August and September are the busiest weeks of Gulf Coast hurricane season — and the worst possible time to start shopping for a standby generator. Here is what one actually costs, how to size it honestly, and why the quiet parts of the install matter more than the sticker price.
Everyone on this coast has a version of the same memory: the food in the freezer, the heat with no air conditioning, the phone at 4%, the neighbor’s portable generator running an extension cord through a window. Whether it was Ike, Harvey, Beryl, or a February freeze, the lesson landed the same way — power here is not guaranteed, and the outages that matter are measured in days, not hours.
A permanently installed standby generator is the answer to that, but it is a real investment and the quotes vary wildly. Let us make the numbers make sense.
What a Whole-House Generator Actually Costs
The number people quote each other at the hardware store is the equipment price. The number that matters is the installed price, because roughly a third to a half of a generator project is everything other than the generator itself.
| System size | What it typically runs | Typical installed range |
|---|---|---|
| 10–14 kW | Essential circuits: refrigerator, well or sump, some lighting, outlets, one AC system in many homes | $6,000 – $10,000 |
| 18–22 kW | Most of a 2,000–3,000 sq ft home, including central AC and electric appliances | $9,000 – $15,000 |
| 24–30 kW+ | Larger homes, two AC systems, shops, well pumps, EV charging | $14,000 – $22,000+ |
Treat those as planning ranges, not quotes. Real pricing swings on how far the unit sits from your electrical panel and gas meter, whether your panel needs upgrading, local permitting, and whether you need a full-service or essential-circuits transfer switch. Every honest estimate for this work comes after somebody looks at your panel, your gas supply, and your yard.
Where the money actually goes
- The generator itself — usually 50% to 65% of the total.
- The automatic transfer switch — the device that safely disconnects you from the utility and starts the generator. Non-negotiable, and the single most important safety component in the system.
- Gas supply — running and sizing a natural gas line, or setting a propane tank. Undersized gas piping is one of the most common problems we find on generators installed by somebody else.
- The pad and set — concrete or composite pad, elevated appropriately. On this coast, elevation above expected flood levels is not optional.
- Electrical work — conduit, conductors, bonding, and often a panel upgrade if your service is older or already full.
- Permits and inspection — required, and worth having in writing when you file an insurance claim later.
Never back-feed a portable generator into a wall outlet. That “suicide cord” trick sends power backward onto the utility lines, which can kill the lineman working to restore your neighborhood, and it puts your own family at risk. If you use a portable, it needs a proper interlock kit or transfer switch installed by an electrician.
How to Size a Generator Without Overbuying
Sizing is where most quotes diverge, and where a lot of money gets wasted. There are two legitimate approaches.
Whole-house coverage
The generator carries essentially everything, and life during an outage looks normal. Simple, comfortable, and the most expensive path. For most Gulf Coast homes with central air, this starts around 22 kW and climbs from there with square footage and a second AC system.
Managed or essential-circuit coverage
A smaller generator carries a selected list of circuits, and smart load management sheds lower-priority loads automatically when demand spikes. In practice this means your AC, refrigerator, lights, internet, and outlets stay up, while the electric dryer and oven wait. It commonly lets homeowners drop one full size class — often several thousand dollars — without a meaningful comfort difference during a storm.
The number that drives everything: your air conditioner
In our climate, AC is the load that decides the generator size. A compressor’s starting surge is several times its running draw, and that inrush is what a generator has to swallow without stumbling. This is exactly why generator sizing should be done by somebody who understands both the electrical panel and the HVAC equipment — sizing off square footage alone is how homes end up with a generator that trips every time the AC cycles on.
Natural Gas or Propane?
Natural gas is the easier choice where the utility line is available: unlimited runtime, nothing to refill, no tank in the yard. The catch is that gas service can be interrupted in a severe event, and your existing line may need upsizing to feed the generator alongside your other appliances.
Propane is independent of the gas utility and stores well, which matters in a hurricane scenario. It costs more per hour of runtime, and you are responsible for keeping the tank filled — a 500-gallon tank is a realistic starting point for multi-day outages.
Get a Real Generator Number for Your Home
We size, install, permit, and service standby generators across Galveston and Brazoria counties — and we look at your panel, your gas line, and your AC load before quoting a thing.
Five Questions to Ask Any Generator Installer
- Is a permit being pulled, and who schedules the inspection? If the answer is vague, keep shopping.
- Did you calculate my AC starting load, or estimate from square footage? Only one of those produces a generator that works.
- Is the gas line being resized for the added demand? A generator sharing an undersized line with a furnace and water heater will starve.
- How high is the pad, relative to past flooding on this street? A flooded generator is a total loss and rarely covered the way owners expect.
- What does the maintenance schedule look like, and do you service what you install? Standby units need oil changes, filters, battery checks, and an annual load test — the battery is the number one reason a generator fails to start when the storm arrives.
Do Not Skip the Maintenance
A standby generator sits idle for months, exercises itself weekly, and then is asked to run continuously for days. The failures we get called out for during outages are almost never dramatic: it is a dead starting battery, old oil, a clogged air filter, or a unit that has not been load-tested since the day it was installed. An annual service visit before June is the cheapest insurance in this entire article.
Frequently Asked Questions
What size generator do I need for my house?
For most Gulf Coast homes with central air, 18–22 kW covers whole-house needs, and 10–14 kW with load management covers the essentials comfortably. The deciding factor is your AC’s starting draw and your panel’s configuration, so a load calculation beats any rule of thumb.
How long can a standby generator run continuously?
On natural gas, effectively as long as the gas keeps flowing — days on end — with scheduled oil service on extended runs. On propane, runtime is a function of tank size and load; a 500-gallon tank commonly supports several days of typical use.
Will a whole-house generator run my air conditioner?
Yes, when it is sized for the compressor’s starting surge, not just its running watts. Soft starters can also reduce that inrush and sometimes allow a smaller generator.
Does a generator add value to my home?
On this coast buyers understand exactly what it is worth. It is also worth asking your insurer about it — some carriers offer credits, and a generator that prevents freeze damage or spoiled food pays for itself in avoided claims.
How long does installation take?
The physical install is typically one to three days once equipment and permits are in hand. The lead time before that is the variable, and it stretches considerably once a named storm enters the Gulf. Late winter and spring are the calm windows.
Learn more about our generator installation and electrical services, ask about financing options, or reach the team through our contact page. Serving Santa Fe, League City, Manvel, Alvin, Dickinson, and Texas City.