How To Size A Standby Generator?

Generators can be extremely helpful as they provide power during blackouts or in places with an unavailable power supply. Generators come in different types that have their own wattage and requirements. One of the most common types of generators is the whole-house generator. With this, many homeowners inquire about how to size a standby generator. This article has all you need to know regarding this question.

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What Are Whole-House Generators?

honeywell standby generators for a homeWhole-house generators are also called backup generators, standby generators, and on-demand generators. This equipment provides backup power for the house when natural disasters or man-made mistakes cause power outages. These generators work for extended outages. They can power an entire home, including all the appliances, devices, and even the air conditioner.

They are also frequently called emergency generators. These units are bulky and installed on your property. The good news is backup generators add a lot of value to your home. They are highly reliable, so you have peace of mind when you have them. The best part about them is you don’t have to intervene for them to work. They automatically turn on when power interruptions and outages happen. You do not have to switch it off, too, because they automatically do that as well.

Generators help keep your refrigerator running, so the food in it doesn’t spoil. They also support your security system, so you have non-stop security at all times. This is very helpful, especially during disasters. They can power all your appliances as if there isn’t a power outage.

Before you purchase and install a whole-house generator in your home, make sure it is the right size. The standby generators should have sufficient power for all your appliances, especially the power-hungry ones.


What Is Standby Generator Size?

Understanding how much power you need for your home is essential when buying a generator. Its sizes are reliant on its electrical output and not the physical dimensions. However, you still need to take note of the latter as you have to set aside some space for it on your property.

Watts or kilowatts (kW) are the units used to measure a generator’s electrical output. One kilowatt equals a thousand watts. Remember this when determining the size you need.

Many people often make errors when looking for the size they need. They underestimate the wattage needed and buy a generator that’s too small for their home. As a result, the generator becomes overloaded and is forced to provide more power it can give. This will only result in the generator overheating, which in turn automatically turns it off. This can also cause damage to the generator.

On the other hand, a generator that’s too large means you have to pay more for the unit to work. Therefore, it is best that you consult a professional to figure out the size you need before installing a standby generator.

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How To Size A Standby Generator?

image of a blackout depicting a home without a standby generator

A calculator is needed for this simple process. The first step is determining the devices you want to power across your home. Look into the manual of any big appliances to figure out the running wattage they need. This number needs to be multiplied by three. Take note of the starting wattage as well. Add all the devices’ wattage to get the total wattage you need for the generator.

It is also recommended that you understand the meaning of these wattages. Starting wattage is the initial high load required to start electrical appliances from a dead stop. Take note that some appliances need extremely high starting loads, such as motors and compressors. On the other hand, the running load is what’s needed to keep the appliance running after starting.

The formula is laid out as follows: (Starting wattage x three) + running wattage

For example, a refrigerator requires a starting wattage of 700 watts. You need to multiply this by three (2100 watts) to calculate its load on a generator. Once it is running, it consumes 300 watts, so its overall generator load is at 2400 watts.

The generator needs to meet this value to run a refrigerator. Do this for all appliances and devices at home so you can arrive at the total wattage you need for your generator. Moreover, remember that these are only the minimum. An ideal situation is to have some overhead to ensure the generator doesn’t overload and short out as a result.

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Do I Need Professional Help For My Generator Installation?

You might have thought about conducting a do-it-yourself project. However, it is a laborious task that might go wrong. One miscalculation can result in a generator overloading and shorting out. Therefore, it is highly recommended that you get a professional to help you.

A professional will ensure that all appliances and devices are accounted for before the generator installation. They will make sure that the wiring and installation process is done well. They will also guarantee that the installed generator operates as intended and can handle the load of all home appliances without issue.

Whole-house generators require maintenance. It is another reason hiring a professional is the best idea. They will make certain that your generator is in excellent condition and working as it should.

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A whole-house generator is a wise idea that requires proper implementation. You need to ensure that the wattage of all devices you want to be powered around your home is accounted for and included in the calculation. You need to confirm that the calculation is correct. If not, the newly-installed generator might short out. Hire a professional to do it for a stress-free process. You don’t have to worry about any complicated calculation or whether it will work or not. A professional can help you and do everything for you.

Call Tevis Energy For All Of Your Standby Generator Requirements

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When you need backup generator installation, tune-ups, replacement, and repair services, do not hesitate to call Tevis Energy. Our company is the leading provider of generator installation services in central Maryland and southern Pennsylvania. We have excellent service contractors on staff who are well-trained in the most modern ways of HVAC and generator techniques. Call or contact us online to learn more about whole-house generator installation. Let the experts in the industry answer all your generator queries and contact Tevis Energy today. We offer free, in-home estimates.

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