How Long Do Home Generators Last?
Most home generators last 1,000 to 2,000 running hours if they're petrol, and far longer if they're a serviced diesel. How many years that is depends on your use, so here's how to work out yours.
Generator Lifespan in Running Hours
Engine wear is counted in running hours. That's the number to watch, and it's why so many generators show hours on the panel.
Petrol Portable and Inverter Generators
Thompson Power, an Australian generator hire company, puts petrol generators at 1,000 to 2,000 hours. US fuel supplier Petro gives portable generators up to 2,000 total hours.
Both are rough guides, and Thompson says consumer generators built for home use may only last a few years. A quality engine that's serviced on time sits at the top of that range. A cheap one that's flogged or neglected sits at the bottom, or below it.
Diesel and Standby Generators
Thompson gives diesel generators 15,000 to 50,000 hours, and says commercial backup generators typically last 20,000 hours or more, which it works out at 15 to 30 years with proper maintenance.
Those figures are for commercial and industrial sets. A small portable diesel isn't the same machine, so treat them as the ceiling, not the expectation. The fuel trade-offs are in petrol vs diesel generator.
Why Makers Don't Print a Number
You won't find a lifespan in most generator manuals. Queensland's Electrical Safety Office suggests asking the supplier for the expected usage before engine overhaul, in years, since a long period before overhaul may involve considerable extra cost.
What makers do commit to is a warranty. The Westinghouse generator warranty runs two years or 500 operating hours for domestic use, whichever comes first.
A warranty isn't a lifespan, but it's the one figure a maker stands behind. When you compare two machines, check the hours cap as well as the years.
Turning Hours Into Years
An hour meter makes this easy. The Westinghouse iGen2250 shows cumulative run time on its display, and the Westinghouse WHXC8500E has a panel meter showing run hours.
Blackout Backup at Home
A home backup generator does very few hours. Westinghouse asks for a monthly run of 30 minutes, which is six hours a year. Add a few blackouts and you might reach 40 hours a year.
At that rate 2,000 hours is decades away, so for backup at home the hours rarely end its life. The way it sits between runs does, which we cover below.
No hour meter on yours? Keep a notebook in the case and jot down the date and how long it ran each time. It does the same job, and your mechanic will thank you for it.
Camping and Worksite Use
Camping and trade use burn through hours much faster. Here's how long 2,000 hours lasts at different rates.
| Use | Hours a year | Years to reach 2,000 hours |
|---|---|---|
| Home backup, monthly run plus a few blackouts | 40 | 50 |
| Camping, three weeks a year at 8 hours a day | 168 | About 12 |
| Weekend worksite, one day a week at 8 hours | 416 | About 5 |
| Full-time worksite, 8 hours a day for 230 days | 1,840 | About 1 |
If a petrol portable is on site every day, it's a consumable. Westinghouse cuts its warranty to one year or 500 hours for commercial use, and any buyer with an ABN counts as commercial.
What Shortens a Generator's Life
Most generators don't die of old age. They die of the same few habits.
Stale Fuel and Poor Storage
The Westinghouse iGen2250 manual says the most commonly experienced faults with portable generators come down to contaminated or stale fuel, and fuel can go bad in as little as 30 days.
That's why a backup generator with 50 hours on it can be dead in the shed. See how long a generator can sit unused and where to keep a generator when it's not in use.
Skipped Oil Changes
Westinghouse's maintenance schedule has the first oil change after 20 hours or the first month, then every 100 hours or six months, with valve clearances checked by a dealer at 500 hours or two years. Honda's GX engine schedule lands on the same 20 and 100-hour marks.
The oil change guide has the detail, and winterising a generator covers the off-season.
Running It Too Hard
Queensland's Electrical Safety Office says a generator shouldn't run continuously above 80 per cent of its rated capacity. A machine that's always near flat out is working harder every hour it runs.
Motor starts add to the strain. The same page says appliances with motors, like fridges and freezers, can use up to ten times their listed wattage when starting up.
If yours is always straining, it's probably too small. The generator size guide works it out.
So how long do home generators last? Think 1,000 to 2,000 hours for petrol and a lot more for a serviced diesel. For backup at home that's often decades, as long as the fuel and the oil are looked after.
Buying one to last? The generator finder matches a generator to how you'll use it, or ring us on 03 7056 6732, or SMS 0476 330 590.
