When the power goes out in Gilbert, keeping the lights on is only part of the equation. You also need enough backup power for refrigeration, medical equipment, internet service, garage doors, pool equipment, and, most importantly, air conditioning, especially when the temps top 100.
What size generator do I need for my house? The answer depends on which equipment must operate, its electrical demand, and whether several large appliances may start together. A professional load calculation helps avoid buying unused capacity or installing a unit that cannot meet your needs.
Start With the Equipment You Want to Back Up
Some Gilbert homeowners only want essential-load coverage, while others want nearly normal whole-home operation. Your first decision is about what goes on your must-have list, such as:
- Refrigerator and freezer
- Lights in key rooms
- Internet equipment and device chargers
- Garage-door opener
- Medical or security equipment
- Selected kitchen outlets
- One air-conditioning system
You may also prefer whole-house backup that includes cooking appliances, laundry equipment, pool pumps, multiple HVAC systems, and water heaters. Keep in mind, though, that the more equipment expected to run simultaneously, the more capacity may be needed, and the higher the cost will be.
Understand Running and Starting Wattage
Every electrical device has a running wattage, which is the power it uses during normal operation. Equipment with a motor or compressor also has a higher starting wattage, a temporary surge when equipment such as an air conditioner, refrigerator, or pool pump starts up.
A generator must be able to handle both the continuous load and these brief startup demands. Simply adding the running wattage shown on appliance labels likely underestimates the capacity you really need. An electrician should evaluate the largest motor loads, the likelihood that they will start together, and the generator’s load-acceptance capability. FYI, your AC’s compressor is typically one of your home’s largest loads.
Give Air Conditioning Special Attention
Generator sizing for an HVAC system depends on more than the air conditioner’s tonnage. The calculation may consider voltage, amperage, compressor type, efficiency, startup requirements, and whether the home has one system or multiple units.
Generac’s current air-cooled standby-generator line ranges from 10 to 28 kW. The 28 kW model provides up to 28,000 running watts and is designed with enough load-acceptance capability to start and run most five-ton air-conditioning units. Your home in Gilbert may not need a model that big; many homes can use a smaller generator.
Generac also offers integrated thermostat and HVAC energy-management technology, which can coordinate cooling loads during an outage, optimize HVAC operation, and help prevent the generator from becoming overloaded. Strategic load management might also let you support cooling equipment without sizing the generator for every large load to operate at once.
Decide Between Essential-Load and Whole-House Coverage
When asking what size generator do I need for my house, consider how you want life to function during an extended outage. An essential-load system powers selected circuits to preserve food, maintain communications, operate critical devices, and potentially keep one cooling system running.
A whole-house system supplies a broader range of circuits through an automatic transfer switch. However, “whole-house” does not always mean every electrical device can run simultaneously without limits. A home with electric water heating, multiple air conditioners, an electric range, a clothes dryer, a pool pump, and EV charging can have substantial demand. So, your sizing plan should reflect realistic priorities during an outage.
Factors That Can Change the Calculation
Two Gilbert homes with similar square footage may require different generator sizes. Important variables include:
- The number and size of HVAC systems
- Gas versus electric appliances
- Pool, spa, or well-pump loads
- Electric water heating
- EV charging equipment
- Home additions or detached structures
- Medical equipment and other critical loads
- Plans for future electrical upgrades
Fuel supply also matters. A standby generator needs the correct natural-gas volume and pressure or an adequately sized propane supply.
Avoid Sizing a Generator by Square Footage Alone
Online charts may estimate generator capacity based on home size, but square footage doesn’t consider your home’s actual electrical demand. A smaller all-electric home can require more backup capacity than a larger home with natural-gas appliances. Likewise, two identical houses may have very different needs if one homeowner wants only essential circuits and the other expects full-home convenience.
The best answer comes from a site-specific load calculation. A qualified electrician can review the electrical panel, measure or calculate major loads, identify startup demands, discuss which circuits matter most, and determine whether load management can reduce the required generator capacity.
So, What Size Generator Do I Need for a Home in Gilbert?
Figuring out what size generator you need for your home is a balancing act. An undersized system may overload or force you to shut down important equipment, while an oversized unit can add unnecessary costs.
George Brazil Plumbing & Electrical can evaluate your home’s electrical loads, cooling requirements, fuel source, and backup priorities. Schedule an in-home assessment with George Brazil to get a recommendation and quote for the right Generac generator for your Gilbert home.