Generators generate questions faster than electricity. These are the ones homeowners actually ask in forums — how big, how loud, how much fuel, how to connect one without backfeeding a line crew — each answered with specs, checked prices, and the math shown. The short answer is under every question; the full workings live on each question’s own page where one exists. This shelf hangs off our Power hub, next to the scored generator and station comparisons.
Sizing questions
How big a generator do I need for a 1,000 sq ft house?
Square footage is the wrong unit — the load list is the right one. A typical 1,000 sq ft house’s essentials (fridge, furnace blower, sump pump, lights, phones) run about 1,500–2,000 watts, with worst-minute starting peaks around 2,600 watts — higher with a well pump — which lands most houses in the 3,500–5,000 watt inverter-generator band.
What size generator runs a well pump?
Size it to the pump’s starting surge and its voltage, not its running watts: a 1/2 hp pump needs about 2,000–2,500 starting watts, a 1 hp about 4,000–5,000 — and most pumps over 1/2 hp run on 240V, which puts most well houses in the 5,000–7,500 watt class with a 240V outlet and a transfer switch.
What’s the best generator for home? If you’ve been through a multi-day outage, what wattage ended up being the sweet spot?
Two sweet spots cover most houses: about 2,000 watts of inverter generator if the job is fridge, lights, and phones; 5,000–7,500 watts if a well pump or furnace has to start too. Owners who bought by the first number and needed the second are the ones posting the question the next storm.
Covered in: Best solar generators for home backup compared
Inverter generator or regular — does it matter for a house?
For anything with a circuit board, yes. Conventional generators can run 15–25% total harmonic distortion; inverters hold it under about 3%, which is the “clean power” line electronics are built for. Inverters are also quieter and sip fuel at partial load — and cost more per watt, which is the honest trade.
Covered in: Best solar generators for home backup compared
1,000 sq ft house: Square footage is the wrong unit — the load list is right: essentials run about 1,500–2,000 W, worst-minute peaks around 2,600 W, landing most houses in the 3,500–5,000 W inverter band.
Well pump: Size to starting surge and voltage: a 1/2 hp pump needs about 2,000–2,500 starting watts, a 1 hp about 4,000–5,000 — and most over 1/2 hp run on 240V, putting well houses in the 5,000–7,500 W class.
The two sweet spots: About 2,000 W of inverter generator for fridge, lights, and phones; 5,000–7,500 W if a well pump or furnace has to start too.
Inverter or regular? Conventional generators can run 15–25% total harmonic distortion; inverters hold it under about 3% — quieter, sip fuel at partial load, and cost more per watt.
Hookup questions
Transfer switch, interlock, or extension cords?
Cords are the $0 answer that powers two or three things through a cracked door. An interlock kit (typically $150–$250 plus an electrician’s hour or two) lets a portable generator run chosen circuits through your panel, legally. A transfer switch costs more and does the same job with less to remember. What none of them may ever do is backfeed a dryer outlet — that is how line workers get hurt.
Can a gas generator recharge a home battery like a Powerwall?
Usually, no — and it’s the answer owners least expect. Tesla does not support charging a Powerwall from a portable generator, and most wall batteries are the same; the supported routes are the grid, solar, or a properly integrated standby unit. Big portable stations are the exception: most will happily charge from a generator, which is why the station-plus-generator setup below exists.
Extension cords: The $0 answer: powers two or three things through a cracked door.
Interlock kit: Typically $150–$250 plus an electrician’s hour or two — a portable generator runs chosen circuits through your panel, legally.
Transfer switch: Costs more and does the same job with less to remember.
Charging a Powerwall? Usually no — Tesla does not support charging a Powerwall from a portable generator. Big portable stations are the exception: most charge happily from one.
Never an option: None of these may ever backfeed a dryer outlet — that is how line workers get hurt.
The setup questions
Automatic backup without solar: a power station the generator recharges
The station carries the house silently and switches on instantly; the generator is demoted to a battery charger that runs a few loud hours a day instead of all day. For a house burning 4–6 kilowatt-hours a day — furnace blower, sump pumps, fridge, lights — that works out to roughly 3–4 hours of generator time daily.
Portable or standby generator — is standby worth the cost difference?
A standby installation typically lands around $12,000–$15,000 all-in; a good portable setup is $1,000–$2,000 plus you, outside, in the rain, starting it. Standby buys automatic, whole-house, no-one-home coverage. The math turns on outage frequency and whether anyone is home to run the portable — not on the machines themselves.
Covered in: Best solar generators for home backup compared
Fuel and ownership questions
Generator fuel: how much does one burn a day, how much should I store, and how do I keep it from going stale?
A mid-size generator at half load burns roughly half to three-quarters of a gallon an hour — call it 10–15 gallons for a full day of running, which is why the recharge setup above matters. Untreated gasoline is a 3–6 month fuel; with stabilizer, about a year. Rotate it through a car, not into a corner of the garage to be forgotten.
Standby generator bids: placement, load managers, and how to check what you’re paying for
Start with the clearances, because they decide where the unit can even go: manufacturers typically want about 5 feet from windows, doors, and vents, and the exhaust pointed away from the house. Then read the bid for the quiet line items — a load manager is how a smaller (cheaper) unit pretends to be a bigger one, and it should be priced and named, not buried.
How do I stop a standby generator running through a planned outage?
On most standby units (Generac included), the answer is one switch: move the controller from AUTO to OFF before the planned outage and back to AUTO after — the generator then sits it out with you instead of burning propane all night. The two exceptions where you should let it run: a sump pump guarding a wet basement, and medical equipment.
Burn rate: A mid-size generator at half load burns roughly half to three-quarters of a gallon an hour — about 10–15 gallons for a full day of running.
Gasoline life: Untreated gasoline is a 3–6 month fuel; with stabilizer, about a year. Rotate it through a car, not into a corner of the garage.
Reading a standby bid: Manufacturers typically want about 5 feet from windows, doors, and vents, exhaust pointed away — and a load manager should be priced and named in the bid, not buried.
A planned outage: On most standby units, move the controller from AUTO to OFF before the outage and back to AUTO after — except a sump pump guarding a wet basement, and medical equipment.
How we answer
Ordinary Prepper is a research desk, not a test lab: we do not claim hands-on testing. Answers come from manufacturer specifications, prices checked on the date shown, and owner feedback counted in the open. When a number is a typical range rather than a spec, the answer says so.