How Does a Generator Work and How to Operate a Generator


Generators are helpful devices that help generate power during a power blackout and prevent disruption of daily activities in our homes, offices and industries. Generators are available in various physical designs and different electrical voltage output for use in various applications.

In the following article, we will take a look at how a generator operates, the main parts of a generator, and how a generator works as a free electricity source in industrial and residential applications.

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How does a generator work?

First of all, an electric generator is a device designed to change mechanical energy sourced from an external source into electrical energy as the main output.

It is paramount to note that a generator doesn't make electrical energy. Rather, it utilizes the mechanical energy provided to it to facilitate the development of electric charges available in its wire winding through an external electric circuit.

This progression of electrical charges comprises the output electric charges provided by the generator. The generator working mechanism can be exactly likened to a water pump that causes water to flow, but itself does not create the water running through it.

The latest generation of generators works on the principle that was discovered by Michael Faraday in 1832. That is the principle of electromagnetic induction. Faraday found out that flow of charges can be prompted by simply moving a good electrical conductor like a wire with charges in a field with magnetic charges.

This development makes a voltage difference between the two finishes of the wire or electrical channel, which thus makes the electric charges stream, in this way producing electric flow.

Primary Parts of a Generator

The first parts of a generator that produces electric energy can be roughly categorized as follows:

  • The engine
  • Fuel System
  • Voltage Regulator
  • Alternator
  • Exhaust and cooling mechanism
  • Lubricating System
  • Battery Charger
  • Regulating Panel
  • The frame or primary assembly
  • An in-depth description of the basic constituents of an electric generator is as follows.

    The Generator Engine

    Generator engine

    The source of the mechanical energy intake of the generator is the engine. Therefore the maximum power output supplied by the generator is directly proportional to the size of the engine. The following factors should be considered while checking your generator engine.

    First, consult your engine manufacturer to get all specific engine operations and maintenance schedules like;

    (a)Type of fuel

    Generator engines work with different types of fuel, for instance, diesel, natural gas, propane (both in gas and liquid form) or gasoline. Depending on sizes, large engines operate on natural gas, diesel and both liquid and propane gas while small ones on gasoline. Though other engines are bi-fuel operation meaning they can operate on dual feed.

    1. (b) Overhead Valve (OHV) Engines versus non-OHV Engines – OHV engines differ from other engines in that the intake and exhaust valves of the engine are located in the engine's head cylinder rather than being attached on the block of the engine. OHV usually has many benefits when compared to other engines. The benefits include:
  • Compact design
  • Simpler operation mechanism
  • Durability
  • User-friendly in operations
  • Low noise during operations
  • Low emission levels
  • (c) Cast iron sleeve (CIS)

    The cast iron sleeve is a covering in the inner part of the engine cylinder. It helps in reducing friction, making it last longer. Often, OHV engines have CIS therefore always check for this property in the engine generator. However, CIS is not that costly but very crucial in keeping the engine durable for a long time.


    The alternator, commonly referred to as gen head, is a constitute of the generator that creates the electrical energy output from a mechanical input provided by the motor or engine.

    The alternator comprises of moving parts and stationery both covered in housing. The parts work in unison to prompt relative movement on both the electric and magnetic fields, which thus produces power.

    Fuel System

    The fuel tank typically has adequate ability to keep the generator functioning for about five to six hours averagely. Small generator units, for instance, have the fuel tank mounted at the top frame of the generator or the fuel tank is part of the skid base of the generator.

    For business uses, it might be important to raise and introduce an external fuel tank system. However, external fuel tank installation should be done by a specialist and according to the city planning regulations.

    Voltage Regulator

    As the name suggests, this generator part controls the voltage output of the generator.

    Alternating Current Voltage

    This cycle goes on until the generator starts to deliver voltage output that is proportional to the generator's full working limit. As the yield of the generator builds, the voltage controller delivers less DC.

    The voltage regulator produces more Direct Current as the generator's output increases. The voltage controller will only attain a state of equilibrium once the generator has reached its full operating capacity.

    The generator's voltage output will dip a little when you add a load to it. When this happens, the generator's regulator will be prompted immediately, and the cycle above begins. As always the cycle will go on up to when the output of the generator reaches its full capacity of operation.

    Exhaust and cooling System

    Cooling System

    When the generator is continuously used, most of its components get heated up. That is why it's important to have a ventilation and cooling mechanism to cool the generator when it's heated up.

    Fresh or rather raw water is usually utilized as a coolant for generators small generators, and big generators of up to 2250kW and above that are utilized for commercial purposes. For stator windings of large generator units, hydrogen is preferred because it is more effective in heat absorption when compared to other coolants.

    Hydrogen expels heat from the interior of the generator and moves via a heater exchange to another cooling system that has de-mineralized water which functions as a coolant. This is the reason as to why huge generators and little force plants normally have huge cooling towers close to them.

    Most of the other basic applications such as industrial and residential have a fan, and a standard radiator mounted on them and worked as the main cooling mechanism.

    Exhaust System

    Fumes produced by a generator are much the same as fumes from some other gasoline or diesel motor and contain exceptionally poisonous synthetic substances that should be appropriately managed. Therefore, it is basic to introduce a sufficient fume disposal system to dispose of the gases emitted.

    This point cannot be underrated as carbon monoxide poisoning remains among the leading cause of deaths, especially in places affected by a hurricane because people despise carbon monoxide dangers until it is late.

    Lubricating System

    A generator requires lubrication because its engine comprises moving parts. Lubrication ensures the smooth operation of a generator for a long time and durability. The oil is stored in a pump; it is from the pump that the generator's engine is lubricated.

    It is recommended that you inspect the level of the lubricant after every 8 hours of continuous operation. Also, check if the lubricant is leaking and replace the lubricant after 500 hours of operation.

    Battery Charger

    The battery of a generator operates the start function. The generator battery is kept charged by the battery charger that supplies it with precise voltage 'float'.

    The battery normally remains undercharged if the float voltage is very low and on the other side of the float is too high the lifespan of battery shortens.

    To prevent corrosion, battery chargers are usually made of stainless steel. They are additionally entirely programmed and don't require any setting to be changed or adjusted. The battery charger's direct current output is usually set at around 2.33 volts for every cell.

    For lead-acid batteries, this is the precise float voltage. The battery charger has a secluded direct current voltage yield that does not alter with the generator's normal functioning.

    Control Panel

    This is the UI of the generator and contains arrangements for electrical controls and outlets. Various makers have different highlights to provide in the regulator panels of their units.

    Main Assembly/Frame

    Almost all generators, stationary or portable, have redone casings that offer auxiliary base support. The casing likewise enables the charges to be easily earthed for safety purposes.


    How Does a Random Number Generator Work?

    Random number generators gather entropy to generate random numbers or random data from the physical world surrounding them. The generators use seed value and an algorithm for random numbers that do not need to be random.

    How Does a Van De Graaff Generator Work?

    A Van de Graaff generator utilizes a moving belt and static electricity to create charges on a huge spherical metal to a very high voltage. When the belt moves, electrons also migrate to the silicon roller from the runner belt. This causes the belt to be negatively charged while the roller is negatively charged.

    How Does a Generator Transfer Switch Work?

    When the generator is running at the right speed, its automated transfer button securely closes off the utility line and at the same time opens the generator power line from the generator.

    In no time, your generator framework starts providing power to the basic emergency circuits of your business or residential area.

    How Does a Home Generator Work?

    A home standby generator is an emergency electrical mechanism that works automatically. Immediately the power goes off an automated transfer button senses the power outage and prompts the generator to switch on and then an electrical load is transferred to the generator. From there the standby generator will start to supply electricity to the circuits.

    How Does a Generator Work for Your House?

    Portable generators produce power by running a gas-fueled motor that turns an on-board alternator to create power. Electrical plugs on the unit permit you to plug additional lines, electric-fueled apparatuses and machines into it. Ordinarily, the more watts equal to the more things you can control up.


    Throughout the years, generators have demonstrated themselves to be commendable devices for some homeowners and entrepreneurs around the world, giving an important reinforcement when a power outage is experienced in an area. Otherwise, without them, a lot of inconveniences would have been experienced.

    Having a generator does not necessarily imply paying for it and trusting it works when the electricity isn't available. If at all you are genuinely thinking about going down the course of purchasing another generator, it's a savvy thought to figure out how it functions and understanding how it fills the void of intensity, during a force cut or when there is no force close by.