What size generator do I need to run a cabin?

A small 1-2BR cabin with a well pump and heat pump needs at least 14kW. A larger 3-4BR cabin with central HVAC and electric heat strips needs 22 to 26kW. The well pump HP and heat strip kW rating are the two variables that matter most, not square footage alone.

What is the 80% rule for generators?

The 80% rule means you should not load a generator beyond 80% of its rated capacity for continuous operation. A 20kW generator should carry no more than 16kW of sustained load. This is an industry best practice for optional standby systems that protects the generator from overheating during extended outages.

Can a generator run a well pump and air conditioner at the same time?

Yes, but you must size for the startup surge of both. A 1 HP well pump surges to 3,750-5,000W at startup depending on pump type, and a 2-ton heat pump compressor surges to 4,000 to 6,000W. If both start simultaneously (which a standby generator's automatic transfer switch can trigger), you need enough capacity to handle both surges. A 14kW or larger generator handles this for most mountain cabin configurations.

Do I need a permit to install a standby generator in Fannin County, GA?

Yes. Fannin County requires a building permit for standby generator installations. The permit covers the gas piping (propane), electrical connections, and transfer switch. An electrical inspection is required before the system is energized. FTH pulls the permit and coordinates the inspection as part of every installation.

What size house will a 22kW generator run?

A 22kW generator covers a 2,000 to 3,000 square foot home with central HVAC, a well pump up to 1 HP, electric heat strips up to 7.5kW, and standard household circuits. For a North Georgia mountain cabin, 22kW is the sweet spot for a 3-4BR property with full HVAC and a well pump.

Is a portable generator good enough for a mountain cabin?

For a weekend cabin where you're on site during outages, a portable generator can run essential circuits. But for out-of-state owners or STR properties, a portable generator is not practical. It requires manual startup, refueling, and cannot power a whole house. A standby generator starts automatically within 10 to 30 seconds of a power loss, runs on a plumbed propane tank, and requires no one on site.

Standby Generator Sizing for a North Georgia Cabin