Backup Generator Sizing

Backup Generator Sizing

How to Determine the Right Size Engine or Generator

While there is no substitute for having a certified electrician perform an inspection and calculate everything for you, the guidelines below do offer some great starting points and should at least get you started in the right direction.

What Size Generator Do I need? Watch this video.


Planning For A Home Backup Power System

Many people believe smaller generators can be used for standby electric power because they are not running all the time. This is not only a myth but can actually be very detrimental. Unfortunately, generator under sizing is one of the most common mistakes committed by buyers.  Not only does it involve the risks of damaging your new asset (the generator), but it can also damage other assets connected to it, create hazardous situations, and even limit overall productivity of the unit and/or the business relying on it.  If nothing else, the key thing to remember here is that more is always better than less.  

Getting a generator that can handle all your power generation needs is one of the most critical aspects of the purchasing decision.  Whether you are interested in prime or standby power, if your new generator can’t meet your specific requirements then it simply won’t be doing anyone any good because it can put undue stress on the unit and even damage some of the devices connected to it.  Unfortunately, determining exactly what size of generator to get is often very difficult and involves a number of factors and considerations. 

Although the following sizing guide will give you some idea of the size and price range of your backup generator, you will ALWAY want to hire a professional to calculate your electrical load needs. There is no single sizing solution for all homes.

Also, installing your own backup generator is never a good idea. The installation process requires advanced electrical and plumbing expertise, including knowledge of local codes, permits, and inspections. As the National Electrical Code (NEC) gets updated, new requirements may be adopted.

Whole-house backup generators are available in sizes ranging from 5-50 kilowatts (KW). You can use portable generators for small offices, RV’s, and tailgate parties, and industrial sized generators for businesses, data centers, and other larger buildings.

The size and power of the generator is determined by a variety of factors including the size of your home, the type of fuel preferred, and the wattage requirements of your appliances. Don’t forget to take into consideration load growth, seasonal changes, and different types of motors.

Backup Generator Maintenance

Your generator can serve you faithfully for a long time if you run it no more than 75% of its rated capacity, check the oil level after every use, and remember to have it professionally serviced at least every year. You may have to service it more often depending on how often you use your generator, but even if you haven’t needed it the whole year, you should still have it serviced once a year. Call (713) 812-7070 us for your home service and repair needs.

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