Page 247 - 05. Subyek Teknik Mesin - Automobile Mechanical and Electrical Systems Automotive Technology Vehicle Maintenance and Repair (Vehicle Maintenance Repr Nv2) by Tom Denton

2
Engine systems 231

Figure 2.304 Piezo common rail injector

Figure 2.305 Common rail injection combustion

2.5.4 Alternative fuels

The use of an alternative fuel can lessen dependence upon oil and reduce
greenhouse gas emissions. There are several alternative fuels and each of these
is outlined briefl y in this section.

2.5.4.1 Ethanol
Ethanol is an alcohol-based fuel made by fermenting and distilling starch crops,
such as corn. It can also be made from plants such as trees and grasses. E10 Key fact
is a blend of 10% ethanol and 90% petrol (gasoline). Almost all manufacturers Ethanol is an alcohol-based fuel
approve the use of E10 in their vehicles. E85 is a blend of 85% ethanol and made by fermenting and distilling
15% petrol and can be used in fl exible fuel vehicles (FFVs) ( Fig. 2.306 ). FFVs starch crops, such as corn.
are specially designed to run on petrol, E85, or any mixture of the two. These
vehicles are offered by several manufacturers.
There is no noticeable difference in vehicle performance when E85 is used.
However, FFVs operating on E85 usually experience a 20–30% drop in miles per
gallon owing to the lower energy content of ethanol ( Fig. 2.307 ).

There are some advantages and disadvantages of using ethanol:
Advantages:
lower emissions of air pollutants
●
more resistant to engine knock
●
added vehicle cost is very small.
●