Quick Answer
Commercial backup power is a standby generator and transfer system that keeps a business running when the grid goes down — including during a Public Safety Power Shutoff. For North Bay businesses, it protects revenue, refrigeration, data, and safety systems through outages that can last days. A licensed electrician calculates the loads that must stay on, sizes the system to them, and installs a transfer switch that moves the building from grid to generator. It’s planned around what your operation genuinely can’t afford to lose.
Key Takeaways
- A Public Safety Power Shutoff (PSPS) is a planned utility outage during high fire-risk weather that can leave North Bay businesses without power for hours to days.
- Commercial standby power protects the loads a business can’t afford to lose — refrigeration, POS and data, security, lighting, and critical equipment.
- Systems can back up an entire building or just essential circuits, and the right scope comes from a load assessment, not a catalog.
- An automatic transfer switch moves the building from grid to generator so the transition is fast and controlled.
- Commercial installs are permitted, code-driven, and tested under load — and a good electrician scopes them to what your operation actually needs.
Commercial backup power is a standby generator paired with a transfer system that keeps a business operating when utility power fails. When the grid drops — whether from a storm or a planned Public Safety Power Shutoff — the system detects the loss and supplies the building’s essential circuits until the grid returns. For a North Bay business, that’s the difference between closing for the duration of an outage and staying open. It’s infrastructure that only matters on the days it matters entirely, which is exactly why it’s planned deliberately rather than improvised.
What is commercial backup power and what does it do?
A commercial standby system works by continuously monitoring utility power and starting the generator automatically when it’s lost, with a transfer switch redirecting the building’s load from grid to generator. The scope is defined by which loads have to stay energized. According to the California Public Utilities Commission, PSPS events are used by utilities during dangerous fire weather to reduce ignition risk, and they can affect wide areas for extended periods — which is why businesses in fire-prone corridors treat backup power as continuity planning, not a luxury.
A Public Safety Power Shutoff (PSPS) is a planned, precautionary power outage a utility initiates during extreme fire-weather conditions to reduce the risk that its equipment sparks a wildfire.
Why the North Bay makes this a business decision
Marin and Sonoma sit squarely in PSPS territory, and the businesses that feel it most are the ones with perishable inventory, customer-facing hours, or systems that can’t simply go dark. A Petaluma restaurant, a Novato medical office, a Sonoma retailer with refrigerated stock — each has a different set of must-stay-on loads. PG&E’s own PSPS guidance encourages customers in high fire-risk areas to prepare for extended outages, and for a business that preparation is a backup plan. When we scope commercial backup, we start from that operational reality. If you’re a homeowner reading this for a residence, our whole-home vs. portable generator guide is the better starting point.
A standby generator is a permanently installed generator that starts automatically when utility power is lost and supplies a building’s essential or whole-building load until power returns.
What does backup power actually protect in a business?
Backup power protects the loads a business genuinely can’t afford to lose during an outage: refrigeration, point-of-sale and data systems, security and access control, essential lighting, and critical equipment specific to the operation. For a food business, that’s inventory that spoils; for a medical or dental office, it’s records, refrigerated supplies, and the ability to see patients; for a retailer, it’s the ability to transact at all. The value of backup power isn’t abstract — it’s the revenue and inventory that keep flowing while competitors sit dark.
Why the load list is the whole conversation
The single most important step is deciding what has to stay on. A business rarely needs to back up every circuit; it needs to back up the ones tied to revenue, safety, and loss prevention. That list — refrigeration, servers, POS, security, emergency lighting, maybe a specific piece of equipment — drives the size of the generator and the design of the transfer system. Getting it right means the system is neither undersized in a crisis nor oversized on the invoice, which is why a real load assessment comes before any equipment is named.
Backup power isn't about running everything. It's about knowing precisely what your business can't afford to lose — and guaranteeing that stays on.— Towery Electric
What are the options for commercial backup power?
The main options for commercial backup power are a whole-building standby system that carries the entire load, an essential-loads system that backs up only critical circuits, and — for lighter needs — portable generators with a manual connection. Whole-building systems offer seamless, complete coverage at higher cost; essential-loads systems focus the investment where it counts; portable setups are the most limited and least automatic. The right choice depends on the operation, and the table below frames the trade-offs.
Which option fits is a function of what’s on your must-stay-on list and how much downtime your business can tolerate. A restaurant with walk-in refrigeration and a full dinner service has a very different answer than a small office. The transfer method matters too — an automatic switch restores power in seconds, while a manual one depends on someone being on-site. If you also run commercial equipment on a tight electrical service, our guide to commercial panel upgrades covers the capacity side of the picture.
| Option | Typically fits | Key trade-off |
|---|---|---|
| Whole-building standby | Businesses needing full, seamless coverage | Highest cost; carries the entire load automatically |
| Essential-loads standby | Most businesses protecting critical circuits | Focuses investment on must-stay-on loads |
| Portable + manual connection | Very small operations with limited needs | Manual, limited capacity, requires on-site staff |
How does a commercial backup installation work?
A commercial backup installation works as a planned, permitted project: assess the critical loads, size the generator and transfer switch, install and integrate the system, then test it under load. It’s an engineered process because a business depends on it performing on the worst day, not a typical one, and the installation follows the National Electrical Code for generator and transfer-switch wiring. Coordination with the utility and local jurisdiction is part of the job. If your building’s electrical service needs headroom first, that’s identified early rather than discovered mid-install.
- Load assessment. We work with you to define which circuits must stay energized and calculate the real electrical demand behind them.
- System sizing & design. The generator and transfer switch are sized to those loads, with fuel and placement planned for the site.
- Installation & integration. The system is installed, tied into the building’s distribution, and permitted with the local jurisdiction.
- Testing under load. The system is commissioned and tested under real load so you know it will start and carry the business when it counts.
When it’s finished, you have a system that’s been proven — not just installed — and documented for inspection and insurance. What you should expect from a good commercial electrician is a load-driven design, a clear explanation of what’s covered and what isn’t, and a test that demonstrates the system works before you ever need it in an outage.
Wondering what it would take to keep your doors open through the next shutoff? Let's scope it.
Request Your EstimateWhich Marin businesses need backup power most?
The businesses that need backup power most are those with perishable inventory, customer-facing hours, critical data, or safety systems that can’t go dark — restaurants, grocers, medical and dental offices, and any operation where an outage means lost revenue or lost stock. If a multi-day PSPS would force you to close, discard inventory, or fail customers, backup power is continuity insurance. Businesses with flexible hours and no perishable or critical loads have a weaker case, and an honest assessment will say so.
Reading your own exposure
The clearest way to judge your need is to ask what a three-day outage during fire season would actually cost you. If the answer includes spoiled inventory, closed doors during peak hours, at-risk data, or a safety or compliance problem, the case for backup power is strong. If it’s mostly inconvenience, a lighter setup or none may be reasonable. Because PSPS events cluster in the dry, windy months, the businesses in the North Bay’s higher-risk corridors tend to feel the exposure most acutely.
What are the common mistakes with commercial backup power?
The most common mistakes with commercial backup power are guessing at the load instead of calculating it, skipping the permit and load test, and treating fuel and placement as afterthoughts. An undersized system fails at the moment it’s needed; an untested one is a gamble. The California Public Utilities Commission’s PSPS guidance makes clear these events can run for extended periods, so a system sized for a brief blip can leave a business exposed. Cutting corners on a system you’re buying specifically for the worst day defeats the purpose.
How to avoid them
Avoid these by hiring a licensed contractor who runs a real load assessment, sizes for the duration a PSPS can actually last, pulls the permit, and tests the system under load before signing off. Plan fuel supply and generator placement for the site, not as an afterthought. And make sure your electrical service has the capacity to support the design — our guide to standby vs. portable systems covers the fundamentals that apply on the smaller end of the scale, too.
Key Terms
- Standby generator
- A permanently installed generator that starts automatically on power loss and supplies a building's essential or whole load.
- Automatic transfer switch (ATS)
- A device that detects a utility outage and switches a building's load from grid to generator automatically, in seconds.
- Public Safety Power Shutoff (PSPS)
- A precautionary utility power outage during extreme fire weather, which can affect wide areas for extended periods.
- Essential loads
- The specific circuits a business must keep energized — such as refrigeration, POS, data, and security — that drive system sizing.
About the Author
Founder of Healthcare Marketing Group and author of The Ultimate Guide to Digital Marketing. Previously led a digital marketing company with 8,000+ clients. Writes on local-service SEO and E-E-A-T content strategy.
Reviewed By
Alex founded Towery Electric in Novato in 2014 and has installed commercial backup systems for North Bay businesses through multiple PSPS seasons. Reviewed this article for technical accuracy on Aug 18, 2026, 2026.
“For a business, the whole game is the load list. Get that right and the system does its job every time. Guess at it, and you find out what you missed on the worst possible day.”
— Alex Towery, Licensed Electrical Contractor
How We Ensure Accuracy
Sources
- California Public Utilities Commission. “Public Safety Power Shutoffs (PSPS).” cpuc.ca.gov
- PG&E. “Public Safety Power Shutoff.” pge.com
- National Fire Protection Association. “NFPA 70 — National Electrical Code.” nfpa.org
- California Contractors State License Board. “License Detail — Towery Electric, Inc. (#989290).” cslb.ca.gov
- U.S. Department of Energy. “Backup Power and Standby Generators.” energy.gov
Frequently Asked Questions
What is a PSPS and how long can it last?
A Public Safety Power Shutoff is a planned utility outage during extreme fire-weather conditions, used to reduce the risk that power lines spark a wildfire. According to the California Public Utilities Commission, these events can affect wide areas and last from hours to several days depending on conditions. For North Bay businesses in fire-prone corridors, that duration is exactly why backup power is treated as continuity planning rather than an optional extra.
Does my whole business need to be backed up?
Usually not. Most businesses back up only the loads they can’t afford to lose — refrigeration, point-of-sale and data, security, essential lighting, and critical equipment — rather than every circuit. That focused list drives the generator size and keeps the investment proportional. A whole-building system is an option when seamless, complete coverage is worth the cost, but a load assessment is what determines the right scope for your operation.
How is a commercial generator sized?
A commercial generator is sized from a load assessment: an electrician identifies which circuits must stay energized, calculates their real electrical demand, and specifies a generator and transfer switch to match, with margin for how loads actually start and run. Sizing from a catalog or a guess risks a system that fails under real conditions. Because a business depends on it during the worst outages, the sizing is engineered to the operation, not estimated.
What does an automatic transfer switch do?
An automatic transfer switch continuously monitors utility power and, when it detects an outage, switches the building’s load from the grid to the generator automatically — usually within seconds. When utility power returns, it switches back and signals the generator to shut down. For a business, that automation means critical systems barely notice the outage, and no one has to be on-site to manually connect a generator during a PSPS.
Which businesses benefit most from backup power?
Businesses with perishable inventory, customer-facing hours, critical data, or safety systems benefit most — restaurants, grocers, medical and dental offices, and retailers with refrigerated stock. For these operations, a multi-day PSPS can mean spoiled inventory, closed doors during peak hours, or compliance problems. If a three-day outage during fire season would cost you real revenue or stock, backup power is continuity insurance worth scoping with a licensed electrician.
Editor’s Summary
For a North Bay business, a multi-day PSPS can mean spoiled inventory, closed doors, and lost revenue. Commercial backup power keeps the loads you can’t afford to lose energized through the outage. The whole design turns on one question — what has to stay on — which drives sizing, the transfer switch, and cost. A load-driven, permitted, load-tested system is continuity insurance for the days it matters most.