Typical prices
| Job | Typical Long Island range | What drives it |
|---|---|---|
| Whole-house standby generator (installed) | $8,000 – $16,000 | Typical Generac whole-house system: unit, pad, automatic transfer switch, gas connection, permit. Larger 22–26 kW units and long gas runs sit at the top. |
| Smaller standby (7.5–10 kW, essential circuits) | ~$5,000 – $8,000 | Powers a sub-panel of essential loads rather than the whole house. |
| Portable generator inlet + interlock | Usually far below a standby system | Code-compliant way to run household circuits from a portable generator. Never back-feed through a dryer outlet. Get a written quote. |
| Gas line extension | Varies widely | Done by a licensed plumber. Distance from the gas meter and meter size drive it. |
These are national and manufacturer-dealer ranges; we haven't found a reliable Long Island-specific source yet. Expect Nassau and Suffolk labor and permitting to sit at or above them. Ask for an itemized written quote.
What moves the price
- Size (kW): whole-house with central air needs a much larger unit than essential circuits.
- Gas run: distance from the gas meter, and whether the meter needs upsizing.
- Transfer switch: whole-house automatic switches cost more than an essential-loads sub-panel.
- Placement: clearances from windows and lot lines, and elevation in flood zones.
- Panel condition: an old or full panel may need replacing first (panel upgrade cost).
Never back-feed
Plugging a portable generator into a dryer outlet or any receptacle can energize the utility lines and kill a lineworker, and it can start a fire. Use a listed inlet with an interlock or a transfer switch, installed by a licensed electrician and inspected by an approved agency. More: generator installation on Long Island.
Frequently asked questions
Natural gas or propane?
Natural gas is the usual choice where it's available, since there's no tank to refill. Propane is common in parts of Suffolk without gas mains and needs a tank sized for multi-day outages.
How long does installation take?
The on-site work is often one to three days, but permits, gas work and inspection scheduling stretch the total. Book well before hurricane season if you can.
Do standby generators need maintenance?
Yes: periodic oil and filter changes, battery checks and exercise runs. Many installers sell annual maintenance plans.