What can be powered by an electricity generator?

Electricity generators can be used not only as the main source of energy in places where the electricity grid is not available,but they are also often used as a backup source for houses and cottages in case of calamity. Electric generators are also suitable for use in caravans, boats and other mobile devices.

As you know, selecting the correct generator output is not a simple matter, as it is not possible to determine the output of a generator simply by looking at the input power listed on the label of the equipment being connected, or, by simply adding up the data listed on the labels of all the appliances being connected. The main problem is that many appliances require several times the power input indicated on the label to start up. However, this start-up current required for the appliance to start up is usually not indicated on the label.

Usually simple appliances with the resistive principle can be connected to the generator without any problems. These include incandescent bulbs, but also most of the various heaters, cookers, hair dryers, irons, etc., which power input is usually constant and therefore the power input stated on the label can be easily used for comparison with the generator power.

Electric motors is the most common problem with determining the correct input power for appliances with induction. Unfortunately, this includes the vast majority of power tools, pumps, electric saws, refrigerators, washing machines and lawnmowers. For these appliances it is recommended that the generator has at least 10%, better still 30% reserve of continuous power compared to the stated power input of the appliance, but an additional reserve is necessary for starting the motor. It is always better to be guided by the starting current specified by the appliance manufacturer, but if this figure cannot be found, it is generally agreed that the generator output must be up to 3 times higher to start a synchronous motor up to about 1.5 kW; for motors above 1.5 kW, the required generator output may be more than 5 times higher. The required starting power is often up to 10 times higher than the power input stated on the label for compressor fridges and freezers. For the power supply of sensitive electronics, computers, modern televisions and the like, it is necessary to take into account the regulation of the generator output voltage. This regulation ensures the stability of the output voltage and frequency.

The simplest power generators are usually equipped with a capacitive regulation, which is sufficient to drive most hand tools, lighting, pumps, etc. But because of that the regulation is not able to react quickly and the output voltage can fluctuate in the range of several tens of volts. The advantage of these generators is that they are better able to withstand various current surges, but they cannot be used to power sensitive electronics.

The more expensive and sophisticated generators are equipped with AVR electronic control, which ensures relatively stable output voltage and frequency with a characteristic that is similar to the characteristic in a normal power grid. The output characteristic is also dependent on the speed of the motor, which may change suddenly for various reasons. It is therefore advisable to use a UPS with suitable protection for the connection of the computer, similarly to the connection to the normal mains. It is better to consult the manufacturer or electronics dealer before connecting sensitive electronics.

Inverter generators have the best output characteristics. The measured output voltage and frequency usually achieves a better characteristic than the conventional power grid. This makes them suitable for powering sensitive electronics. The output is not affected by the speed of the motor and the output voltage and frequency is generated by the inverter. The speed of the motor can therefore be varied according to the actual power demand, which is why modern inverter power plants have a significantly lower fuel consumption than capacitive or AVR controlled power plants.