The rapid industrialization has increased the demand of fossil
fuels more than ever. But fossil fuels reserves are depleting at an
alarming rate around the globe. The new reserves found using the
state of the art technologies are not enough to meet their
increasing demand. Therefore, there is need to find alternative
resources. On the other hand, the fuels used in transportation are
subjected to increasingly stringent emission regulations. In this
pursuit it is urgently needed to replace fossil fuels along with
keeping the environment clean. Research efforts have been directed
towards finding alternative economical fuel sources and thus
reducing the dependency on fossil fuels. These researches have led
us to alternative and economically viable fuels which are also
environment friendly. Among the proposed alternative fuels for
diesel engines, the biodiesel and diesel–ethanol/bioethanol blend
has gained much attention in recent years. This attention is due to
the fact that both of these are renewable energy carriers and can
be produced domestically. Moreover, studies have shown that
reduction in CO, unburned hydrocarbon and PM emissions from
diesel engines can be achieved using these renewable fuels