How To Size A Standby Generator?

generac generator home and standby generator sizing

Generators can be used to meet your power needs during blackouts or in areas where power supply may not be available. There are various types of generators, each with its own wattage and requirements. Whole-home generators are one of the most common types. With this, many homeowners ask us “How to size a standby generator?”. In this article, we provide the answer to this question.

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What Are Whole-House Generators?

Also known as on-demand generators, backup generators, or standby generators, whole-house generators provide backup for the entire home in case of power outages, be they man-made errors or natural disasters. These generators are ideal for prolonged outages. They will power your entire home, including all the devices and appliances you have — the air conditioner, too!

They are also often referred to as emergency generators. These units are big and are installed on the property of your home. However, backup generators add a whole lot of value to your home. Since they are so reliable, they provide peace of mind. The best part is they do not require any human intervention. They work automatically, turning on during interruptions and outages. You do not have to turn it off either; that is wholly automatic as well.

These generators can power your refrigerator, preventing your food from spoiling. Your security system is supported as well. This ensures you always have non-stop security available; it is especially helpful during disasters. They can power all of your appliances in the same manner that you do when there isn’t a power outage.

However, before you go and get one installed in your home, you need to ensure you get the right standby generator size. The whole house generator must have enough power to run all your appliances, particularly the power-hungry ones.

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What Is Standby Generator Size?

Buying a generator requires understanding the amount of power you need to run your home. Sizes of generators are based on their electrical output. It is not the physical dimensions of the generator, though you will need to put aside some space for it on your property.

Electrical output is measured in watts or kilowatts (kW). One kilowatt is a thousand watts, so keep that in mind when figuring out the size.

Many people make mistakes when figuring out what size they need. They often underestimate the wattage they require, buying a generator that is too small to fit their needs. It is when the generator is overloaded and forced to supply more power than it can handle. You do not want this to happen as it will overheat the generator and automatically turn it off. It may also damage the generator. As for generators that are too large, you will end up paying more to operate the unit. Therefore, it is vital to consult with a professional to determine the power size before your standby generator installation.


How To Size A Standby Generator?

The process is quite simple. You will need a calculator for this one. First of all, identify the devices you want to power throughout your home. For the big ones, bring out the manual that came with the appliance to figure out how much running wattage they require. This has to be multiplied by three. You will also need to note down the starting wattage. Add up all the devices, and you will get the total wattage required for the generator.

Before going any further, you need to understand what these wattages mean. Starting wattage is the initial high load needed to start electrical appliances from a dead stop. Remember that some appliances may have very high starting loads, including compressors and motors. As for running load, it is the load needed to keep the device running after the initial start.

So, the formula can be laid out like the following.

(Starting wattage times three) plus running wattage

For example, a refrigerator may have a starting wattage of 700 watts. This means you have to multiply it by three to calculate the load on your generator (2100 watts). Once it starts running, it will consume 300 watts. So, the total load on your generator will be 2400 watts.

Your generator has to meet the above value to run a refrigerator. You will need to do this for all your appliances and electrical devices to figure out the total wattage needed for your generator. Also keep in mind that these are minimum numbers, so it is a good idea to keep some overhead to keep the generator from being overloaded and shorting out as a result.

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Do I Need Professional Help?

The thought of doing it yourself may have crossed your mind. However, it is a time-consuming task that may go wrong. Making one miscalculation will end in your generator shorting out due to overload. This is why it is a good idea to take professional help.

Hiring a professional will make sure all your appliances and electrical devices are accounted for before the installation of the generator. A professional will also ensure that all wiring and installation is done properly. They will make certain that the installed generator works as intended and can handle the load of all your appliances without a hitch.

Your whole house generator will also need maintenance, which is why hiring a professional is the best idea. They can ensure that your generator is in tiptop condition and is working as intended.

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In conclusion, a whole house generator is a good idea that needs proper execution. You need to make sure you calculate the wattage of all the devices you want to be powered throughout your home. You must confirm that your calculation is correct; otherwise, your newly installed generator may burn out. Hiring a professional to do it for you will result in a stress-free process. You need not worry about complex calculations and worrying about whether it will work or not. The professional will do it for you.

Call Townsend Energy For All Of Your Standby Generator Requirements

te logoTownsend Energy is a leading provider of generator installation services throughout New England. Not only do we offer backup generator installation, but also maintenance, replacement, and repair services. We only employ top quality service contractors who are well trained in the most modern methods of HVAC and generator techniques. Therefore, call or contact Townsend Energy online today for more information on a whole-house generator installation today. We offer free, in-home estimates.

Contact us today to have all of your generator questions answered by experts in the industry.

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