What Size Standby Generator Do You Need? A Minnesota Sizing Guide
“What size generator do I need?” is the question we hear most about backup power — and the one most likely to be answered wrong online. Too small and it can’t carry your home; too big and you overpaid. Here’s how sizing actually works for a Minnesota home.
Start with what you want to power
Generator sizing isn’t about your home’s square footage — it’s about the loads you want to run during an outage. There are two common goals:
- Essentials only: furnace/blower, well pump, sump pump, fridge/freezer, and some lights and outlets.
- Whole-home: everything, including central AC and electric appliances, so an outage feels like nothing happened.
The Minnesota-specific loads
Our winters put a few big items at the top of the list:
- Furnace blower — small running watts, but essential for heat
- Well pump and sump pump — big starting surges that a generator must handle
- Freezer/fridge — protecting food over a multi-day outage
Those motor start-up surges are exactly why a proper load calculation beats a rule of thumb.
How we size it right
We add up your running watts, account for the largest starting surge, and factor in fuel type and future plans. That points to a standby unit — commonly in the 18–26 kW range for whole-home coverage, smaller for essentials. Our generator sizing process removes the guesswork.
Don’t forget the transfer switch
The automatic transfer switch is sized alongside the generator and determines which circuits are covered. Getting the pairing right is as important as the generator itself.
Right-sized, not oversold
We size for your home and your priorities — not the biggest unit on the shelf. Three Rivers Electric — Generator-certified, licensed (EA761814), veteran-owned, 5.0★, serving the Twin Cities Metro. Explore generator services, then request a free quote or call 651-418-1476.
