Small Business Brief

Safety & Loss Prevention

Got Backup? How to Choose the Right Commercial Generator for Your Small Business

A commercial generator can be a lifesaver for a small business. Learn more about how to choose the best generator for your business with this handy guide.

Did you know that half of all businesses who experience a major disaster never recover from it? These odds are unnecessarily high when investing in a commercial generator can give you much better odds. If your business isn’t prepared for the worst, then you’re setting your business up for a disaster.

So we’ve convinced you, you need a generator, but where to start? It’s one thing to go to the local hardware store and buy a small one for your home. It’s a much bigger challenge to buy an industrial generator to run a business.

We have put together the ultimate guide to help you get started.

Start with Your Needs

The first thing you need to do is look at what your needs are. One of the most common mistakes people make is under sizing their generator.

Don’t fall into the trap of thinking that because you are buying a backup generator, it doesn’t need to be as big. You can damage both your generator and your equipment by choosing an industrial generator which is too small.

What Is the Right Size?

When sizing industrial generators there is no substitute of consulting a professional. They will perform an inspection and evaluate your energy needs.

You can help by creating a list of your equipment which need powering. Then take note of each one’s starting and operational wattage. Then calculate your running power needs in either KW or KVA.

How to Find the Starting and Running Wattage

The majority of equipment manufacturers will affix a metal plate to the equipment with this information. If it isn’t on the unit, check the owner’s manual.

You might find the amperage need instead of the wattage need. This is still useful as you can convert the amps into watts. There are plenty of handy charts out there, but you can also use this formula.

If you want to factor the resistive load:

Amps x Volts = Watts

If you want to factor the reactive load:

(Amps x Volts) x Load Factor= Watts

What If You Can’t Find Anything?

Sometimes you can’t find the metal plate and you’ve long since lost the owner’s manual. You can look at a power consumption chart to estimate your equipment’s power usage.

You can calculate your consumption needs a couple of different ways. The one you choose depends on how much equipment you have and the way you intend to use the generator.

  1. Single motor
  2. More than one motor running at the same time
  3. No electric motors running

Benefits of Getting the Generator Size Right

When you choose the right sized generator you don’t have to worry about unexpected system failures. This also means no more safety shutdowns by the generator to protect it from overloading.

When you don’t put this kind of extra stress on your generator then the useful life will be longer. An increased longevity means you will save money in repairs and replacements in the long run.

Your maintenance and repair costs will also reduce for both the generator and your equipment.

Automatic or Portable

There are two types of generators on the market. An automatic or standby generator connects directly into your system.

When the power supply cuts, the standby generator will automatically kick on. This will immediately restore the power to your business.

Portable or backup generators have to be manually hooked up and started up. These are not a wise choice for industrial and business applications.

Safety Considerations

Most experts recommend you place your standby generator at least 10 feet from your building. This will reduce the risk of any harmful gasses from entering the building.

You may also want to install carbon monoxide and smoke detectors. These will alert you in the event that any harmful gasses do enter the building.


There is no getting around it – generators are loud. Some models are louder than others, though. Consider this when selecting a model and where you intend to place it.

Automatic generators do tend to be quieter than their portable counterparts. You can also counter the noise factor by making sure it only runs when necessary.  

Fuel Type

The engine in your generator can run on a variety of different fuels. You’ll want to consider them all as they each have their own pros and cons.


You’ll find that this is the most popular type of fuel for generators. The fuel is available and relatively affordable.


This is the most affordable and easiest fuel to get your hands on. The problem is, everyone uses it, for almost everything.

So in an emergency when you need it the most, you may not be able to get more. This could leave you with a problem when the generator runs out of fuel. What’s the point of having a generator to run your business if you can’t run the generator?

You also can’t store it for long periods of time. You need to use it within a year of buying it. Plus, it’s also highly flammable.

Natural Gas

This is a way to go if your company already has a natural gas line. With this method, you don’t have to bother with a storage tank for the fuel.

You also don’t have to worry about the fuel when the temperatures dip low in winter. These generators are on the higher end of consumption. However, natural gas tends to be an affordable fuel source.


Unlike gasoline, propane doesn’t have a shelf life. It is also considered clean burning. But, these benefits come at a higher cost.

The cost of buying and storing the fuel tends to be a big barrier for most businesses. You’ll have to have a storage tank as propane generators use more fuel to run.

Dual Fuel

If your business uses a generator on a daily basis as the main power source then you may want to consider a dual fuel option. This will give you a backup fuel source in case you run out of the first supply.

Three Phase or Single Phase

There are two different ways commercially sized generators supply the power they create. They will either be a single or three-phase process.

A single phase system supplies power in one wave. It will go from 0 to peak power and then back to zero.

Don’t get thrown off by this – the power coming into your home works like that. The peaks and dips happen so fast that you don’t detect them.

This single phase system works fine for smaller businesses. Industrial applications will work better with a three-phase system.

With a three-phase system, there are three waves of power instead of one. Each wave of power has the peaks and valleys. Each wave, though, is slightly out of sync of the others.

This way there is always one wave at the peak to create a consistent line of peak power. The advantage of this is a three-phase generator can create a much higher voltage.

You’ll know which system is better suited for your needs because you followed our first step. Taking the time to calculate your energy needs will help you know which type of generator to buy.

Proper Operation

You need to make sure your future industrial generator complies with all laws and codes. You should consult with an electrician about the local building codes. You also need to confirm that your automatic generator can get wired into the existing system without causing a risk of fire.

Your Budget

All these factors are important, but you also need to consider your budget. You want to invest in your generator, but you don’t need to buy the biggest and most expensive option out there.

You may be tempted by the low cost of the portable generators. But, this savings may cost you more in an emergency.

Choose Your Commercial Generator

Whether it’s protecting against electrical problems or a natural weather event your business needs a generator to keep things running smooth. One of the most important things to consider is the size of the generator you need.

Once you know the size of the generator you need, then you can use this information and your budget to narrow down your choice. You’ll want to decide on placement, hookup, safety standards, and fuel type. While you don’t need to buy the most expensive model, you definitely need to buy a quality commercial generator.

Now you need to know these 7 tips for maintaining your generator.