- 1 How does a generator work?
How does a generator work?
Electric generator definition
An electric generator is a device that converts mechanical energy obtained from an external source into electrical energy as the output.
How does a generator work?
It is important to understand that a generator does not actually ‘create’ electrical energy. Instead, it uses the mechanical energy supplied to it to force the movement of electric charges present in the wire of its windings through an external electric circuit. This flow of electric charges constitutes the output electric current supplied by the generator. This mechanism can be understood by considering the generator to be analogous to a water pump, which causes the flow of water but does not actually ‘create’ the water flowing through it.
The modern-day generator works on the principle of electromagnetic induction discovered by Michael Faraday in 1831-32. Faraday discovered that the above flow of electric charges could be induced by moving an electrical conductor, such as a wire that contains electric charges, in a magnetic field. This movement creates a voltage difference between the two ends of the wire or electrical conductor, which in turn causes the electric charges to flow, thus generating electric current.
Main components of a generator
The main components of an electric generator are as follows :
(3) Fuel System
(4) Voltage Regulator
(5) Cooling and Exhaust Systems
(6) Lubrication System
(7) Battery Charger
(8) Control Panel
(9) Main Assembly / Frame
Types of Generators
Diesel engines are noted for durability, long-life and normally lower maintenance. A diesel engine operating at 1800 rpm can run from 12,000 to 30,000 hours between major maintenance services. The same gas powered engine may need major servicing after 6,000 to 10,000 hours of operation.
Diesel fuel burns cooler than gasoline reducing the heat, and the wear, on the engine. Power produced from diesel generators can also be lower in cost through the increased efficiency, higher energy density, of diesel fuel. While diesel was formally a “dirty” fuel, improvements in engine technology have reduced diesel emissions. Blends of up to 20% biodiesel can normally be used safely in regular diesel engines.
Natural Gas Generators
Natural gas generators use propane or liquefied petroleum gas. Natural gas offers the advantage of easy storage in below or above ground tanks. It is also a clean burning fuel, reducing problems with emissions. Generators that run on natural gas are durable but they can be more expensive in initial purchase.
While natural gas is often less expensive than other fuels, it must be trucked to your facility, which can increase the operating costs. A natural gas generator has a lower output than a similar sized diesel generator. You may need to move up a size to get the same results. Natural gas generators are an excellent choice for technology providers as a backup power source.
Gasoline powered generators usually have a lower purchase price. While gas generators can run for long periods, they do require maintenance that is more extensive. The gasoline deteriorates rubber components causing the engine to wear faster. Gasoline storage is more difficult due to a higher potential for fire or explosion. In addition, the gasoline itself deteriorates making long-term storage a less than ideal choice. Gasoline generators are not the best choice for larger industrial applications.
Portable Industrial Generators
Portable industrial generators are trailer-mounted versions, not the type that you can simply pull behind you as you walk. Large portable generators make an excellent choice for use on construction sites before an electrical supply is established. These are also frequently used by emergency responders when a large amount of power is needed on location.
Commercial or industrial grade marine generators are designed to withstand rugged environmental conditions. Caterpillar, Kohler and Cummins are three of the manufacturers that build marine specific generators. This type of generator is required for use near salt water and recommended for large vessels or oil rigs. While marine generators are available as gas or diesel powered, diesel is the choice for industrial use.
Heavy Fuel Oil Generators
Heavy fuel oil generators offer significant fuel savings over the cost of diesel fuel. The overall generator size can often be smaller due to the use of a small higher speed engine. Wartsila is one manufacturer of heavy fuel oil generators. This fuel comes under the category of number 5 or 6 fuel oil and the availability of heavy fuel oil must be considered when selecting this type of generator.