Quick answer: A standby generator is a permanently installed backup power system that starts automatically during an outage and connects to the building through a transfer switch. In Charleston, the right system depends on what you need to keep running, your fuel source, and where the unit can be placed safely above flood risk and away from salt-air exposure.

Long outages after tropical storms are a fact of life in the Lowcountry. A standby generator turns an outage from an emergency into an inconvenience, but only when it is sized, connected, and placed correctly.

Portable vs. standby: which one fits?

Portable generators are lower-cost and flexible, but they require manual setup, refueling, and a safe connection method such as a transfer switch or listed interlock. They suit households that want to run a few essentials during occasional outages.

Standby generators are permanently installed, usually run on natural gas or propane, and start automatically when utility power is lost. They suit homes with medical equipment, home offices, and households that want hands-off protection, as well as businesses where downtime costs money.

Step 1: Decide what needs power

Generator sizing starts with a load list, not a brochure. Common approaches:

  • Essential circuits: Refrigeration, a few lights and receptacles, well or sump pumps, internet equipment, and medical devices. A smaller generator and a smaller transfer switch can cover these.
  • Whole-building backup: HVAC, water heating, cooking, and laundry. This requires a larger generator, and sometimes load-management controls that shed large appliances so the generator is not overloaded.

An electrician should perform a load calculation based on the actual equipment in the building. Air conditioning in a Charleston summer is often the deciding factor in system size.

Step 2: Choose the transfer method

The transfer switch is the part of the system that keeps you and utility workers safe. It isolates the building from the utility grid before generator power is connected, which prevents dangerous backfeed.

  • Automatic transfer switch (ATS): Senses an outage, starts the generator, and transfers the load with no action from you. Standard for standby systems.
  • Manual transfer switch or interlock: You start the generator and move the load yourself. Common with portable generators.

Optional standby systems are covered by the National Electrical Code, and installations require permits and inspections in Charleston-area jurisdictions.

Step 3: Pick a fuel source

  • Natural gas provides continuous fuel where gas service is available, with no refueling during a long outage.
  • Propane works where natural gas is not available, but tank size determines how long the system runs. Plan for refill access after a storm.
  • Diesel is common for larger commercial systems and requires fuel management and maintenance.

Gas piping and tank work involve additional trades and permits, so coordinate them with the electrical scope from the start.

Step 4: Place it for the Lowcountry

Placement matters as much as size:

  • Flood elevation. Set the generator and its electrical connections above expected flood levels. A generator sitting in floodwater fails exactly when you need it.
  • Clearances. Manufacturers and codes specify distances from windows, doors, vents, and property lines to control exhaust and fire risk.
  • Salt air. On the islands and near the water, ask about corrosion-resistant enclosures and a maintenance plan for terminations. See our guide to salt air and electrical equipment.
  • Noise and neighbors. HOAs and historic-district rules may affect where equipment can be located and how it is screened.

Step 5: Maintain it like the critical system it is

A standby generator that has not been maintained may not start when it is needed. A basic plan includes the manufacturer's automatic exercise cycle, periodic oil, filter, and battery service, and an inspection before hurricane season. Commercial systems that power emergency or life-safety loads have additional testing requirements.

Commercial standby power

For businesses, start with a list of loads that cannot go down: refrigeration and freezers, servers and phone systems, security systems, sump and lift pumps, and point-of-sale. Some facilities need separate emergency or legally required standby systems that follow stricter rules than optional backup power. An early conversation with your electrical contractor and engineer avoids redesign later.

Frequently asked questions

How big of a generator do I need for my Charleston home?

It depends on what you want to run. Powering essential circuits requires a much smaller generator than whole-home backup with central air conditioning. A load calculation by a licensed electrician based on your actual equipment is the reliable way to size it.

Do I need a transfer switch for a generator?

Yes. Any generator connected to building wiring needs a transfer switch or a listed interlock so it cannot backfeed utility lines. This protects utility workers, your neighbors, and your equipment.

Do I need a permit to install a standby generator in Charleston?

Yes. Standby generators require electrical permits and inspections, and gas or propane connections typically require additional permits. Your contractor should handle permitting with the correct jurisdiction.

Where should a generator go on a property in a flood zone?

Above expected flood levels and at the clearances required by the manufacturer and code. Elevated pads or platforms are common in low-lying parts of the Lowcountry.

Planning backup power for a home or business? Request an estimate or call Copperhead at 854-444-6516.