What size generator does your home actually need?

The most common question we get, and the most common mistake we see. The short version: a generator that's too small will shed the loads you care about or stall under startup surge — and one that's too big costs thousands more up front, burns more fuel, and runs less efficiently for the life of the unit. Right-sized is the goal.

It's about your loads, not your square footage

Two houses with the same square footage can need very different generators. What matters is what's drawing power: central A/C is almost always the biggest factor, followed by things like a well pump, electric water heater, electric range, or a shop out back. Air conditioners and pumps also pull a brief surge when they start — several times their running draw — and the generator has to handle that moment, not just the steady state.

What a load calculation looks like

When we quote a whole-home system, we walk the house and add it up:

• The must-runs: A/C or heat, refrigerator and freezer, well pump, lights, and anything medical.
• The startup surges: compressor and motor loads, and whether smart load management can stagger them instead of paying for peak capacity.
• The nice-to-haves: the second A/C unit, the pool pump, the shop — things you can choose to include or leave on a managed circuit.

That's how the same house might quote at 18kW with load management or 26kW without — and why a quote over the phone without seeing the panel is a guess.

Where people go wrong

Buying on price per kW. A bigger unit on sale isn't a deal if it short-cycles at low load for twenty years. Copying the neighbor. Their loads aren't yours. Forgetting the panel. An older panel may need work before any generator connects safely — better to know that up front, in the quote, than mid-install.