The three types of backup power
1. Battery storage
A battery system stores energy and releases it when the grid goes down or when power is expensive. It switches over in milliseconds, so your lights never flicker and your servers never reboot. It makes no noise, needs no fuel delivery, and lives happily in a garage, utility room, or equipment yard.
Its limit is duration. A typical battery carries a building's essential circuits — refrigeration, internet, critical outlets, and often the HVAC — for somewhere between eight and twenty-four hours depending on capacity and discipline. Pair it with solar and that window extends indefinitely in daylight. Without solar, when the battery is empty you are waiting on the grid like everyone else.
2. Portable generator
The cheapest entry point and the most manual. You roll it out, fill it with gasoline, start it, and run extension cords to whatever matters most. It is a legitimate answer for short, infrequent outages if you already own one and know how to use it safely.
The costs are hidden in the operation: fuel you have to source during the exact event that closed the gas stations, refueling every eight to twelve hours around the clock, noise, and carbon monoxide risk that kills people every storm season. It must run outdoors, well away from windows and doors, always.
3. Standby generator
A permanently installed unit wired to your electrical panel through an automatic transfer switch and fed by natural gas or propane. When utility power drops, it starts on its own in roughly ten to thirty seconds and runs as long as fuel keeps arriving — which, on a natural gas line, is effectively indefinite.
This is the answer for multi-day outages and whole-building loads. The trade-offs are upfront cost, permitting, a concrete pad, gas line work, and periodic maintenance. It also does nothing for you on the other 364 days of the year: a generator is insurance, not an asset.
When each one is right
- Outages measured in hours, a handful of times a year. A battery is the better experience — instant, silent, zero maintenance, and it can also shave peak-rate consumption the rest of the year.
- Outages measured in days, or medical and refrigeration-critical loads. A standby generator on natural gas is the reliable answer. Duration beats elegance.
- Tight budget, rare events, and someone home to run it. A portable generator with a properly installed interlock is defensible. Never backfeed a panel through a dryer outlet.
- Both, honestly. Battery for the first few hours and everyday value, generator for the long tail. Many commercial sites run exactly this configuration.
One more variable that decides more cases than people expect: what you are protecting. Protecting a refrigerator and a Wi-Fi router is a different engineering problem than protecting a 5-ton rooftop unit or a walk-in cooler with a hard-start compressor. Size the system to the surge load, not the running load.
The commercial battery hosting program: get paid instead of paying
Everything above assumes you are buying backup power. For commercial buildings there is a third path where the economics run in the other direction.
Grid operators need capacity they can call on during peak events. Rather than building new peaker plants, they pay for distributed capacity sitting inside existing buildings. In a hosting program, a battery system is installed at your property at no upfront equipment cost. You get the backup power. The grid gets the capacity during a handful of called events per year. You receive an annual payment for hosting it.
In practice, qualifying commercial buildings nationwide see annual payments in the $2,000–$10,000 range *With Approval depending on size, load profile, and utility territory, with the specific amount confirmed on approval before anything is installed. Qualification generally comes down to a few things:
- Commercial or multifamily property in a participating utility territory.
- Adequate electrical service and physical space for the equipment.
- Owner authorization, or a landlord willing to sign.
- A load profile the program can actually use during peak events.
The right way to evaluate it is not "battery or generator." It is: does my building qualify for a program that installs a battery for free and pays me annually, and do I still need a generator on top of that for long- duration coverage? For a lot of properties the answer is yes to the first and no to the second.
Eligibility takes about a minute to check and does not obligate you to anything. If the building does not qualify, we will say so plainly and price conventional options instead.