Comparison Of Diesel And Electric Locomotives In The Transport Sector

Advantages and Disadvantages of Diesel and Electric Locomotives

Discuss about the Principles of Mechanical and Electrical Railway.

Since the invention of locomotives the transport sector has grown adversely. However, in the recent past the manufacturers have been working day in day out to better the industry. This has been seen by the invention of different types of locomotives; Locomotives that produce their power from fuel sources such as wood, petroleum, coal or even natural gas. While others use power from an external source as in the case of electric locomotives.

The invention of electric locomotives brought up an endless argument over which of the two (fuel and electric) is better, convenient and cheap. Despite the modernization of the diesel engine there’s been issues still lingering over the cost incurred in maintenance. The electric locomotive has not been left behind either, it has also been criticized it’s in expensiveness during setting it up.

The invention of this two types of locomotives lead to the death of steam engine which is rare to find in the world. This locomotive has since been upgraded to make them more fast, convenient and efficient. The rail network has been developed in various regions. It is majorly depended upon for transportation of heavy duty products such as minerals from mines, export and import goods management.

The locomotives have proven to be a good invention and are still in use up to now with major adjustments being done to meet man’s daily demands

The load being hauled in this scenario is heavy and will have a high impact on the locomotive. Therefore, a good and sustainable traction system should be used. A DC traction system will work best here. This traction system has varying operating voltages which are 600V, 750 V, 1500V and 3000V.

1. DC supply at 600-750V is applied at the city and for the suburban area
2. The power stations will provide DC supply at 1500- 3000

In both scenario, a single conductor or rail is used to feed power to locomotive while the rail tracks work as the return conductors. The overhead power cables are three phased and of high voltage. This voltage is then stepped-down and converted to a single phase low voltage using transformers. The resulting voltage is then to be converted into DC voltage using converters. This DC supply is then fed to the DC motor through a contact system. DC series traction motors are to be used in this system.

1.  The trains are to be loaded with heavy load and thus they will require frequent and rapid accelerations, DC traction motors work better at this as compared to AC traction systems.
2. This system uses less energy and power compared to AC unit when working under the same conditions of service.
3. The equipment used in DC traction system is cheaper, less heavy and of high efficiency.
4. Dc traction system causes no electrical interference when close to communication lines.

Electric engines are cheaper to maintain when compared to diesel engines. This is because the electric engines are lightweight and simple. Diesel engines are somewhat complex; they have a bigger number moving parts examples being pistons, valves, turbines, and chains. Electric engines only require an overhead cable to be powered and are therefore a little bit easy to maintain when compared to the parts of a diesel powered locomotive which require regular checks and maintenance.

Cost Comparison between Diesel and Electric Locomotives

The simplicity of the electric powered locomotive makes it more efficient and fast. Electric locomotives produce less heat and noise, thus most of the energy produced is used for forward motion. However, Diesel locomotives waste a lot of the energy produced in form of heat and noise, thus less energy is used for forward motion.

The technology used in electric locomotives is simple and straight forward. Energy is supplied by overhead cables and is brought down into the required unit by a simple transformer. As for the diesel engine, energy undergoes various steps of transformation making it too complex and inefficient.

Unlike diesel engines whose engines are complex and costly to construct; the electric locomotives bare simple power transformers. Diesel engines re heavy and less productive as they use more energy and are very slow.

Electricity can be locally produced by the coal plants compared to oil which is not available in all areas. Most areas are supplied with electricity and hence working with an electric locomotive will be much cheaper compared to diesel which we may have to import or buy. Fuel costs tend to fluctuate from time to time making the use of diesel engines expensive. Oil mines in the world are being exploited and would soon run out. Making use of electric locomotive would save oil for other transport sectors. This makes the use of a diesel engine more expensive and more demanding. We may conclude that; the use of electric locomotives saves on imports.

There’s less pollution when we use electric locomotives. This is because the locomotives do not produce noise nor smoke as they move. Diesel locomotives on the other hand produce smoke and noise which may be a nuisance I the city. Although the production of electricity by the coal industry in attempt to power the electric locomotive may pollute the environment, the pollution is only during production and not movement of the train.

They are therefore environmental friendly since they emit no gases at all. Electricity used for them can be generated from windmills or solar panels. This green energy saves money and also helps to conserve the environment since there’s little to no pollution at all.

Diesels locomotives have been burned from operating under the overhead traction cable by one of the investors at the mines. However, they can still be retained at the mines with limited life because;

Setting up an electrified loop would be costly. The cost required in setting up an overhead electric cable line is quite high. This would mean will have to set up a loading infrastructure to which will further increase the cost. It is therefore advisable to maintain the current diesel locomotive.

Maintenance Comparison between Diesel and Electric Locomotives

The cost of setting up several kilometers of traction cable may be equivalent to that of buying a new engine locomotive. The cost of purchasing the equipment and setting them up can be used to provide extra locomotives to transport the coal.

The mines have limited life. This means they may wear out soon and the mines will be deserted including the train truck. They are however reasonable hence the diesel trains can be used to haul the coal to the various expected points. If we invest in setting up traction cables for the electric train, we may encounter loses. It is therefore advisable to retain the current diesel trains as they are already in place.

Suppose we switch to electric locomotives; electric power will be needed to power up the trains. Hence this might lead to generation of electricity using the coal or rather purchase of power. The coal produced is reasonable but the mines would soon run short of coal. This means loss to the miner.

Land and space. Setting up of electric locomotives requires an overhead cable contact. These cables are supported by poles so that they can be at least five feet high. This set up consumes a lot of space and land. this also adds to the costs needed in setting up a traction cable. The cables also need to be raised high and protected from destruction by either wild animals, vehicles or human interference management.

They can still operate at the two mines and deliver the coal to the other electric locomotives for transfer over the electric traction cable. Coal can be loaded and transported to the loading center of the other investor before being hauled to their various destinations.

The two locomotives can work hand in hand to help haul the coal at the various destinations. The export operation would work best during the day. The other investor at the mines does not allow the hauling of coal over his rail using diesel locomotives. On the other hand, the other two mines are not supplied with electric traction cables. The diesel engines can operate from this two mines. The locomotives would haul coal from this two mines to the other mines with electric traction cables.

The other three mines have electric loops cables and also and also a loading infrastructure. The two diesel locomotives will be offloaded at this point. The coal will be loaded into the electric locomotives. The remaining coal at the three mines will be easy to transport since they are sited at an appropriate area where they are supplied with an electric traction system.

Efficiency Comparison between Diesel and Electric Locomotives

The haulage task for the thermal coal will be done at night. This is because the traction system traverses a city and also uses a traction system used by passenger’s train. The electric locomotives will be used in this case since there’s an electric traction system from the mines to the various power stations. The noise regulations in place would hinder the use of diesel locomotives.

If we do away with the diesels locomotive, this only means will have to make use of the electric locomotives. The export operation would require additional investment for it to be possible. This can be achieved if only we invest in constructing a traction system at the two mines where they do not exist. This would be costly but the only way to meet the demands of the contract. the power for this traction system can be obtained from the power plants to be supplied with coal.

Similarly, the export operation would be done during the day as it is advantageous. The haulage task for the thermal coal can be done at night.

Conclusion

The two locomotives can work together to meet the demands of the contract. the removal of the diesel engine in the haulage would lead to greater expenses. Similarly doing away with the electric locomotive would be inappropriate. The invention of electric train is not a reason enough to do away with the diesel trains. Most places are supplied with electricity but not all regions. This region with no electricity can make use of the diesel trains.

In the scenario provided above, the mines are supplied with rail tracks most of them with an electric traction system and it is therefore advisable to use the electric locomotive. However, the two mines with no electric traction system would require the use of diesel locomotives. If the diesels can’t be used, it is therefore a requirement that an electric traction system be set up at the two mines.

Before making a choice of what locomotive to use the cost and time factor are very important. They should be considered to avoid future regrets or loses.

Reference

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