Determine the starting and running wattage of everything on your list. If you can’t find these numbers on the appliance label, you can use this wattage estimation guide as a reference.
Note: Starting wattage (also known as “surge wattage”) refers to the wattage an appliance needs at start-up. Starting wattage is normally 2–3 times higher than its “running” wattage, or how many watts an appliance needs to run constantly.
Step 3: Add the wattage together. Then, use this number to guide what size generator you need.
Keep in mind that a DIY wattage estimate is just that: an estimate. To be on the safe side, we recommend using a wattage calculator or, even better, having a professional electrician calculate the exact wattage you need to help you find the right size generator.
If you’re up for trying it yourself though, let’s look at a couple examples.
If you want to power just the “essentials”, your list might look something like this:
In this case, you’d need at least a 25kW generator, since the starting wattage is 24,100W.
If you want to power just about everything in your home, your list would probably look more like this one:
In this situation, you’d probably want at least a 35kW whole-home generator.
Learn more about our services and generators we install.