How Much Horsepower Does a Modern Locomotive Have?

How Much Horsepower Does a Modern Locomotive Have?

Locomotives have come a long way since their steam-operating days. Now, most trains are manufactured using diesel-fueled engines, which are much faster and efficient compared to their predecessor. Furthermore, electric locomotives are experiencing a significant increase in demand, predicting a whole new era for the industry.

A modern locomotive can have anywhere from 1000 to 18,000 horsepower, depending on the power source, model, and year of production. The average power of a train engine can vary greatly, but almost all options offer a level of strength and durability that would be unthinkable a few decades ago.

In the following sections, you’ll find out more about the average horsepower of a modern locomotive and how it is able to work so efficiently. You’ll also learn about some of the most powerful locomotives in the world today, whose power will leave you speechless.

locomotive horsepower

The Average Horsepower of a Modern Locomotive

Most modern locomotives work using a diesel engine, but the newer versions are using electricity more and more as a power source. Depending on the application, the average horsepower of a contemporary model can easily surpass the 10,000 hp mark. 

When discussing the power of an average train, this considers only commercial cargo and passenger trains. Micro and macro versions can often skew one’s perspective when it comes to a standard number that can accurately describe a locomotive’s strength. 

All diesel trains work through a continuous connection between their engine and an electric generator (either a DC or AC). The generator uses the power produced from the motor and converts it into an enormous amount of current, which allows the locomotive to usually operate at 3000-5000 hp. 

As you can see, although the minimal and maximal power of a modern train engine can vary significantly, the average is closer to the lower end of the spectrum. This doesn’t mean that current models aren’t working as efficiently as they could. 

Instead, it implies the massive potential of electric versions expected in the future.

These statistics and measurements are based on traditional, single-locomotive trains. Modern multiple-unit trains are becoming widely popular due to their increased strength and other operational advantages.

Most of these alternatives use electricity as the power source of choice, although diesel versions still exist. They are still not as widespread as their traditional counterparts, as they remain costly to build and operate given the current manufacturing conditions.

Despite this, significant efforts are being made to bring this mode of transportation into mainstream popularity, as it can significantly increase the efficiency of modern trains. 

modern electric locomotive

How Does a Diesel Locomotive Work?

Diesel locomotives work through a cycle that starts with diesel ignition. This process provides power to the pistons, which are connected to an electric generator. Using the transmitted power, the generator produces enough energy to supply the motors that turn the wheels of a locomotive.

Diesel locomotives were one of the most influential inventions of the early 1900s

They are one of the most powerful and energy-efficient types of engine used in the train manufacturing industry today, which has led to their century-long popularity. Although they have improved and evolved throughout the years, the premise of the machine remains the same. 

The reason why diesel locomotives go through this process with such high efficiency, especially when compared to gasoline-powered engines, is their impressive compression ratio. The high ratio between the volume of their cylinder and its headspace makes them about 20% more efficient than their gasoline counterparts.

What Are Diesel Locomotives?

Diesel locomotives are self-powered machines that pull a train attached to them using their powerful internal combustion engines. This type of engine works using diesel as a supplier of power, the ignition of which transmits energy through a generator that passes it onto the locomotive’s wheels.

Diesel engines are unique in the way they operate. 

Unlike most other alternatives, they don’t rely on having any direct mechanical connection created between the motor and the train wheels.

The Operational Process of a Diesel Locomotive

The primary function of a diesel motor is to transmit power to an electric generator, which is usually an AC on most contemporary models, not the wheels themselves. 

Therefore, the production of the rotational torque used in this process happens in this generator.

Diesel locomotives are manufactured to operate based on some principles applied in electric locomotives, which, believe it or not, were invented earlier

For this reason, you’ll often find the technique used by diesel motors referred to as “diesel-electric.” This process is immensely well-thought-out and much more complex than you’d find on an earlier option. 

Every part of a diesel engine needs to operate perfectly as an independent piece of equipment as well as in immaculate synchrony with one another. This quality allows the motor to run efficiently and reliably for an impressive amount of time. 

Its self-reliance in power generation is one of the main reasons this model has gained so much popularity during the last century. 

But there are many other factors that have made this power source so sought-after by manufacturers. Diesel engines have lower volatility levels, lower costs and are very commonly accessible, making them an ideal option for worldwide use. 

The entire operational process of a diesel engine goes through these steps:

  • A fuel tank is filled with diesel through an electric fuel pump. The substance is stored in this area to be used as a power source later on.
  • The reserved fuel gets ignited through intense heat generated through the air compression that happens during the upward strokes of the cycle. This process pushes the motor’s piston down, whose movement turns a crankshaft. 
  • The crankshaft is connected to 12 cylinders whose consequent movement contributes to the creation of mechanical power. The engine’s pistons are connected to a generator that converts this mechanical power into electricity.
  • The generator passes the converted electrical power onto established circuits, distributing this energy to the traction motors. Each of these motors is geared directly to a pair of driving wheels, which, as you can imagine, start turning and allow the locomotive to move effortlessly.

This approach allows engineers to directly adjust the power output to their liking by electrically controlling a throttle. The more this mechanism is opened, the more fuel can be injected into the motor’s cylinders, from where you can see that the whole power creation process starts.

The increased fuel injection will translate into the creation of a higher amount of mechanical power. This affects every other engine component until the movement force of the wheels is increased.

modern diesel locomotives

The Difference Between a Diesel and a Traditional Locomotive

The superior efficiency of a diesel locomotive compared to a traditional one is now accepted as a fact throughout the whole industry. 

This is why it is crucial for you to understand the key differences between the two models that make one superior to the other. Better understanding these differences start with learning how each of these alternatives works.

Traditional engines rely solely on mechanical energy to transmit power to the locomotive. This can often be a crutch, as mechanical operations tend to be fragile and easy to fail. On the other hand, we have modern diesel-electric models which use both mechanical and electrical energy to sustain their operations. 

This setup not only gives a better overall energy output but is also more reliable and durable under challenging conditions.

The Transition From Steam to Diesel Locomotives

The transition from steam to diesel locomotives, alternatively referred to as “dieselization,” took place between 1930 and 1960. 

During this three-decade window, the train manufacturing industry was fully revolutionized, giving production companies the capacity to explore possibilities that were never thought possible before.

The diesel alternative first started making its first appearance during the 1930s. Although it was notably less powerful than its steam-fueled counterpart, it started gaining remarkable popularity among users and manufacturers.

Several reasons contributed to this shift. 

First of all, the newer diesel models were much smaller and lighter, making them a more manageable piece of equipment to manage and work with. Their smaller size also meant that they would be quicker and easier to produce and transport to buyers.

But this decrease in dimensions was hardly the only reason for this switch in preference. The diesel motor is one of the most efficient ways of producing power and energy, allowing manufacturers to achieve the same energy output for a fraction of the cost.

Think about it this way: With diesel-fueled alternatives operating at 3-4 times higher efficiency rates than steam engines, conductors had to stop far less often to refuel, saving significant costs and time in the process.

Furthermore, it was observed that the combination of mechanical and electric power resulted in a far more reliable performance from locomotives, who were running more smoothly for more extended periods of time. 

This meant that companies would be able to cut down their costs even further due to a significant decrease in maintenance and inspection needs. 

With the economic recession that followed the Great Depression during the 1930s, railway companies were looking for efficient ways to cut down costs by any means possible. Therefore, the shift to diesel was immediate, as many companies recognized the economic benefit it could present to them. 

From then on, manufacturers have been able to spread out costs even more efficiently while continuously improving the performance of diesel-fueled locomotives, which have become the industry standard today.

electric locomotive modern
Charles Warren

The Shortcomings of Steam Locomotives

There are several shortcomings when it comes to steam-powered locomotives, which affected the complete transition to newer diesel-based models. These shortcomings are some of the main factors that have led railway companies to look for more efficient alternatives.

Their Power Can Affect Performance Negatively

Although steam-fueled locomotives are well-renowned for their impressive power, this amount of strength can often become a crutch. 

The reason for this is it is not always used efficiently and consistently, nor can it ever be fully applied to the rail. Furthermore, bigger, more extensive motors lead to the vehicle being bigger and bulkier overall, which negatively affects its agility and ability to be managed and maintained.

Operating on a Constant Force

The second disadvantage comes from steam-powered engines being a machine that operates on the constant force. This means that the energy this engine exudes will be the same no matter the vehicle’s speed. 

You can see how this operational approach can be very inefficient and wasteful when it comes to power-fueling resources.

Therefore, although steam locomotives are generally more powerful compared to diesel alternatives, their strength is not used as efficiently when operating the vehicle. The power difference is rendered insignificant because the final energy output is what ultimately matters.

Inefficient Size

On another note, steam locomotives being overall bigger and heavier means that they develop more resistance, aside from being harder to manage and transport. Not only will they require more power to operate, but they also operate much slower than diesel models, as they need a much longer time to accelerate. 

Limited Speed

Yet another shortcoming of this engine lies in the fact that power and energy extruded are limited depending on boiler capacity

The piston speed increases when you’re trying to accelerate a steam-fueled engine. This means that the pistons will start making more strokes in less time, but each stroke requires steam to happen. 

At a certain acceleration rate, the boiler won’t have the needed capacity to provide the pistons with enough steam to sustain their increased movement pace. When this happens, the steam pressure will start to drop, which will, in turn, slow down the movement of the pistons, which will automatically decrease the speed of the locomotive. 

Therefore, the rate you can reach using a traditional engine will always be very limited and harder to control. 

This is why, during the transition to diesel locomotives, speed was one of the operational factors that experienced the most significant improvement. Because not only was the speed limit with traditional models severely limited, but conductors often had to operate well below it. 

If the train reached a high acceleration rate, the falling boiler pressure was bad practice. 

Therefore, they had to make sure to prevent the machine from reaching this breaking point. This meant moving at a speed marginally lower than the limit to err on the side of safety.

Although some may think this problem can easily be fixed by installing a boiler with a higher capacity, added mass in this already heavy machine will only make the previously-mentioned disadvantages more significant. 

Pressure Caused by Speed Limitations

These speed imitations can cause many more issues along with those regarding timing. As I mentioned, as the locomotive accelerates, the pistons will start moving faster in a back and forth motion. 

This also means that there will be less and less time between each stroke for the steam to move and supply the pistons with adequate power. 

After a certain point, this movement restriction will inevitably lead to a steep pressure drop, which means that the force produced by the engine will significantly decrease. This can cause some steam to be trapped in the cylinder, valves, or exhaust nozzles, which will, in turn, increase the pressure inside these components. 

This is a practice conductors actively tried to avoid, as this “back pressure” could quickly lead to the malfunction of the whole vehicle.

Overall, steam was simply an inadequate choice to maintain the railway industry for an extended amount of time. Its flammability, high maintenance requirements, imbalances, and limitations made it far too inefficient to be kept as the primary energy source in modern locomotives.

Therefore, even though diesel, considered by itself, can be costlier and less powerful than steam, its unparalleled efficiency makes its usage much more affordable for companies. This difference becomes even more apparent when you consider managing, handling, maintenance, and transportation costs. 

Furthermore, you can understand why lighter, faster trains are constantly being prioritized over bulkier counterparts, as they improve on the critical factor of efficiency. These are just some of the many reasons why the invention of the diesel locomotive revolutionized the rail industry with such a significant impact. 

This model introduced the use of a more functional and cost-effective approach to railway operations, which is why it is still leading the industry today after almost a century after its invention. 

Its lightweight and easy to achieve acceleration rates are very well-aligned with modern views of what transportation should become. This is why although electric locomotives have gained a lot of popularity during the last few years, hybrid models are here to stay for a long time.

diesel electric locomotive
Ian. A McCord

Electric Locomotives

Although electric locomotives are, in fact, an earlier invention than the diesel engine, they have never soared in popularity quite like today. They are gaining a tremendous amount of traction in the railway industry and are often seen as the dominant technology of the future.

Although the idea behind it has been around for centuries, manufacturers now have access to the technology and the means to make high-tech electric locomotives an integral part of the industry. 

In this particular model, the engine is powered through electricity conducted by overhead lines, as you may have seen in many contemporary trains. Electric locomotives are one of the most efficient types of motors that provide levels of power unwitnessed before on terrestrial vehicles.

The impressive power of these motors can be understood simply by comparing the average horsepower of a diesel engine, which is already highly efficient, with the horsepower of an electric alternative. 

While the former, as I mentioned, hover at an average of about 3000-5000 hp, the latter reaches an average of 6000-7000 hp.

I want to note that this estimation is simply an average and that particular models can reach much higher strength levels, which are all supplied by electric power. 

One of the most notable advantages that this type of power supply offers to a locomotive is the fact that the power output is not dependent on the speed level. This allows the vehicle to apply full strength even when stopping, which makes the motion much more quick and efficient.

This quality offers a notable improvement in the operational quality of a locomotive, and it is an absolute must in modern models.

Electric Locomotives Efficiency

One of the main advantages that has drawn manufacturers when it comes to electric locomotives is their unparallelled efficiency. Most often, these types of engines work with an efficiency level of more than 90%, which, as you can see, is a stark difference from other models’ 20-45%. 

Not only are these motors highly effective themselves, but this quality can even be further enhanced with the use of regenerative braking. 

This mechanism allows the engine to restore energy during braking. The added energy retention can be repurposed to produce an even higher power output, increasing the locomotive’s overall efficiency. 

Despite the high level of strength produced due to this impressive level of effectiveness, these locomotive models are still light, quiet, and easy to operate, as there’s no need for a big bulky motor, which could weigh them down.

Their lightweight and agility also contribute to the lowering of maintenance costs, as the replacement of most mechanical processes means there’s a lower chance of operational failure. 

With that said, although electric locomotives are so impressively efficient and have much lower operational and maintenance costs compared to other alternatives, their main drawback is that their initial infrastructure costs can be unaffordable for many. 

This is one of the main reasons why you won’t see these models as often as you’d expect by now.

Still, electric trains are widely thought to be the vehicle of the future, as they fulfill all the expectations set on modern modes of transportation. 

Due to increasing concern over environmental issues, more efforts are being made to develop an infrastructural technology that could make these locomotives more accessible in all parts of the world.

modern diesel
Richard Dyke

What Are the Most Powerful Locomotives in the World Today?

The railway industry has come a long way since its steam locomotive days. As you’ll see, modern engines can provide unprecedented power levels due to their high and constantly improving efficiency. 

The three most powerful locomotives in the world today are Novocherkassk 4E5K, Bombardier IORE, and Datong HXD2. All these models range from 13,410 to 17,838 horsepower.

Novocherkassk 4E5K

The Russian Railways’ one-of-a-kind model has set a new golden standard when it comes to engine capacity with a horsepower of 17,838. Novocherkassk 4E5K currently holds the crown as the most powerful locomotive in the world. 

To put its impressive strength into perspective, this amount of energy is enough to fully supply power to over 2,000 average homes or a small village. This energy output is produced from a hybrid diesel-electric engine with powerful generators responsible for the power transformation.

The pulling force applied by this motor is unparalleled in this day and age. 

Still, with this rate of progress and evolution in the railway industry, you can expect this level of strength to be more available in the mainstream market sooner than you think. 

Bombardier IORE 

With a whopping 14,483 horsepower, this class of 34 electric locomotives rightfully holds second place among the most powerful locomotives on earth. The electric locomotive has an impressive maximum speed considering its heavier weight. 

Bombardier IORE has gone through consistent improvements since it was first introduced in 2000.

The current version offers the most significant increase in power and durability, with many more further improvements to be expected from the Swedish manufacturer. These qualities were crucial during the production of the locomotive, as it was first designed to be used by local miners.

When the final product came to light, manufacturers saw the opportunity to market it all around the world as a powerful vehicle indicative of a modern era.

Datong Electric Locomotive HXD2

The Datong Electric Locomotive HDX2 is a Chinese import with a horsepower of 13,410. This vehicle was designed for weighty freight applications and to be able to substitute the power of three separate locomotives.

Its main characteristics are durability and ease of operation, even in the most difficult circumstances. This locomotive can normally function even in extreme weather conditions, making it ideal for the transportation of goods throughout the most challenging locations.

With the first version being released in 2007, this model has seen constant improvement before coming to the point it is today. Its agility and durable structure have made this model a favorite among manufacturers in the area, as it is one of the most-used vehicles for the transportation of coal. 

This locomotive sets itself apart through the well-thought-out usage of technology which makes the model an impressive feat to witness. With highly-accurate computer control and monitoring systems, this creation is an exciting indicator of the direction in which the railway industry is heading.


Today, modern locomotives have a much higher strength and durability than anyone would have thought possible just a few decades ago. Although the horsepower can greatly vary from one model to another, some of the most impressive modern locomotives can reach up to 18,000 hp.


Lifelong Rail Enthusiast and Owner of Worldwide Rails

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