The single-phase petrol generator type of generator is generally used as a standby generator, or as a fail over for when the main power supply fails. It is also often used for supplying temporary electrical power to construction sites. It can also be attached to a power tool for where power becomes difficult to route from the main power supply.

Single-phase petrol generators are powered by petrol fuel. They produce a single, constant wave of power which varies according to the speed at which the petrol engine can produce the electricity.This does not necessarily mean that the appliances will experience a drop in power. In fact, many household appliances are designed to operate on single-phase power supply. This kind of generator is more cost effective than a three-phase system generally. They are  a better choice for residential or industrial applications, or where the demand for power is relatively low.