Generac GP8000E

Generac's big-box staple for whole-essentials backup.

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Specs

Running watts	8,000 W
Starting watts	10,000 W
Type	Open frame
Fuel	Gasoline
Fuel tank	7.5 gal
Runtime (mfr claim)	~11 h at 50% load
Outlets	Two 20A 125V GFCI, L14-30R (transfer switch), 120/240V
Start	Electric
CO safety shutoff	Varies by version — check the listing
Typical street price	~$1,150 (as of July 2026 — check listing for current price)

Figures are the manufacturer's published specs; dashes mean the maker doesn't publish a number. Verify against the current datasheet before you buy.

What can it actually run?

Checked with the same math as our calculator: total running watts, plus the single largest motor surge on top. “Tight” means it technically fits but the load sits above 80% of rated output — fine briefly, not where you want to live.

Fridge, Wi-Fi, and lights
730 W running · 2,230 W peak
✓ runs it
Storm essentials (fridge, freezer, furnace fan, sump pump)
3,080 W running · 4,670 W peak
✓ runs it
Essentials plus a 10,000 BTU window AC
4,280 W running · 6,680 W peak
✓ runs it
Most of the house (well pump, central AC, laundry)
13,680 W running · 35,930 W peak
✗ too much

The installer's take

The GP series is what half of suburbia buys after their first multi-day outage: 8 kW running, a 10 kW surge that shrugs off a well pump start, and a 7.5-gallon tank that runs most of a day at half load. Parts and service are easy because everyone stocks Generac. It is exactly as loud as it looks.

Pros

10,000W surge handles well pumps and AC compressors
Ubiquitous parts and service network
Full-day runs on one tank at moderate load

Cons

Open-frame loud
Gasoline only — no propane fallback

Best for: Well-pump households and anyone standardizing on the most common service network.

Check it against your appliances →

Don't forget the consumables

Whatever you buy needs oil every 50-100 running hours, stabilised fuel if it sits between outages, and a CO alarm indoors. Cheap, and the reason a stored generator either starts or doesn't.

All accessories & consumables →

Compare it

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