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Diesel fuel is derived from crude oil. It is a mixture of hydrogen and carbon
molecules. It is developed for engines that provide energy for power, flow readily
in cold temperature, provide low emission, provide good fuel economy, and allow
easy start-up. Power generators are run by diesel fuel. The fuel also runs diesel-powered
vehicles, such as ships, buses, or trucks. Diesel engines of these types of
vehicles are internal combustion engines.
Diesel is used in a high-compression engine. Air is compressed until it is
heated above the autoignition temperature of diesel. Then the fuel is injected
as a high pressure spray. There is no ignition source. As a result, diesel is
required to have a high flash point and a low autoignition temperature. The
flashpoint of a fuel is the lowest temperature at which it can form an ignitable
mix with air. The high flash point in diesel fuel means that it does not burn
as easily as gasoline, which is a safety factor. Too low of a flash point is
a fire hazard because ignition may continue and lead to explosion.
Autoignition temperature is the temperature at which a substance can be brought
to flames without any sort of external force, such as a flame or spark. There
are three different types of diesel fuel. These are Diesel No. 1, Diesel No. 2,
and Diesel No. 4. The ignition temperature of Diesel fuel No.1 ranges from 450
to 602 Kelvin, Diesel fuel No. 2 ranges from 527 to 558 Kelvin,
and Diesel fuel No .4 is 536 Kelvin. | Physiochemical properties of diesel fuel |
| Property |
Diesel Fuel (general) |
Diesel Fuel No. 1 |
Diesel Fuel No. 2 |
Diesel Fuel No. 4 |
| Autoignition Temperature (°C) |
|
177-329 |
254-285 |
263 |
Diesel is a petroleum-based fuel with a high energy content - helping diesel go further per gallon than most otherRefiners reduced the sulfur content in diesel fuel by 97 percent. This
new, ultra-clean fuel is important because sulfur tends to hamper
exhaust-control devices in diesel engines, like lead once impeded the
catalytic converters on gasoline cars. Just as taking the lead out of
gasoline in the 1970s enabled a new generation of emissions control
technologies that have made gasoline vehicles over 95 percent cleaner,
so will removing the sulfur from diesel help usher in a new generation
of clean diesel technology.
Advantages and Disadvantages of the different fuel types.
PROPANE |
Advantages:
- Long shelf life
- Clean burning
- Easily stored in both large tanks or in
smaller 5 - 10 gallon cylinders
- Obtainable during power outages - gas
stations may be unable to pump fuel during an area wide
outage
- Home delivery available for larger tanks
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Disadvantages: - Pressurized cylinder of flammable gas
- Fuel system is more complicated (increased
possibility of failure)
- Larger tanks are not aesthetically pleasing
(unsightly)
- Fuel system plumbing results in higher
installation cost
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NATURAL
GAS |
Advantages:
- Unlimited fuel source - refueling not necessary
- Clean burning
- Available during power outages
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Disadvantages: - May be unavailable during natural disasters
(earthquakes, etc.)
- Lower power output (30% less BTU's per
unit than gasoline)
- Fuel system plumbing results in higher
installation cost
- Not available in many areas
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DIESEL |
Advantages:
- Least flammable fuel source
- Easily obtained
- On site fuel delivery available
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Disadvantages: - 18-24 month shelf life
- Installing large storage tanks raises
cost of system
- May not be available during power outages
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GASOLINE |
Advantages:
- Common fuel source - easily obtained
- Increases portability of smaller generators
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Disadvantages: - Highly flammable
- Short shelf life (approximately 12 months)
- Storing large quantities is hazardous
- May not be available during power outages
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