Generators can be classified in one of three ways depending on their functionality. A diesel generator is the combination of a diesel engine with an electric generator (Often an alternator) to generate electrical energy. This is a specific case of engine-generator. Diesel generating sets are used in places without connection to a power grid, or as an emergency power-supply if the grid fails, as well as for more complex applications.

Continuous and prime power generators are very similar as they would function as the main source of power and are designed to operate continuously for longer periods of time. The main difference between the two is that continuous generators are designed to operate continually with a consistent load of power; prime generators are designed to operate for long duration’s but at variable loads.

Standby generators are designed mainly to run only when there is an outage or shortage to the main power source and/or in back up situations. This gives a standby generator two advantages over continuously operated power generators.

  • Standby units have time to naturally cool down when not in operation
  • You are able to carry out maintenance without disrupting the power supply.

Where there is no access to the main power grid or electric power supply, continuous and prime generators are primarily used. This is usually in remote locations such as oil/ gas operations, construction, ships and mining areas.


Continuous power generators usually operate at a lower revolution speed. Normally, diesel generator sets operate at 1800 ( RPM) where continuous power generators of larger capacities have been designed to operate at 1200 ( RPM) or 900 (RPM). This increasing the lifespan of the unit significantly and reducing maintenance costs.


Continuously operated generators usually provide 25% to 100% of the rated capacity for a long duration of time, this unit usually providing most of the rated capacity constantly. In such cases where a diesel generator is the main supply of power, it is ideal and advised that there are two identical generators installed.


It is very important to understand the purpose of your generator and what you need from it. In some cases a generator is only needed for standby power. From standby generators to larger prime and continuous generators.