jump to navigation

Myth Buster – Diesel and Electric Locomotives November 16, 2013

Posted by Ramnath Rangaswamy in India, Indian Economy, Logistics, Railways.

ImageAre you one of those who believe that;

Electric locomotives are less polluting than Diesel locomotives;

Electric locomotives are technically superior to Diesel locomotives;

Steam locomotives to Diesel locomotives to Electric locomotives is the natural technological progress;

Diesel locomotives deplete our foreign reserves since bulk of the diesel is imported;

If you have answered YES to any of the questions above then please read on. Many misconceptions will be cleared and clarified.


When you see diesel locomotive hauling a train you see smoke coming out of the chimney while an electric locomotive chugs along along without any smoke. This would lead you to conclude (wrongly conclude) that diesel locomotive are polluting while electric locomotives are non-polluting.

This is similar to cleaning your house by throwing your garbage out on the road and claiming your house to be clean while complaining that the road is dirty. What does this analogy have to do with Electric locomotives and Diesel locomotives?

To compare like to like, the pollution at the power plant that produces the electricity needs to be compared to the pollution generated by the diesel locomotive.

Based on analysis, the results of the pollutants in gms/ bhp-hr is as below;

Particulate Emission SOx NOx HC CO
Diesel Locomotive 0.45 0.78 10.44 0.02 2.80
Electric Locomotive 0.51 3.38

Source: Diesel Traction – The Environmental Friendly Option ; AK Kathpal, RDSO

url: irsme.nic.in/files/dsl-kathpal.pdf

As the table above shows very clearly and obviously, an Electric locomotive is more polluting than a Diesel Locomotive.

Availability of Electricity

The Indian Railways uses about 11 billion units of electricity per year (or about 1300MW) about 1% of the electricity produced. However, given that India is short of power, by about   14,000 MW, the Indian Railways, if it had electrified only the routes that justified electric traction, could have reduced the shortage of power by about 5%.

5% may seem small but to put in perspective this could have lit up 650,000 homes.

What this electricity shortage also does is encourage use of inefficient diesel generating sets and diesel pumps.

When I say inefficient, I mean inefficient compared to a diesel locomotive on Indian Railways which is micro-processor controlled and which meets Euro 2 or CPA – 2 standards.

This in turn means more imports of crude oil which is then put to in-efficient usage in pumps and diesel generators. Had electrification been limited to the routes justifying electric traction, the electricity shortage would have been less and less number of in-efficient pumps and diesel-generating sets would have been used.


Is Electric locomotive operations cheaper than Diesel locomotive operations?

Before I answer that question, let me step back. Electric locomotives have a high capital expenditure but a low operations (or running) expense. The capital expense is high because of high initial cost for the equipment ; overhead electric catenary, sub-stations, transformers have to be constructed for electric locomotives to operate. When the traffic is high (Gross Tonne Kilo Metres, GTKM) then it makes economical sense to have electric traction as the capital cost to setup the electric equipment is divided by a larger amount of traffic and the lower running costs justify the investment.

In the Indian Railways context this threshold traffic in GTKM per year was fixed as 47 million GTKM per year. The irony is that only a small % of the electrified routes make the cut according  the criteria. In fact there are routes that have been electrified that have negative ROR!

To explain this concept, let me take an Indian example.

Diesel in India is cheaper than Petrol -why this is so and the vitiated reasons behind this is another story. But diesel cars are more expensive than petrol cars ie, capital cost is high. Maintenance costs of diesel cars is more than petrol cars. Diesel cars are more fuel efficient than petrol cars ie Operating Costs are lower. Given this data, people in India buy a diesel car only when their usage of the car is more than a certain kms/ month or kms/year similar to GTKM on Railways) which justifies a higher capital cost but lower running expenses. What would you call someone who has all this data but buys a diesel car despite not having the minimum usage to justify a diesel car.

Railways across the world which are electrified have a higher operating ratio (ratio of expenditure to earnings)  France: 44% electrified and operating ratio 184%, Italy: 59% electrified and op. ratio 200%, Sweden: 59% electrified and op. ratio 169%, Bulgaria: 63% electrified and op. ratio 325%, Austria: 59% electrified and op. ratio 205%, and Amtrack (USA) is 100% electrified with an op. ratio 146%.

Railways which use diesel traction have lower operating ratios: USA 0.9% electrified and operating ratio – 81%; Canada 0.1% electrified and op. ratio 86%, Australia 9.6% electrified and op. Ratio 89%.

An individual can be excused for making a mistake. But what about the Indian Railways  which has made such a colossal blunder at the cost of the nation.

So how has this wrong decision impacted the Indian Railways and India?

Indian Railways loses an estimated Rs 2000 Cr* (Rs 200 Billion or Euro 2 billion) every year, because of this wrong decision. This Rs 2000 Cr could have been used to reduce freight costs or improve  the railway infrastructure.

*Jal Khambata – Railway’s Electrification Mania


Also from a strategic and security standpoint, why would anyone electrify routes close to the border areas? Sub-stations and overhead wires if destroyed, are more difficult to restore.

What is the reason for this mindless electrification?

Politicians believe that getting electric traction to their constituency can be touted as progress and leveraged for votes. The contracts of maintenance of over head equipment, sub-stations is worth big money and hence there are many vested interests.

So the next time you see a train hauled by an electric locomotive and think of how clean and non-polluting it is, think of all the smoke and pollution from the power plant. And also think of all the unlighted and dark houses who have been robbed of electricity because of this mindless electrification.

Hope this has cleared some of the myths in your mind regarding Electric locomotives and Diesel locomotives.