Start with the load, not the unit
Generators are sold by kilowatt rating, but the right size comes from what you need to keep running and how those loads start. A load calculation lists each circuit you want backed up, adds up running demand, and then accounts for starting surges, because motors, compressors and pumps can draw several times their running current for a moment when they start.
- Undersized units trip, stall or run hot, and can shut down under a large starting load.
- Oversized units cost more to buy and install, and lightly loaded engines can wear poorly.
- Load management lets a smaller unit carry a larger building by sequencing or shedding big loads such as air conditioning.
Commercial and residential are different jobs
| Commercial & public facilities | Residential | |
|---|---|---|
| Why backup power | Life safety, refrigeration, data and communications, security, and keeping revenue-producing operations open. | Comfort, refrigeration, medical equipment, sump pumps and keeping the home usable during outages. |
| Code category | Often emergency, legally required or optional standby systems, each with different requirements for transfer, wiring and testing. | Typically optional standby. |
| Transfer equipment | Automatic transfer switches, sometimes multiple, sized to the load and the service, with defined transfer times for critical circuits. | Usually a single automatic transfer switch, often service-entrance rated, at the main panel. |
| Fuel | Natural gas, propane or diesel depending on size, runtime needs and fuel supply reliability. | Natural gas or propane. |
| Approvals | Electrical permit and inspection, plus mechanical, fuel and possibly air-quality or fire-authority review. | Electrical permit and inspection, plus gas or fuel permitting and utility coordination. |
Transfer switches: the part people underestimate
The transfer switch safely moves your building from utility power to the generator and back. It also prevents your generator from feeding power back onto the utility lines, which is a serious hazard to line workers. Choosing the switch means matching its rating to the service or the backed-up panel, deciding between whole-building and selected-circuit backup, and confirming it meets the code category your facility falls under.
Fuel and placement
- Natural gas gives continuous runtime while the gas utility is running, but depends on the pipeline staying up and on adequate pipe size and pressure.
- Propane is stored on site, so runtime depends on tank size, and it needs correct tank placement and regulators.
- Diesel is common for larger commercial systems, with on-site storage, and can trigger emissions and storage requirements.
- Placement is governed by the manufacturer's clearances and local code: distance from doors, windows and air intakes, service access, noise, and flood or wind exposure.
Permits, inspection and testing
A properly installed system is permitted, inspected and commissioned. We coordinate the electrical permit and inspection, work with the fuel and mechanical authorities where they apply, and test the system under load before hand-over. Emergency and standby systems are meant to be exercised and maintained on a schedule, and industry standards set expectations for testing and record keeping in commercial settings.
Backup power in Texas
Extreme heat and severe weather have caused long outages in Texas, and when the grid is stressed, outages can be extended and widespread. For commercial sites, sizing for cooling loads and confirming fuel supply for a longer outage are worth planning up front.
Backup power in Nevada
High ambient temperatures affect generator cooling, derating and enclosure choices, and desert conditions mean dust and heat exposure should be part of the equipment and placement decision.
Backup power in Florida
Hurricanes bring long outages, high winds and flooding. Placement and elevation, wind and flood considerations, corrosion-resistant equipment and fuel supply for extended outages all deserve attention in the design.
Common questions
How long does installation take?
It depends on the size of the system, permitting timelines and fuel connection. A straightforward residential install is far quicker than a commercial system with multiple transfer switches, and we give a schedule with the written quote.
Will a generator run my whole building?
It can, if it's sized for it, but many buildings back up selected critical circuits instead. We help you decide which approach fits your budget and risk.
Do I need a permit?
Almost always. Standby generators involve electrical work and fuel connections that are permitted and inspected. Requirements vary by location, and we handle the process.
Can you service a generator someone else installed?
We can inspect the electrical side of an existing system, including the transfer switch, wiring and protection. Manufacturer-specific engine service and warranty work should go through the manufacturer's own channels.
What about an emergency outage right now?
We provide emergency service around the clock. Use the emergency request form, and if anyone is in danger call first.