Total electrification of IR tracks by 2022 appears to be overambitious target. However there are many benefits of electrification which can be reaped in much better way than is presently done:
(1) Use of 3 phase propulsion technology with regeneration facility for locomotives as well as suburban trains to reap financial benefits of regenerated power in addition to reduced wear & tear of train braking systems.
(2) Using electric train sets with quicker acceleration/ higher speeds to reduce journey times and increase sectional capacity.
(3)...
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Cost of fuel for electric traction is much lesser than diesel traction, so large scale electrification can reduce the operational costs and improve profitability of Indian Railways.
(4) Freight share which was 90% at the the time of independence is continuously falling and now it is about 30%. Going for electrified DFCs to run heavier and longer freight trains and accordingly rationalising the freight rates are a must to recapture freight traffic lost to roadways. Going in for Roll On Roll Off and railroaders in a big way in order to share freight traffic with Roadways is need of the hour..
(5) Once % of electric traction increase, the remaining small stretches of diesel traction shall prove even costlier.
(6) However, IR shall have to maintain some diesel locos to take care of emergent situations. Or dual power (Electric +Diesel locos need to be developed)
(7)IR have most of its tracks saturated with high traffic and electrification suits to tracks with high traffic density.