Key takeaways
- A standby generator runs automatically and can power the whole home. A portable generator with an interlock covers essentials for less money and more hands-on effort.
- In San Antonio, air conditioning is the load that drives sizing. A generator that cannot start and run your AC will not keep you comfortable in July.
- Never backfeed a generator through an outlet. It is illegal and can kill a lineman. A transfer switch or interlock isolates you safely.
- Whatever you choose gets sized to your real loads, permitted, and wired to code.
Texans do not need convincing about backup power anymore. A hard freeze, a summer grid strain, a storm that drops a line, and suddenly the house has no power in weather that is not forgiving. For San Antonio homes, backup power is really a question about heat: can it keep the air conditioning running. That single question shapes almost every decision, so let us walk through it honestly.
Standby or portable: which one is right for me?
There are two real paths. A standby generator is permanently installed on a pad outside, wired into your home, and it starts automatically within seconds of an outage using an automatic transfer switch. It runs on natural gas or propane, so there is no refueling, and it can carry the whole house if sized for it. It costs more up front and requires professional installation and a fuel source.
A portable generator is the other path. Paired with a properly installed interlock kit and inlet, it lets you safely power the essential circuits you choose. It costs far less, but it requires you to roll it out, start it, and manage fuel during the outage. It is a strong option for covering the refrigerator, some lights, and a window unit, though a typical portable will struggle to run central air.
Why does air conditioning drive the sizing?
Because in San Antonio, the outage you most fear is in July, and the load you most want is the air conditioner. Central AC is not just a large continuous load, it is a large starting load. The compressor draws a big spike of current at the moment it kicks on, and a generator has to handle that surge without stalling or browning out. Size a generator only for its running watts and ignore that starting surge, and you end up with backup that cannot run the one thing you bought it for.
This is exactly why we run a load calculation before we quote a generator installation. We look at your AC, your well pump if you have one, and the circuits you actually want to keep alive, then size the unit to reality.
Why can I not just plug a generator into an outlet?
This is the most important safety point, so it gets its own section. Running a cord from a generator into a standard outlet, called backfeeding, energizes your entire panel. From there, power can flow back onto the utility lines, where a lineman working to restore power expects them to be dead. Backfeeding can kill that person. It can also destroy your generator and start a fire when utility power returns. It is illegal, and there is never a reason to do it.
The safe alternative is simple. A transfer switch or an interlock kit physically prevents your home from being connected to the generator and the grid at the same time. It isolates you, so your generator powers your house and nothing flows back to the lines. Every generator we hook up gets one of these, no exceptions.
How much does a home generator cost in San Antonio?
The range is wide because the two paths are so different. A portable-ready setup with an interlock and inlet is the more affordable route, mostly the cost of the electrical work plus the generator you buy. A whole-home standby system is a larger investment that includes the unit, the pad, the transfer switch, the electrical, and coordination with a gas fitter for the fuel line. TODO(operator): add your flat-rate ranges for interlock installs and standby installs once set. Either way, we quote the electrical flat and you approve it before we start.
Who handles the gas line?
We wire the electrical and coordinate with a licensed gas fitter for the fuel side, and we keep the trades in sync so the install lands on schedule. You get one accountable point of contact instead of chasing two contractors who blame each other.
We install generators across the metro, and demand runs high in areas with larger lots and well pumps like Boerne and Helotes. Call and we will size the right backup for your home and your budget.