Panel Upgrades and Standby Generators in Texas: What to Know Before You Hire
What Texas homeowners should know about panel and service upgrades and standby generators: load calcs, transfer switches, permits and who does the work.
Why Texans are thinking about backup power
The February 2021 winter storm, often called Winter Storm Uri, changed how many Texans think about home power. A Texas Comptroller report cites survey data finding that 69 percent of Texans lost power at some point from February 14 to 20, 2021, for an average of 42 hours. Since then, many homeowners and small businesses have looked at standby generators, and many are adding EV chargers, heat pumps and other large loads. Both trends lead to the same question: can the existing electrical panel and service handle it?
Panel upgrade vs. service upgrade
These terms are often mixed up:
- Panel replacement. This swaps an old, full or unsafe breaker panel for a new one. It may add breaker spaces without increasing the total power available to the house.
- Service upgrade. This increases the capacity of the service, the conductors and equipment that bring power from the utility. It usually involves new service-entrance equipment and coordinating a disconnect and reconnect with your utility.
- Subpanel. This adds breaker spaces in a convenient location, such as a garage, fed from the main panel. It does not add capacity.
Whether you need any of these should come from a load calculation under NEC Article 220, not a rule of thumb. In some cases, load-management equipment that limits a charger or other large load lets you avoid a service upgrade. Ask your electrician to compare the options.
Standby generators: how they connect
A permanently installed standby generator is usually fueled by natural gas or propane and starts automatically when utility power fails. Under the National Electrical Code, a generator that supplies a building's wiring must connect through transfer equipment that keeps the generator and the utility from being connected at the same time. Otherwise, generator power could backfeed into utility lines and endanger line workers. This is covered by Article 702 (optional standby systems) for most homes.
Decisions your contractor should walk you through:
- Whole-house or selected circuits. A generator sized for the whole house can run everything, while a smaller unit powers only the essential circuits wired to the transfer switch.
- Automatic or manual transfer. Automatic switches start the generator and transfer the load without anyone at home.
- Load management. Many systems can shed large loads such as air conditioning or an EV charger so a smaller generator is not overloaded.
- Placement. The manufacturer's clearances from windows, doors, vents and property lines, plus local rules, decide where the unit can sit.
Permits and who does what
Generator and panel work is electrical work under Texas law, so it should be done by a TDLR-licensed Electrical Contractor. Cities typically require permits and inspections. In Houston, for example, the Houston Permitting Center's generator permit page says registered electrical contractors must apply for an electrical permit, which is issued only to registered master electricians, and plan review may be required.
The fuel side is separate. Gas piping in Texas falls under plumbing licensing overseen by the Texas State Board of Plumbing Examiners, so a gas-fueled generator usually involves a licensed plumber and may need its own permit. Many generator installers coordinate both trades. Ask who is responsible for each part and each permit. Propane installations may also involve the propane supplier.
Portable generators: safety basics
If you use a portable generator instead, never plug it into a household outlet to backfeed the house. Connect it through a properly installed transfer switch or interlock, or run extension cords to individual appliances. The CDC advises running generators only outdoors, more than 20 feet from windows, doors and vents, and installing battery-powered or battery-backup carbon monoxide detectors.
Before you sign
- Verify the contractor's Electrical Contractor license on the TDLR license search and ask for a certificate of insurance.
- Ask for the load calculation and a written list of the circuits the generator will power.
- Confirm who pulls the electrical permit and any gas permit, and who schedules utility coordination.
- Get the manufacturer's warranty and maintenance requirements in writing. Standby generators need periodic exercise and service, and a unit that has not been maintained may not start when you need it.
- If you also plan to add an EV charger, say so up front so the panel, the service and the generator's load management are planned together.