Skip to Content

What Size Generator Do I Need?

Power - by Joe Weber - updated on 9/20/2023

3 different sized generators

You want to get a generator for your house for when the power goes out due to a severe storm, power grid issues or a natural disaster. But there are so many options, which one do you get? Keep reading to learn how to determine what size generator you need to power your necessary home appliances when there is no power.

Why Is Having a Generator Important?

We've all been there. A strong storm rolls through and knocks out the power. You hope it's a quick outage but the power ends up being out for hours due to damage to substations, transformers and power lines.

Without a generator or any type of backup power, you would be left in the dark, trying not to open the fridge to keep things cool and scrambling to find something to do to fight the boredom.

With a generator, you could keep your essential appliances, like the refrigerator and air conditioner or furnace, running so you don't have to worry about your food going bad or being too hot or too cold for the health and safety of your family. Not to mention the TV to keep your boredom at bay until the power comes back on.

How to Determine What Size Generator You Need

It can be easy to get overwhelmed with information when trying to figure out just what size generator you need for your home. There are a lot of generator sizes available and if you get one that is too small, you won't be able to power all of the appliances you want to have access to when the power goes out. It can be stressful and it's very easy to overthink it.

But in reality, this process is very simple and should not be stressful.

Every electrical appliance requires a certain amount of energy (watts) to start and run. The way to calculate how much power you need out of your generation is to look at each appliance you want to run.

Every electrical appliance should have an energy usage sticker on it. If it doesn't, or it isn't easily accessible, you can look online for the starting and running watts for that appliance.

What you'll want to do is write down the starting watts and running watts of each appliance. Once you've jotted down all of the details of the appliances you want to run:

  1. Add up all of the starting watts for each of the appliances to see how many watts you require to start them all.
  2. Add the running watts together to get the total amount of running watts required to run those appliances.
  3. The total starting and running watts will be the minimum power output of the generator you should purchase.

Please see the chart below for an example.

Appliance Starting Watts Running Watts
Refrigerator 2200 700
12/HP Sump Pump 2200 1050
TV 0 500
Furnace 2350 800
Air Conditioning 4500 2500

Calculate Starting Watts:

Highest Starting Watts

4500 watts

Total Running Watts

5550 watts

Total Starting Watts Needed

11250 watts

*It's important to note that this chart is just an example and your actual power demands may be different.

If we use the example above, we can see that if we want to run all of the above equipment, we need a generator that produces at least 5550 running watts and 11,250 starting watts.

What Generators Are Available at Batteries Plus?

Batteries Plus carries a wide variety of Champion generators that will fit a multitude of different power demands.

  • The workhorse with the power to run all of the appliances we listed above, and a great home backup generator is the Champion 12,000-watt generator. With 15,000 starting watts and 12,000 running watts, this generator packs the power you need. It features an electric start, no more pulling a cable to crank the engine, making it the easiest generator to get running.
  • Don't want to have to run outside during the storm to start your generator? The 9375 starting-watt Champion 7,500-watt generator is the one for you. It features a remote start feature so you can start the generator from the comfort of your home, out of the elements.
  • With 6,900 starting watts and 5,500 running watts, the flexible Champion 5,500-watt generator features dual-fuel capabilities, allowing you to use gas or propane to power your generator.
  • Perfect for camping or RVing, the Champion 1,200-watt generator is small yet mighty. It has the power you need for those necessary camping trips and also features cold-start technology to help start it on those cold fall mornings.

Be sure to take a look at our generator page to see all of the great Champion generators we have to offer along with any generator accessories that you may need like protective covers, extension cords and more!

Are There Other Types of Backup Power?

If you are looking for backup power but don't want a gas generator you bet there are options for you too!

The line of Goal Zero Yeti Power Stations will provide you with the power you need, wherever you need it. Need to use it for home backup power? No problem. Want to take it with you on a road trip to have the power to charge your phone and your other electronic toys? Unplug it and take it with you.

The Yeti can be charged with a standard wall outlet or by using a Goal Zero solar panel to give you power wherever you are. No outlet, no problem. Be sure to check out all of the awesome Goal Zero solutions we have to offer on our Goal Zero Shop.

Stop into your nearest Batteries Plus store to talk to one of our in-store experts about our Champion generator and Goal Zero Yeti backup power solutions today!

Looking for backup power accessories and generators?

Shop Generators