Short answer: an inverter generator converts its power electronically, producing clean, stable electricity that is safe for TVs, laptops, routers and refrigerators with electronic controls. It also changes engine speed to match the load, so it is usually quieter and uses less fuel at low load. A conventional generator runs at a fixed speed and is cheaper per kilowatt, which makes it great for tools, lights and heavy loads.
How they work
A conventional generator’s engine spins at a fixed speed (about 3000rpm for 50Hz electricity) whatever you plug in. An inverter generator produces power, converts it to DC and then back to a clean 50Hz AC wave, so the engine can slow down when you need less power. You can see this in our own range: the TOTAL 3.8kW inverter generator varies its speed between 3300 and 4800rpm, while TOTAL conventional models run at a fixed 3000rpm.
Comparison
| Inverter generator | Conventional generator | |
|---|---|---|
| Power quality | Clean and stable, safe for sensitive electronics | Fine for tools, lights and motors |
| Engine speed | Varies with the load | Fixed |
| Noise | Usually quieter, especially at low load | Louder (except enclosed silent diesel models) |
| Fuel use at low load | Lower | Higher |
| Price per kW | Higher | Lower |
| Best for | Homes, shops, electronics, camping | Construction sites, workshops, heavy loads |
How to size a generator
- List what you need to run at the same time and add up their watts (check the label on each appliance).
- Add extra for motors. Fridges, pumps and air conditioners draw much more power for a moment when they start, often two to three times their running watts.
- Look at rated output, not max output. Rated output is what the generator can supply continuously.
- Keep a margin of around 20% so the generator isn’t running at its limit.
| Need | Suggested size (rated output) |
|---|---|
| Lights, router, phone charging, TV | Under 1kW |
| Basic home backup (fridge, lights, TV, router) | About 2.5–4kW |
| Larger home or small shop, including a water pump | About 6–8kW |
| Workshop or whole-house with heavy appliances | 8–10kW and above |
Our generator picks
Inverter generators for homes, shops and electronics: 3.8kW rated with 8.5 hours runtime at 50% load, or 8.2kW rated with remote start for bigger needs.
Inverter Gasoline Generator 8.5h - TOTALView product →
Inverter Gasoline Generator - TOTALView product →
Conventional petrol generators: from a compact 0.65kW unit for lights and charging, to 2.8kW and 10kW models with electric start.
Gasoline Generator - TOTALView product →
Gasoline Generator with Battery - TOTALView product →
Gasoline Generator T.C.I - TOTALView product →
Silent diesel generators: enclosed, heavy-duty units for long running hours, with automatic transfer switch (ATS) options.
See the full range in Generators.
Safety first
- Never run a generator indoors, in a garage or near windows. Exhaust gas (carbon monoxide) is deadly.
- Connecting a generator to your home wiring should be done by a qualified electrician using a transfer switch.
- Refuel only when the engine is off and cool.
Frequently asked questions
Can I run a refrigerator on a conventional generator?
Yes, as long as the generator’s rated output covers the fridge’s starting surge. For modern fridges with electronic controls, an inverter generator is the safer choice.
Are inverter generators quieter?
Generally yes, because the engine slows down at low load. Enclosed silent diesel generators are also designed for low noise.
What is ATS on a generator?
An automatic transfer switch (ATS) starts the generator and switches your supply over automatically when the mains power cuts out, then switches back when it returns.
Petrol or diesel generator?
Petrol generators are lighter and cheaper to buy. Diesel generators cost more but are built for long running hours and are common for shops and buildings.
