Practical guide: What size generator should you choose for your business?

In today's business world, experiencing a service interruption is no longer an option. Whether brief or prolonged, a power outage can quickly threaten your operations and revenue. The real question, therefore, is no longer whether your business needs a backup generator, but rather what size generator will ensure business continuity.

Underestimating your needs will leave you in the dark, while oversizing will unnecessarily increase your bill. To avoid these pitfalls, Protech Generators has created this practical guide to help you target the perfect power output.

Workload assessment: the basis of your decision

Before exploring the different models of commercial generators, you need to identify the equipment that must remain operational at all times. Depending on the type of business, this can go far beyond simple lighting.

Here are some examples of items that could be part of your essentials:

• Security and alarm systems
• Cash registers and payment systems
• Emergency lighting and minimal lighting
• Specialized equipment depending on your sector (freezers, computer servers, etc.)
• Basic heating or ventilation system

Once the list of devices and systems to be kept active simultaneously has been established, you will need to determine, for each of them, two types of power:

1. Operating power (or rated power): The power required to operate the device.
2. Starting power (or peak power): The additional and temporary power required by some devices to start.

Power calculation: leave nothing to chance

Once you have listed your equipment, along with its individual power rating in watts (running and starting), the calculation is simple, but requires precision. The goal is to ensure that the generator can handle the required continuous operating load, in addition to the highest starting peak.

Step 1: Total the operating power

Add together the rated power of all the equipment you want to run simultaneously during a power outage.

For example, if minimum lighting (500W), security system (150W) and commercial refrigerator (1500W) are required, your total rated power is 2150 Watts.

Step 2: Identify the maximum startup peak

Look at the list of selected equipment and then identify the device with the highest peak power (often a motor or compressor). This energy surplus, although short-lived, must absolutely be factored into your calculations to determine the size of your future generator.

To do this, you add the total rated power and the difference between the peak power and the operating power of the most powerful motor.

In our example, the refrigerator requires 5000 W at startup and 1500 W continuously. The calculation is therefore: 2150 W + (5000 W - 1500 W) = 5650 Watts.

Your generator must therefore be able to supply a minimum of 5650 Watts to handle the highest starting peak.

Choose a generator of the appropriate size

For performance, safety, and longevity reasons, your commercial generator should never be run at full capacity. We strongly recommend adding a safety margin of approximately 20%, limiting its use to 80% of its power output. This is a good practice to anticipate potential additional needs or unforeseen events while avoiding possible power surges.

Continuing with our example, the actual power requirement is 5650 Watts + a 20% safety margin, we get 6780 Watts.

In this case, a 7000 Watt generator would be more than sufficient.

Choosing the type of generator: fixed or portable?

For a business, the solution rarely lies in portability. Every minute lost searching for, starting, and manually connecting a generator is time and manpower lost for your operations.

The true guarantee of uninterrupted productivity is the automatic (fixed) generator. It takes over instantly upon detection of a failure, without any human intervention. A wise investment for complete peace of mind.

The advantages of a stationary generator are significant:

Protech Generators' Expertise at Your Service

While this guide has helped you understand the basic principles of power calculation, some important technical details remain. To ensure the efficiency and reliability of your backup power system, we strongly recommend having your estimate validated by certified technicians.

The experts at Protech Generators specialize in assessing commercial loads and installing Kohler generators of all sizes. Our comprehensive services ensure a turnkey solution: from a precise evaluation of your needs to complete installation, including connection to the power supply.

Don't let breakdowns threaten your operations any longer. Contact us today for an accurate assessment of the ideal generator size for your business and ensure the continuity of your operations under all circumstances.

Request your free estimate