The Main Components of a Diesel Generator

Since the invention of the diesel engine, it has become the predominant source of power for heavy machinery, railroad locomotives, and more. There are many uses for the diesel engine, but none are like the diesel generator. A diesel generator is a combination of a diesel engine and an electric generator that work together to generate electricity. Many industries rely on this machine to supply electricity in remote locations and provide backup power to structures reliant on power, such as hospitals and communication towers. To understand how a diesel generator works, it is important to understand its main components. 

Fuel System

The purpose of the fuel system is to store and supply fuel to the engine. This starts the mechanical process and consists of a tank with fuel lines connected to the engine. The size of the fuel tank determines how long the generator can run.

Diesel Engine

The diesel engine is the source of power for the generator to operate. The chemical energy in diesel is converted into mechanical energy that starts the operation of the machine. Because the engine is the source of mechanical energy, the size of the engine matters. The larger the engine, the greater the power.


While the engine provides mechanical energy, it does not generate electricity. The alternator is responsible for converting the mechanical energy from the engine into electrical energy that generates the power output.

DEF System

The DEF storage and supply system monitors and injects DEF into the exhaust stream to break down dangerous emissions produced by diesel. This reduces emissions and makes sure the generator meets emission standards.

Cooling System

The cooling system prevents the generator from overheating by removing excess heat from the engine.

Diesel generators are one of the many pieces of equipment we refuel at PSPI. Whether your generator is providing backup power to your warehouse or keeping your lights on at a remote construction project, PSPI delivers diesel to all jobsites throughout California. Give us a call at (800) 679-1700 or send us an email and we can help keep your job running 24/7/365.