Outage Sizer

What will it run / 5,000 W

What will a 5,000 watt generator run?

Taking the Westinghouse iGen5000 as the example: it is rated 3,900 W running and 5,000 W peak. In this site's outage order it carries 8 kinds of load at once — 2,793.2 W running, with room to start the biggest motor in the list for a total of 4,993.2 W — and it can start 26 of the 30 devices in the tables on their own.

Running rating
3,900 W
Peak rating
5,000 W
Surge room at full load
1,100 W
Starts alone
26 of 30
Refrigerator/freezer ×1: 700 WSump pump, 1/2 hp ×1: 1,050 WFurnace fan blower, 1/3 hp ×1: 700 WCPAP machine (ResMed AirSense 11) ×1: 73.2 WLED light bulb, 15 W ×6: 90 WCell phone charger ×2: 40 WTelevision, LED ×1: 80 WLaptop ×1: 60 WRunning 2,793.2 W+ 2,200 W start = 4,993.2 Wrunning rating 3,900 Wpeak rating 5,000 W
What the Westinghouse iGen5000 carries in this site's outage order, to scale. Each block is one load's running watts; the cap is the biggest starting surge.

Westinghouse sells the iGen5000 on its 5,000 W peak figure; its running rating is 3,900 W. That gap of 1,100 W is the room it has for a starting surge once the running load reaches its rating.

Westinghouse lists 18 hours of run time at 25% load from its 3.4-gallon tank.

An outage list it can carry

LoadQtyRunning WExtra to start
Refrigerator/freezer17002,200
Sump pump, 1/2 hp11,0502,150
Furnace fan blower, 1/3 hp17001,400
CPAP machine (ResMed AirSense 11)173.2—
LED light bulb, 15 W690—
Cell phone charger240—
Television, LED180—
Laptop160—
Total2,793.2+ 2,200 = 4,993.2

The list is filled in a fixed order — refrigerator, sump pump, furnace fan, well pump, CPAP, lights and chargers, then television, laptop, microwave, coffee maker, space heater and window air conditioner — skipping anything that would push the running total past 3,900 W or the starting total past 5,000 W. It leaves 1,106.8 W of running capacity and 6.8 W of starting capacity unused. The highlighted row has the biggest starting surge, which is the one added to the running total.

What it can start on its own

Refrigerator/freezer; Sump pump, 1/3 hp; Sump pump, 1/2 hp; Well pump, 1/3 hp; Well pump, 1/2 hp; Furnace fan blower, 1/3 hp; Furnace fan blower, 1/2 hp; Garage door opener, 1/2 hp; Microwave, 1,000 W; Coffee maker; Toaster; Toaster oven; Air fryer; Slow cooker; Electric range, one 8-inch element; Dishwasher; Washing machine; Space heater; CPAP machine (ResMed AirSense 11); Oxygen concentrator (Philips EverFlo); LED light bulb, 15 W; Television, LED; Laptop; Desktop computer with monitor; Cell phone charger; AM/FM radio.

Too big even alone: Window air conditioner, 12,000 BTU (7,200 W to start); Central air conditioner, 24,000 BTU (2 ton) (8,750 W to start); Heat pump (9,200 W to start); Electric water heater (4,500 W to start).

A refrigerator and a 1/2 hp sump pump together need 1,750 W running and 3,950 W to start — within this generator's ratings.

Compared with the other sizes

Honda EU2200i1,800 / 2,200 WHonda EU3000iS2,800 / 3,000 WWestinghouse iGen50003,900 / 5,000 WHonda EU7000iS5,500 / 7,000 WChampion 2010407,500 / 9,375 WWestinghouse WGen9500DF9,500 / 12,500 W
Peak (bar length) and running / peak ratings of the six portables this site covers, from each maker's page.

Run time: 18 hours at 25% load from a 3.4-gallon tank, by the maker's figures. Keep it outdoors at least 20 feet from doors, windows and vents (why).

Ratings: Westinghouse, iGen5000 inverter generator. Appliance figures: Generac GP brochure, EWEB and Champion tables (see methodology). Other sizes: 2,200 W · 3,000 W · 7,000 W · 7,500 W · 9,500 W.