What Size Generator Do I Need?
We size Generac standby generators from your panel and your loads on a free visit.
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Find the Right Size Generator for Your Home
Power you can count on. Precision you can trust.
Not All Generators Are Created Equal — and Neither Are Homes.
When the power goes out, the last thing you want to discover is that your generator can’t keep up.
Choosing the right size generator isn’t just about keeping the lights on — it’s about making sure your family stays safe, your food stays fresh, and your home stays functional. Whether you want to back up the basics or power your entire property, correctly sizing your generator is essential.
Our Experts Handle the Heavy Lifting
At Wired, we don’t expect you to crunch numbers or figure out wattage on your own.
Our team of licensed professionals will visit your home, evaluate your power needs, and recommend the perfect generator to match your lifestyle. From there, we’ll handle everything — installation, permits, and future maintenance — so you can rest easy knowing you're prepared for anything.
Peace of Mind Starts With the Right Fit.
A properly sized generator isn’t a luxury — it’s a smart investment in reliability.
Whether you’re facing summer storms, rolling blackouts, or unexpected outages, our goal is to make sure your backup power kicks in when you need it most. With fast turnaround times, trusted Generac systems, and a 10-year warranty, we make it easy to protect your home before the next storm hits.
What Will Your Generator Power?
Here’s what most homeowners ask us to protect during an outage:
- Refrigerator & Freezer
- A/C & Heating System
- Lights & Outlets
- Microwave / Small Kitchen Appliances
- Internet & WiFi
- Medical Equipment
- Garage Door Openers
- Security Systems
- Well Pump or Sump Pump (if applicable)
Schedule Your Free Generator Sizing Estimate Today
Don’t Wait Until the Power Goes Out
$2,000 off a generator install. While supplies last.
It only comes off the units on our floor, so when they're gone, it's gone. New air-cooled Generac installs come with a free 10-year warranty, and financing is there if you want it. Permit timing depends on your city or county. The install itself is usually one day.
What Size Generator Do I Need for My House?
The right size depends on what you want running at the same time. Square footage gives a rough idea, but the appliances in your home decide the answer.
Essentials, managed whole house or full whole house
Most homeowners land in one of three groups. Some want only the essentials, such as the fridge, lights, internet and a few outlets. Some want the whole house with load management, where big appliances take turns. Others want everything running at once, including every AC unit. Each choice leads to a different generator size, and we help you pick the one that matches how you want to live during an outage.
Why square footage is not enough
You will see charts that match a generator to a house size, such as a whole house generator for a 2000 sq ft or 3000 sq ft house. They can be a starting point, but they miss what matters. A smaller home with two AC systems, an electric range and a pool pump can need more generator than a larger home with gas appliances. We size from your actual loads.
The Houston factor: air conditioning
In Houston, the AC is usually the biggest load in the house and the one people care about most during a summer outage. An AC compressor pulls a burst of extra power when it starts, well above what it draws while running. A generator has to handle that start without the lights dipping or the unit shutting down. That is the single biggest reason sizing needs a real look at your equipment.
How to Size a Whole House Generator: Running Watts and Starting Watts
Generator sizing comes down to two numbers for every appliance. Understanding them makes the recommendation easier to follow.
Running watts
Running watts are what an appliance uses while it is on and working. Lights, a TV, a router and a fridge that is already cooling all draw running watts. Add up everything you want on at the same time and you get the steady load the generator has to carry. This is the part most online generator sizing calculators handle well.
Starting watts and motor loads
Appliances with motors, such as AC compressors, well pumps, sump pumps and some fridges, need a short burst of extra power to start. That starting load can be well above the running load for a moment. If two big motors start together, the generator has to cover both. A good sizing plan accounts for the largest starts, not just the steady total.
What a generator sizing calculator misses
An online whole house generator calculator is a fine way to get a rough idea, but it depends on what you enter. It cannot see your panel, your AC equipment labels, your service size or how your house actually uses power. It also cannot tell you whether load management would let a smaller unit do the job. That is what the free sizing visit is for.
Load Management: Running More of the House With the Right Generator
You do not always need a bigger generator to run more of the house. Sometimes you need a smarter connection.
What load shedding does
Load management, also called load shedding, lets the generator control when large appliances can run. If the house is near the generator's limit, a second AC unit, a dryer or a water heater waits until there is room. The generator stays within its capacity, and you keep the things that matter running. When a large load finishes, the next one gets its turn, so the house keeps working without overloading the generator.
When load management makes sense
It works well in homes with several large loads that rarely all need to run at the same moment, such as two AC systems, an electric dryer and a pool pump. It can let you power the whole house with a smaller generator than you would need otherwise. We tell you when it fits your home and when it does not.
When a larger generator is the better answer
If you want every AC unit running at full strength at once, or someone in the home relies on medical equipment that cannot wait, load management may not be enough. In that case a larger unit is the right call. We explain the tradeoff plainly so you can choose. Some homes use a larger generator and load management together, so the most important loads always have room.
Generac Generator Sizes and Your Electrical Service
The generator has to fit the house electrically, not just the list of appliances. Your service size and panel are part of the sizing.
What size Generac generator for 200 amp service
Many Houston homes have 200 amp service, and people ask what size generator matches it. The service size sets the transfer switch size, but it does not set the generator size. A home on 200 amp service may need an essentials unit or a full whole-home unit depending on its loads. We match the transfer switch to the service and the generator to the loads.
From smaller units to whole-home models
Generac's home standby line runs from smaller essentials units up to whole-home models in the 26 to 28kW range, with liquid-cooled units for larger homes. You can see the models we carry on our generator pages, including the 18kW, 22kW, 24kW, 26kW and 28kW units. The right model is the one that fits your loads, your service and your budget.
Panel condition and room for the transfer switch
An old, full or damaged panel can change the plan. Sometimes the panel needs work before a generator can be connected safely, and sometimes it makes sense to do a panel upgrade and generator install together. We check the panel on the sizing visit so there are no surprises on install day. If a panel upgrade is needed, it gets its own line on the estimate with the reason.
Fuel Supply and Placement Affect Generator Size
Sizing is not only about electricity. The fuel supply and where the unit sits have to work for the size you choose.
Natural gas meter and gas line size
A natural gas generator has to get enough gas while the furnace, water heater and stove may also be using it. The gas meter and the size and length of the gas line both matter. A larger generator may need a bigger meter or line. We check the gas side as part of sizing, and coordinate with the gas utility if the meter needs a change.
Propane tank size
If your home runs on propane, the tank has to supply the generator at the rate it needs and hold enough fuel for a long outage. A larger generator uses more fuel at full load. We talk through how long you want to run between refills and what tank setup fits your property. If you already have a propane tank, we check whether it can supply the generator or whether a change is needed.
Where the generator can go
A standby generator has to keep set distances from windows, doors and vents, and it needs room for service. Larger units have larger enclosures. On some lots the best spot limits the size that fits, so we look at placement before we finalize the recommendation. Placement also affects how far the gas line and wiring have to run, which matters for the install plan. We show you the spot we recommend and why before anything is set.
Getting Your Free Generator Sizing Estimate
The sizing visit is free, and it turns guesswork into a clear recommendation and a written estimate.
What we check on the visit
We look at your panel and service size, your AC units and their labels, your large appliances, your gas meter or propane tank and where the generator can sit. We ask what you want running during an outage and whether anyone relies on medical equipment. Then we recommend a size and explain why. You do not need to know your loads ahead of time. We do the math for you.
How to get ready
Make a list of what you cannot live without during an outage. Take photos of your panel label, your outdoor AC units and your gas meter. Text them to (713) 467-1125 and we can start before we arrive. Phones are open 24/7. If you have an HOA, check their rules on where a generator can sit and what approval they need, so it does not slow the project down later.
After the recommendation
You get a written estimate for the size we recommend, with the parts of the job listed. If you want to compare an essentials setup with a whole-house setup, ask and we will price both. We handle the permits, the install and the startup once you decide. If you want to think it over, take your time. The estimate spells out what is included so you can compare it with other quotes side by side.
Talk to us about your generator.
Estimates are free. Phones open 24/7.