Guide · Generators

Inverter or conventional generator

An inverter generator delivers stable voltage with a pure sine wave, is lighter and usually quieter, so it is better for computers, gas boilers and other sensitive electronics. A conventional generator gives more kW for the same money and has a larger tank, so it is better for tools, pumps and long running when electronics are not involved.

Inverter: pure sine wave, Eco mode, lower weight
Conventional: lower price per kW, larger tank
Prices in the guide: October 2026

How they work

A conventional generator has an engine that turns the alternator at a constant speed, because the 50 Hz frequency depends on the speed. The voltage is regulated by the AVR (automatic voltage regulator). The engine runs at the same speed even when the load is small.

An inverter generator converts the current from the alternator electronically: first to direct current, then back to alternating current at 230 V, 50 Hz. So the frequency does not depend on engine speed, and the voltage is stable and a pure sine wave.

Pure sine wave and sensitive electronics

Computers, televisions, chargers, gas boiler control boards and inverter air conditioners work with built-in electronics. These cope best with stable voltage without distortion.

An inverter is the safer choice when you are powering a computer, a boiler or medical equipment at home.
A conventional generator with an AVR works well with tools, heaters, lighting and pumps.
If the device manufacturer requires a certain voltage quality, it says so in the device instructions.

Noise and Eco mode

Eco mode on an inverter reduces the engine speed when the load is low. The generator is then quieter and uses less fuel. A conventional generator does not have this option; the engine runs at full speed regardless of consumption.

An inverter is not always quieter. Small inverters in a closed enclosure, such as the KSB 22i S (62 dB), are quieter than most conventional ones, but the KSB 21i is rated 70 dB, the same as the conventional KS 7000E. Look at the figure for the specific model.

The manufacturer states noise as two values (e.g. 62/87 dB). The lower is the sound pressure level at a distance from the generator, the higher is the sound power level. In this guide we give the lower one.

Parallel operation

Some inverters have parallel operation: you connect two generators with a parallel kit and get a higher total output on a single outlet. The advantage is that two smaller generators are easier to carry than one large one, and when you need only a little power, you start just one.

Parallel operation is in the specification of, for example, the KSB 12i S, KS 2100iG S, KS 3100i S and KS 5500iE S ATSR. Which models you may connect, and with which accessories, is stated in the manufacturer's instructions.

The conventional generators in our range do not have parallel operation in their specifications.

Comparison on models from our range

Prices are valid at the time of writing (October 2026). The price per kW is calculated on the rated output.

Model	Type	Output	Weight	Noise	Tank, run time	Price	Per kW
KSB 2800A	conventional	2.8/2.5 kW	36.2 kg	71 dB	12 l	€431.25	about €173
KS 3000E	conventional, electric start	3.0/2.6 kW	46.1 kg	68 dB	15 l, about 15 h	€618.75	about €238
KSB 21i	inverter	2.0/1.8 kW	21 kg	70 dB	10 l, about 13 h	€485	about €269
KS 3100i S	inverter	3.1/2.8 kW	21.5 kg	63 dB	4 l, about 2.7 h	€882.50	about €315
KS 7000E	conventional, electric start	5.5/5.0 kW	76.2 kg	70 dB	25 l, about 17 h	€1,031.25	about €206
KS 5500iE S ATSR	inverter, ATS output	5.5/5.0 kW	52 kg	66 dB	13.5 l, about 8.4 h	€1,650	about €330

The run time is at 50% load, per the manufacturer's specification. For the KSB 2800A the run time is not stated.

What the comparison shows

Price: for the same output the conventional one is cheaper. At 5 kW the difference between the KS 7000E and the KS 5500iE S ATSR is about €620.
Weight: the inverter is lighter. The KS 3100i S weighs 21.5 kg with a higher output than the KS 3000E, which weighs 46.1 kg.
Run time: conventional models have larger tanks and run longer without refuelling.
Voltage quality: an advantage of the inverter, important for electronics.

When to choose which

Use	Recommendation
Camping, boat, holiday home, carrying in a car	small inverter
Backup for a house with a boiler and a computer	inverter, with ATS if needed
Building site, tools, pumps	conventional
Long running without refuelling	conventional with a large tank, or diesel
Three-phase loads	conventional three-phase or a 1/3 model

To check how much power you need, use the power calculator.

Frequently asked questions

Can I connect a computer to a conventional generator?

For computers, televisions and boilers an inverter is safer because it delivers stable voltage with a pure sine wave. A conventional generator with an AVR is better kept for tools, heaters and pumps.

Is an inverter generator always quieter?

Not always. Small inverters in an enclosure usually are, but noise should be compared using the figure for the specific model, for example 62 dB for the KSB 22i S and 70 dB for the KSB 21i.

What is Eco mode on a generator?

Eco mode reduces the engine speed when the load is low, so the generator uses less fuel and runs more quietly. Inverters have it; conventional generators do not.

Can I connect two generators to get more power?

Only if both models have parallel operation and you connect them with the accessories specified by the manufacturer. Ordinary conventional generators must not be connected in parallel.

Why is an inverter more expensive per kW?

An inverter has the electronics for converting the current, and often a lighter enclosure and a smaller engine. In our range an inverter costs about €270 to €330 per kW of rated output, and a conventional generator about €170 to €240, based on October 2026 prices.