DIESEL FUELED GENERATORS - A RECOMMENDATION

Diesel engine generators the best choice for your generator needs for longevity & efficiency.
Why is diesel a better choice for your generator application?

We recommend diesels due to their:

a) Longevity - Think of all the18 wheeler trucks capable of 1,000,000 miles of operation before major service. Most trucks are diesel powered.

b) Lower fuel costs - Diesel uses less fuel consumption per kilowatt (kW) produced).

c) Lower maintenance costs - diesel have fewer parts. no spark system, more rugged and more reliable engine.

Today’s modern diesels are quiet and normally require less maintenance than comparably sized gas (natural gas or propane) units. Overall operating costs are typically thirty to fifty percent less than gasoline units.

Diesel engines running at 1800 RPM and water cooled operate on average for 12,000 to 30,000 hours before major maintenance is required. Gasoline engines running at 1800 RPM and water cooled gas units normally operate on average for 6,000 to10,000 hours because they are built using lighter duty gasoline engine blocks.

Gasoline engines running at 3600 rpm and air cooled are normally replaced – not overhauled at 500 to 1500 hours.

Gasoline units run hotter due to the higher BTU rating of the fuel, you will therefore see significantly shorter gasoline engine life. Diesels run cooler and last longer.

DIFFERENCES BETWEEN GASOLINE AND DIESEL ENGINES

Fuel Gasoline Diesel

Fuel
Ignition

Gasoline
Takes a mixture of gas and air, compresses it and ignites the mixture with a spark.

Diesel
Takes in just air, compresses it and then injects fuel into the compressed air. The heat of the compressed air lights the fuel spontaneously.

Fuel
Compression

Gasoline
Compresses at a ratio of 8:1 to 12:1

Diesel
Compresses at a ratio of 14:1 to as high as 25:1. The higher compression ratio of the diesel engine leads to better efficiency.

Fuel
Fuel Provision

Gasoline
Uses either carburetion, in which the air and fuel is mixed long before the air enters the cylinder, or port fuel injection, in which the fuel is injected just prior to the intake stroke (outside the cylinder).

Diesel
Uses direct fuel injection -- the diesel fuel is injected directly into the cylinder. The diesel engine has no spark plug, that it intakes air and compresses it and that it then injects the fuel directly into the combustion chamber (direct injection). It is the heat of the compressed air that lights the fuel in a diesel engine.

Fuel
Injection Process

Gasoline
Most car engines use port injection or a carburetor rather than direct injection. In a car engine, therefore, all of the fuel is loaded into the cylinder during the intake stroke and then compressed. The compression of the fuel/air mixture limits the compression ratio of the engine -- if it compresses the air too much, the fuel/air mixture spontaneously ignites and causes knocking.

Diesel
Diesels compress only air, so the compression ratio can be much higher. The higher the compression ratio, the more power is generated.

Fuel
Injector Engineering


Gasoline
Fuel injected gasoline engines is more refined and less problematic then diesel engines because the fuel is easier to ignite.

Diesel
The injector on a diesel engine is its most complex component and has been the subject of a great deal of experimentation -- in any particular engine it may be located in a variety of places. The injector has to be able to withstand the temperature and pressure inside the cylinder and still deliver the fuel in a fine mist. Getting the mist circulated in the cylinder so that it is evenly distributed is also a problem, so some diesel engines employ special induction valves, pre-combustion chambers or other devices to swirl the air in the combustion chamber or otherwise improve the ignition and combustion process.

Fuel
Starting Process

Gasoline
Smaller engines and engines that do not have such advanced computer controls use glow plugs to solve the cold-starting problem

Diesel
When a diesel engine is cold, the compression process may not raise the air to a high enough temperature to ignite the fuel. The glow plug is an electrically heated wire (think of the hot wires you see in a toaster) that helps ignite the fuel when the engine is cold so that the engine can start.
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In today's world, where fuel prices are increasing as a consequence of spiraling demand and diminishing supply, you need to choose a cost effective fuel to meet your needs. Thanks to the invention of Rudolph Diesel, the diesel engine has proved to be extremely efficient and cost effective. Diesel fuel is priced moderately higher than gasoline but diesel has a higher energy density, i.e. more energy can be extracted from diesel as compared with the same volume of gasoline. Diesel engines in automobiles provide higher mileage, making it an obvious choice for heavy-duty transportation and equipment. Diesel is heavier and oilier compared with gasoline, and has a boiling point higher than that of water. Diesel engines are attracting greater attention due to higher efficiency and cost effectiveness.

How Does a Diesel Engine Work?

The distinction lies in the type of ignition. While gasoline engines operate on spark ignition, diesel engines employ compression - ignition for igniting the fuel. In the latter, air is drawn into the engine and subjected to high compression that heats it up. This results in a very high temperature in the engine, much higher than the temperature attained in a gasoline engine. At peak temperature and pressure, diesel that is let into the engine ignites on account of the extreme temperature.

In a diesel engine air and the fuel are infused into the engine at different stages, as opposed to a gas engine where a mixture of air and gas are introduced. Fuel is injected into the diesel engine using an injector whereas in a gasoline engine, a carburetor is used for this purpose. In a gasoline engine, fuel and air are sent into the engine together, and then compressed. The air and fuel mixture limits fuel compression, and hence the overall efficiency. A diesel engine compresses only air, and the ratio can be much higher. A diesel engine compresses at the ratio of 14:1 up to 25:1, whereas in a gasoline engine the compression ratio is between 8:1 and 12:1. After combustion, the combustion by-products are removed from the engine through the exhaust. For starting during cold months extra heat is provided through 'glow plugs'.

Diesel engines can either be two cycle or four cycle and are chosen depending on mode of operation. Air-cooled and liquid-cooled engines are the variants to be chosen appropriately. It is preferable to use a liquid-cooled generator as it is quiet in operation and has evenly controlled temperature.

Advantages of a Diesel Engine

The diesel engine is much more efficient and preferable as compared with gasoline engine due to the following reasons:

Modern diesel engines have overcome disadvantages of earlier models of higher noise and maintenance costs. They are now quiet and require less maintenance as compared with gas engines of similar size.
They are more rugged and reliable.
There is no sparking as the fuel auto-ignites. The absence of spark plugs or spark wires lowers maintenance costs.
Fuel cost per Kilo Watt (kW) produced is thirty to fifty percent lower than that of gas engines.
An 1800 rpm water cooled diesel unit operates for 12,000 to 30,000 hours before any major maintenance is necessary. An 1800 rpm water cooled gasoline unit usually operates for 6000-10,000 hours before it needs servicing.
Gas units burn hotter than diesel units, and hence they have a significantly shorter life compared with diesel units.

Applications & Uses for Diesel Engines

Diesel engines are commonly used as mechanical engines, power generators and in mobile drives. They find wide spread use in locomotives, construction equipment, automobiles, and countless industrial applications. Their realm extends to almost all industries and can be observed on a daily basis if you were to look under the hood of everything you pass by. Industrial diesel engines and diesel powered generators have construction, marine, mining, hospital, forestry, telecommunications, underground, and agricultural applications, just to name a few. Power generation for prime or standby backup power is the major application of today's diesel generators. Check out our article on the various types of engines and generators and their common applications for more examples.

Power Generators

Diesel powered generators, or electrical generator sets, are used in countless industrial and commercial establishments. The generators can be used for small loads, such as in homes, as well as for larger loads like industrial plants, hospitals, and commercial buildings. They can either be prime power sources or standby/back-up power sources. They are available in various specifications and sizes. Diesel generator sets rating 5-30KW are typically used in simple home and personal applications like recreational vehicles. Industrial applications cover a wider spectrum of power ratings (from 30 kW to 6 Megawatts) and are used in numerous industries throughout the globe. For home use, single-phase power generators are sufficient. Three-phase power generators are primarily used for industrial purposes.