When your local power grid goes out, it can throw a real wrench in your plan. Without electricity, you can’t run your household lighting, security system, HVAC system, and all your electronic devices. Fortunately, a whole-home generator can be a great alternative that will power your home until your local power grid comes back on the map.

What Is a Whole-Home Generator?

Most people are fairly familiar with portable generators that can be used for activities like camping. However, there are larger standby generators that can be powerful enough to power the various systems in your home. This type of generator gets permanently installed outside your home.

Standby generators can run on one of a few different types of fuel. These include diesel, gasoline, propane, and natural gas. If you already have a natural gas line going to your home, then you can have an unlimited supply of fuel when you need it. If you opt for a standby generator that uses propane, gasoline, or diesel fuel, you’ll need to install an on-site storage tank to hold your fuel until you need it.

Generator Wattage

When it comes to determining the total output of a standby generator, manufacturers will list it on the package in the form of watts. Generators can range anywhere between 800 and 500,000 watts. When starting to determine the right generator for your home, it’s important to first determine the maximum wattage that you need. This will give you direct insight into what size generator your home will need to function appropriately.

Determine What You Want to Run

One of the best places to start is to determine what types of appliances and electronics you want to be able to run. Be sure to walk through all the rooms of your home so you don’t forget about potential items. Some common examples of items that you may want to be able to run include:

  • Refrigerator
  • Deep freezer
  • Washer
  • Dryer
  • Microwave
  • Oven
  • Coffee maker
  • Television
  • Lamps
  • Security system
  • HVAC system
  • Computer
  • Water Heater
  • Well Pump

Record Each Item’s Wattage

The next step of recording each item’s wattage can seem pretty simple at first. However, it’s important to note that items that have a motor, like many of your appliances, will have two wattages. These will be their running wattage and their starting wattage.

All of these items will require extra wattage when they start up to give their motors a much-needed jolt of energy to get going. This starting wattage is typically three times that of the item’s running wattage. For this reason, you’ll need to total the combination of the item’s running wattage and its starting wattage to reveal its total necessary wattage.

To get the wattage requirements of each item, refer to their manufacturer’s plate or tag. If you can’t find the right information, then refer to the item’s owner’s manual. Some examples of typical wattages include 1200 watts for a microwave, 150 watts for a lamp, and 600 watts for a coffee maker.

A Simple Example

To help you better understand how to calculate a prospective generator size, let’s take a look at a very simple example. Let’s say that you want to run a small refrigerator that has a running wattage of 350. The starting wattage will be three times that of the running wattage, so this would be 350 times 3.

This equals a starting wattage of 1,050. To get the total wattage, you need to add the starting wattage to the running wattage. This would be 1,050 plus 350, which equals a total wattage of 1,400. You’ll need a generator that can produce at least 1,400 watts of power to successfully run your small refrigerator when your home’s electricity goes out.

The 90% Rule

Ideally, it’s good practice to only use 90% of the generator’s total capacity. This means that your new generator should only be using up to 90% of its power when producing your necessary 1,400 watts. To figure out what 90% would be, you’ll want to take your maximum wattage of 1,400 and divide it by .90. Your system would need a total wattage of around 1,556.

Some generators may have their listing marked in kilowatts instead of watts. To get the kilowatt rating, it’s important to note that 1 kilowatt is equal to 1,000 watts. Your generator will need to be 1.55 kilowatts.

What Happens If You Get the Wrong Size Unit

If you don’t go through the process of getting precise measurements for all your appliances and electronic devices, you can end up with the wrong size generator. If the generator is too small, you’ll easily overload it whenever you attempt to run all your items. This will cause the generator to overheat and shut off.

In severe cases, it could lead to internal damage and even a fire. Conversely, if your generator is too large, you’ll end up spending way too much money to get it and operate it. It pays to have one of our electricians evaluate your electricity needs to ensure that you get the appropriate size of standby generator for your home.

In general, homes that want to run basic essentials, like their refrigerators and AC units, will need a 25kw generator. Homes that are looking to run items beyond the essentials, like their laptops and televisions, will need around a 35kw generator. Again, these are just roundabout estimates. You’ll always want to consult an electrician for a more precise determination.

Features Your Whole-Home Generator Should Have

Apart from ensuring that you get the appropriate size of generator for your home, there are some key features that you’ll want to ensure your new generator has. One of the most important is an automatic transfer switch or ATS for short. This switch is responsible for turning on whenever the power goes out to your home and turning off as soon as your power comes back on. This switch will ensure that your home still receives the power it needs even if you’re not home to turn your generator on when your electricity goes out.

Another thing to consider is the overall noise level of the unit. It’s important to note that all whole-home generators are installed outside of your home for fume dispersal and noise purposes. However, if you live in a tight neighborhood, you may be concerned with the overall operating noise of your standby generator. Choosing a low-noise unit can help to provide you with peace of mind about the noise level from your new generator.

Reliable Generator Installation Service

Green Dot Heating & Air offers reliable generator installation services to the Wilmington, NC community. We can assist with all your cooling, heating, electrical, blow-in insulation, HVAC zoning, ductwork, indoor air quality, smart thermostat, and whole-house fan needs. Call our office today to book your next consultation with one of our knowledgeable electricians.

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