Commercial Generator Replacement

Emergency generators are critical to the safe operation of commercial buildings during power outages and emergencies. Emergency generators typically provide backup power to emergency lighting, elevators, fire alarms, fire pumps, sump pumps, domestic water pumps, and other critical equipment and branch circuits. End of life commercial generator replacement of these systems requires several steps and encompasses many trades.

If it's time for a commercial generator replacement, contact the experts at Assurance Power Systems at 561-866-0470 or use our online form to request a quote. We have been serving business owners in South Florida since 2005 and can help you find the best generator to keep your business running without interruptions.

End of Life Considerations

When an emergency generator reaches end of life, it may be tempting to just replace it with a system of equal size and configuration. While this may be feasible, it is important to note that upgrades and or system design changes may be required to comply with current codes. Additionally, it is important to determine what loads are protected by the emergency generator and decide if any additional loads are desired to provide a safer or more functional building during emergencies and power outages.

It is important to consult with an experienced contractor or design professional that specializes in emergency power supply systems. Several codes govern the installation, maintenance, and replacement of emergency power supply systems including NFPA 110, NFPA 37, NFPA 20, NFPA 70, NFPA 54, NFPA 58, NFPA 90A and 90B, NFPA 99, NFPA 101, plus any local codes and zoning requirements.

Many commercial buildings are legally required to own and maintain an emergency power supply system. When these systems are inoperable due to component failure, the building owners must provide for a backup system. This is an important budget consideration because many building owners wait until catastrophic failure to replace their system. Given that replacement projects can take anywhere from 4 months to a year depending on scope, permit approvals, and lead time, the added expense of a backup system can significantly drive up the total cost of ownership. The best practice is to follow a more proactive approach by identifying an end of life date and sticking with it. As a bonus, an older but functional emergency generator system has more salvage value than an inoperable system that’s worth nothing more than scrap metal.

Of course, unexpected and premature component failure can happen causing building owners and property managers to have to rush through the commercial generator replacement process. Contingency funds should always be set aside to account for the cost of renting a backup generator. The surest way to prevent this is to ensure your maintenance program follows the NFPA 110 guidelines. Hiring a professional company to maintain an emergency generator system in accordance with the NFPA 110 can significantly decrease the total cost of ownership by extending its useful life.

Scope of Commercial Generator Replacement Projects

Replacing an commercial generator system is a complex process that encompasses multiple trades:

• Electrical – Feeders and control wires; transfer switch installation

• Structural – Concrete slabs and walls

• Fuel Systems – Natural Gas, Liquid Propane, Diesel

• Mechanical – Exhaust piping, shrouds, ventilation

• Rigging & Crane

• Generator specific control systems


In addition, MEP and Structural engineers are usually required to design the replacement system and ensure code compliance. If you don’t work with a contractor licensed in all these trades, be prepared to coordinate multiple vendors or pay a general contractor to coordinate the various trades.

The proper sequencing of the project is critical to ensure a smooth commercial generator replacement. The project should start with a comprehensive design package provided by a MEP Engineer in coordination with an experienced contractor. Once this drawings set is complete, permit approvals should be obtained to ensure the building department approves the system. Once the project is approved by the authority having jurisdiction, the equipment should be ordered. It is important to note that ordering the replacement commercial generator equipment prior to the necessary approvals creates unnecessary risk because emergency generators are manufactured specifically for each project – any changes needed can be costly or, worse, render the ordered system noncompliant with the changes specifications.

If the existing emergency generator system is inoperable, demolition work can start once the necessary permits are approved or with special permission from the building official (this assumes a backup generator has been mobilized and is properly connected to the transfer switch or switches). If the existing system is still operable, taking if offline prematurely can add cost by requiring a portable generator longer than necessary.

Commercial generator replacement can require power shutdowns to install and test the system. Properly planning this work is essential to minimizing the impacts to your building and occupants. Additionally, shutdowns may need to be coordinated with the utility company (fees may be associated). A portable backup generator can be utilized to minimize the downtime during any work needing power shutdown.

Generator System Design Considerations

Several factors should be considered during the design process: location, loads supplied, and fuel source to name a few. Location can affect the lifespan of the system – interior systems tend to have longer lifespans than their exterior counterparts. It can also affect the safety and enjoyment of the occupants. Poorly designed systems can create unnecessary noise, smells, and fumes in occupied areas.

The loads supplied by the commercial generator should be evaluated to determine if more (or less) is needed or desired. Greater loads can increase this size of the generator and, consequently, its footprint. Additionally, larger generators need more airflow and ventilation, larger exhaust piping, and have greater fuel requirements.

Lastly, fuel source is an important consideration as technology and codes have changed. Advancements in spark ignited engines have leveled the playing field dominated by diesel systems. Natural gas is becoming more widely acceptable as a reliable fuel source and being made more readily available. Propane and natural gas fuel systems are cleaner and less expensive to maintain. However, these systems are only cost competitive at 150kW and below (as of the time of this writing). Gaseous engines above this threshold are costlier than their diesel counterparts. It is important to note that natural gas and propane fuel systems require very little maintenance and can offset the higher cost of annual diesel fuel polishing.

In summary, commercial generator replacement requires careful planning, proper budgeting, and partnering with a qualified team of professional engineers and contractors. Neglecting any of these can have significant impacts on cost, liability, and occupant satisfaction.

Contact Assurance Power Systems for Commercial Generator Replacement

Assurance Power Systems is a Florida based General, Electrical, Mechanical, Natural Gas & Liquid Propane, Plumbing, and Pollutant Storage contractor specializing in the sale, installation, service and replacement of standby and emergency generator systems. They have been recognized by Generac Power Systems as the best dealer in the U.S. They are industrial dealers for Generac and Kohler, providing full sales and service capabilities. Additionally, they are called upon by Cummins on new installation and replacement projects. Assurance Power Systems is a truly unique generator company.

To learn more about commercial generator replacement, or to request a free quote, give us a call at 561-866-0470 to speak to one of our friendly representatives.

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