What is a standby generator?

What this means for your home project

1. Read the intended backup appliances’ manuals or data plates and record their wattage requirements for the sizing discussion. Source: City of Tallahassee Utilities, read 2026-11-04.
2. Draw a schematic identifying appliances and equipment that need temporary power, so the proposed backup loads are explicit. Source: DOE / Pacific Northwest National Laboratory, read 2026-11-04.
3. Request a written site-work scope identifying excavation, soil compaction and concrete-pad work for the generator and any fuel tank, so those tasks are itemized. Source: DOE / Pacific Northwest National Laboratory, read 2026-11-04.
4. Ask the seller to identify applicable installation or operation permits in its written reply, so the permit scope is explicit. Source: City of Tallahassee Utilities, read 2026-11-04.

What is the difference between standby and portable generators?

The practical difference is setup during an outage: a portable unit typically supplies individual appliances through extension cords, while a standby system uses an automated transfer switch. Tallahassee’s utility describes portable units as typically gasoline-fueled; its standby guidance discusses natural gas or propane. “Portable generators supply electricity to selected appliances through extension cords and are typically fueled by gasoline, which can be difficult to obtain, store and transport during an emergency situation.” Source: City of Tallahassee Utilities, read 2026-11-04. “Unlike a portable generator, the transfer switch is completely automated; you do not need to activate any switches.” Source: City of Tallahassee Utilities, read 2026-11-04. “Because standby generators run on natural gas (or propane in areas without natural gas service), you don't need to find and transport gasoline to power the unit.” Source: City of Tallahassee Utilities, read 2026-11-04.

What components and features come with a standby generator?

The automatic transfer switch changes the home’s power connection from utility service to the generator. The engine can use air cooling or liquid cooling. Tallahassee’s utility suggests considering liquid cooling for large homes, several air conditioners, or other substantial power needs. “When it detects a service issue, the automatic transfer switch (ATS) will safely disconnect the utility service provider's power and connect to the generator's power.” Source: City of Tallahassee Utilities, read 2026-11-04. “The engine in a standby generator can be cooled by air or liquid.” Source: City of Tallahassee Utilities, read 2026-11-04. “If you have a large home, multiple air conditioning units (either window or central air), several large appliances or medical equipment that needs constant power, you might want to consider a liquid-cooled model, which will provide backup power for the whole house and light commercial applications.” Source: City of Tallahassee Utilities, read 2026-11-04.

How should I choose my standby generator's wattage?

Choose capacity around the appliances and circuits you want to run, including their starting demand. Running wattage describes electricity needed during operation; surge wattage describes the higher demand when motors start. The city utility recommends checking appliance manuals or data plates for the calculation. “The more circuits and appliances you want to power, the more wattage you'll need.” Source: City of Tallahassee Utilities, read 2026-11-04. “Most appliances are rated for running wattage (the amount of electricity necessary to run the appliance) and surge wattage (the higher amount of electricity needed to start electric motors commonly found in household appliances, such as central air conditioning or refrigerators).” Source: City of Tallahassee Utilities, read 2026-11-04. “To accurately tabulate your wattage requirements, check the appliances' user manuals or the data plate on the back of the appliance.” Source: City of Tallahassee Utilities, read 2026-11-04.

What should I budget for a standby generator?

Build the budget around equipment, installation, permit applications and fuel supply. Those are the cost factors identified by Tallahassee’s utility. For permanent systems, PNNL also identifies excavation, soil compaction and a concrete pad as site work to include in the proposed scope. “The cost of a standby generator depends on several items, including the basic equipment, installation, permit applications and fuel source.” Source: City of Tallahassee Utilities, read 2026-11-04. “Locate and mark a site for the generator and fuel tank, including excavation and compaction of the soil and construction of a concrete pad.” Source: DOE / Pacific Northwest National Laboratory, read 2026-11-04.

Where should I locate my standby generator?

Check placement before selecting the installation site. Brookline, New Hampshire’s undated notice quotes NFPA 37 section 4.1.4 with a 5-foot separation rule and exceptions; PNNL recommends 20 feet from the home. These captured distances differ. Ask the installer and local authority to resolve current code and model instructions before siting the unit. “A standby generator should always be positioned in a well-ventilated outdoor space and never next to a window, door or fresh air intake due to potentially harmful carbon monoxide exhaust.” Source: City of Tallahassee Utilities, read 2026-11-04. “Engines, and their weatherproof housings if provided, that are installed outdoors shall be located at least 1.5 meters (5 feet) from openings in walls and at least 1.5 meters (5 feet) from structures having combustible walls.” Source: Town of Brookline, New Hampshire, read 2026-11-04. “A 5 foot minimum separation shall not be required where the following conditions exist: (1) The adjacent wall of the structure has a fire resistance rating of at least 1 hour.” Source: Town of Brookline, New Hampshire, read 2026-11-04. “(2) The weatherproof enclosure is constructed of noncombustible materials and it has been demonstrated that a fire within the enclosure will not ignite combustible materials outside the enclosure.” Source: Town of Brookline, New Hampshire, read 2026-11-04. “Keep the generator at least 20 ft from the home.” Source: DOE / Pacific Northwest National Laboratory, read 2026-11-04.

Should I install a standby generator myself?

Plan for professionals to handle electrical and gas connections and the applicable permitting. Tallahassee’s utility describes that division of work even when an owner places or mounts components. Separately, PNNL calls for electrical isolation from the grid to protect utility workers; this is part of the connection design. “Some utility customers take the initiative to place and mount the various components but rely on professionals for electrical and gas connections, as well as the proper permitting.” Source: City of Tallahassee Utilities, read 2026-11-04. “All home power generation requires strict disconnect controls to isolate the home generation system from the grid to ensure the safety of utility workers.” Source: DOE / Pacific Northwest National Laboratory, read 2026-11-04.

Sources

• Natural Gas | Generators — City of Tallahassee Utilities; read 2026-11-04.
• Generators for Back-Up Power During Outages — DOE / Pacific Northwest National Laboratory; published 2021-09-30; read 2026-11-04.
• Notice: Standby Generator Installations — NFPA 37 section 4.1.4 — Town of Brookline, New Hampshire; read 2026-11-04.