How does a diesel generator work?

In simplified form, how does a diesel generator work?

  1. First, air is propelled into the generator until it is compressed;
  2. Subsequently, diesel is injected;
  3. The combination of these two processes, the compression of the air and the subsequent injection of the fuel, will contribute to generate the (intense) heat that triggers the fuel to ignite.
  4. The combustion of the diesel starts the generator, making the central shaft move, and transforming the mechanical energy into electrical power, with the help of the alternator;
  5. Thus, the generator starts producing the necessary electrical energy to be distributed according to the needs of the equipment connected to it or the place/space it will supply.


The diesel generator is an equipment whose use is indicated for applications that require greater power and/or continuous operation, since this fuel is burned at a higher temperature, compared to other types, such as gasoline, and therefore is more efficient and ensures greater power to the generator.

It should be noted that diesel generators can be used for quite a long time, being run for hours, weeks, or simply until the main power comes back on. To do so, you must make sure that it is properly fueled so that it can fulfill its function. Since this type of generator is in operation for longer periods, it necessarily involves regular maintenance so that you can check that all the components are in full working order. It is important to pay special attention to the generator's engine, to maintain it and lubricate it because it will run uninterruptedly for hours on end, and it will need this care to maintain its efficiency.

Diesel generators have the advantage of being more economical and are indicated for cases in which the main premise is to ensure fault-free power supply and high efficiency for high power, as is the case of large industries, for example. On the other hand, diesel is also an interesting option because it is a fuel that ensures better performance, which is extremely important in cases where efficiency is a requirement.

Before purchasing a generator, you must take some factors into consideration, find out which ones.


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