Last updated August 31, 2026
A powerful storm swept through San Antonio on Friday evening, August 28, bringing damaging winds, heavy rain, lightning and widespread power outages.
The National Weather Service reported widespread straight-line wind damage from northeast Bexar County through central San Antonio and into southwest Bexar County. Measured winds reached 50 to 65 mph, with pockets estimated at around 75 mph, bringing down trees, power lines and utility poles and damaging some roofs.
San Antonio International Airport recorded 1.69 inches of rain, compared with just 0.11 inches normally recorded on August 28.
The impact on the power system was immediate. CPS Energy reported approximately 112,000 customers without power at the peak, with more than 63,000 still without electricity by Saturday afternoon.
The scale of the physical damage made restoration more complicated. By Sunday morning, CPS Energy had received more than 600 downed-wire orders and 120 tree-trimming jobs. Crews were dealing with damaged poles, transformers and lines, as well as trees and debris that had to be cleared before electrical repairs could safely begin.
By early Monday morning, the situation had improved significantly, but recovery was not over. Around 4,300 customers across 393 outages remained without power, with many of the remaining outages concentrated on the West and Southwest sides. CPS Energy had restored power to more than 85,000 customers on Sunday alone, but warned that some of the more complex repairs could take several days.
For residents still without electricity, the timing is particularly difficult. San Antonio entered the storm after 12 consecutive days at or above 100°F, and temperatures returned to the upper 90s over the weekend. Without power, air conditioning, refrigeration, internet access, medical equipment and the ability to charge essential devices can quickly become more than matters of convenience.
The City opened six overnight resilience hubs, offering residents a cool place to stay, basic supplies, electricity, device charging and Wi-Fi. Eighty-four people, including children, and 18 pets stayed in the hubs Saturday night. VIA also provided free transportation to resilience hubs and daytime cooling locations.
The response illustrates what resilience looks like at a city level: having another way to meet essential needs when normal infrastructure is temporarily unavailable.
The same principle can apply at home.
What can homeowners do during an extended power outage?
Backup power isn't one-size-fits-all. A household that needs to keep a refrigerator, lights, internet and medical equipment running has very different requirements from one trying to power central air conditioning, an electric water heater, pool equipment and other large loads.
The first step is deciding what actually needs to keep running, and for how long. That determines the amount and type of backup power a home needs.
It's also important to know that solar panels alone don't typically keep a home powered during an outage. Most grid-tied solar systems shut down automatically when the grid goes offline to prevent electricity from being sent onto utility lines while crews may be working on them.
For a home to continue using electricity during an outage, the system needs to be designed with backup capability.
Battery backup and solar during an outage
A properly configured home battery can automatically isolate a home, or selected circuits, from the grid and continue supplying stored electricity. The switch to battery backup can happen in a fraction of a second, making the transition effectively seamless. In some cases, homeowners may not even realize the grid has gone down until they notice the rest of the neighborhood is without power.
Depending on the system, that could keep refrigerators, lights, internet, outlets, medical equipment, appliances or even HVAC equipment running.
How long that backup lasts depends on battery capacity and household consumption. Running a refrigerator and a few essential circuits uses far less energy than continuously running central air conditioning, for example.
Pairing batteries with solar can extend that capability during a longer outage. When configured for backup operation, solar can help power the home and recharge batteries during daylight hours, with stored energy available when solar production falls or stops overnight.
For outages lasting several days, a home microgrid can take this a step further. By combining solar generation, battery storage and energy management, a home can produce, store and manage its own electricity while disconnected from the grid. A generator can also be integrated into some microgrid systems, adding another source of backup power when solar production and stored energy aren't enough.
It isn't unlimited power. Weather, solar production, battery capacity and household consumption all affect how long a home can operate. During a prolonged outage, managing which loads are running can make a significant difference.
What about generators?
Standby generators offer another option for extended outages. Unlike a battery with a fixed amount of stored energy, a generator can continue operating as long as its fuel supply remains available, which can make it useful for homes with larger loads or longer backup requirements.
One important difference is how quickly backup power becomes available. Battery systems can switch over in a fraction of a second, while a standby generator needs time to detect the outage, start and begin supplying power. That can mean waiting anywhere from around 30 seconds to several minutes, depending on the system.
There are tradeoffs. Generators require fuel and maintenance and produce noise and exhaust. Batteries operate without onsite combustion and can recharge from solar, but their available energy and power output are limited by the system's capacity.
For homeowners looking for greater resilience during multi-day outages, the answer doesn't necessarily have to be batteries or a generator. A properly designed home microgrid can bring solar, battery storage and generator backup together, using each energy source where it makes the most sense.
The right approach depends on what needs to stay powered and for how long.
What this weekend's storm shows about preparedness
Friday's storm left more than 100,000 customers without electricity at its peak, and thousands were still waiting for power days later.
That doesn't mean every San Antonio household needs a battery or generator. It does show the value of thinking about resilience before an outage happens.
For homeowners, that can mean knowing where community resources are available, identifying which appliances and systems are essential, and understanding what different forms of backup power can realistically provide.
A useful question to start with is:
What does my household need to keep running if the grid is unavailable for a day or longer?
The answer will be different for every home.
Planning for backup power and resilience
At Atma Energy, our engineering team designs solar, battery storage and backup power systems around how a home actually uses electricity and what the homeowner wants to keep running during an outage.
If this weekend's outages have raised questions about your own home's backup options, talk to a Solar Advisor about what you want to keep running during an outage and which backup solutions could make sense for your home.