Standby Generator Size Estimator
Answer a few questions to get a ballpark kilowatt range for your home — no contact info required to see your result.
What do you want backed up?
Standby Generator Size Reference
A quick reference for common backup scopes in northern New Hampshire and Vermont. Your real number depends on an on-site load calculation.
| Backup Scope | Ballpark Size | What It Covers |
|---|---|---|
| Essentials only | 10–14 kW | Heat, well pump, fridge, some lights |
| Most of the house | 18–22 kW | Most circuits, typical North Country home |
| Everything | 22–26 kW | Whole-home backup |
| Everything + electric heat | 26 kW+ or load management | All-electric home, whole-home backup |
Ranges are estimates for planning only. Actual sizing requires a load calculation.
Generator Sizing — Frequently Asked Questions
How accurate is the generator size estimator?
It gives you a ballpark range based on what you want backed up, your heat source, and your home size. The right size comes from an on-site load calculation, which we do before quoting.
What's the difference between essentials and whole-home backup?
Essentials backup covers critical circuits like heat, a well pump, the fridge, and some lights. Whole-home backup is sized to carry your entire electrical load so everything stays on.
Why does my heat source matter for generator sizing?
Electric baseboard and heat pumps draw a lot of power, so an all-electric home needs a larger generator than one heated with an oil or propane furnace or boiler.
Do standby generators run on propane?
Most of the standby units we install in the North Country and Northeast Kingdom run on propane, which is already piped to many homes up here. We connect the generator to your existing fuel supply.
Does a bigger home always need a bigger generator?
Often, but not always. What matters most is what you want backed up and the starting load of your largest motors. A large home backing up only essentials can get by with a smaller unit than a modest all-electric home backing up everything.
Serving Colebrook & the Surrounding Region
From our shop at 12 NH Rte 145, Colebrook, NH 03576, we install and service standby generators across northern New Hampshire's North Country and Vermont's Northeast Kingdom.
Learn about our generator services →Ready When You Are
Tell us about your project or call the shop — we'll take it from there.