Skip to content

Prime Movers | How Are Prime Movers Classified? | 10 Explanation On Why Engine Prime Movers Is So Important.

Prime Movers and Different Forms of Energy Resources

This article provides the fundamental details of the different types of prime movers used to produce mechanical energy in our daily lives. The different energy sources used by primary movers are also included.

Introduction to Prime movers

In the early stages when no technological progress or inventions existed in the field of mechanical machinery development, humans must depend on their physical strength and animal in order to perform various works. Now it has been possible to satisfy various needs in daily life and work with the development of engines and a number of energy sources for generating power from the engines.

The widespread use of mechanical power is the distinguishing characteristic of our culture, which distinguishes it from all previous civilizations. Prior to this, animals were taught to assist humans in a variety of tasks, such as traveling and agricultural work. Following this, the wind energy industry saw a revolution. Ships, for example, travel on the force of the wind. After a period of time, the use of electricity generated by flowing streams began.

When humans discovered how to transform the heat generated by chemical processes into mechanical energy, it completely changed the world. Heat engines are the machines that have been used for this purpose, and the whole system of machines that were employed for this purpose is referred to as a prime mover.


Prime movers definition:

‘Prime mover is a device that uses and converts the energy from natural sources into mechanical energy.’

The primary source of power is the literal meaning of the term “prime mover.” It refers to all of the equipment that generates power for the purpose of completing various mechanical tasks.

Technically speaking, it is a collection of devices that convert energy from thermal, electrical, or pressure to mechanical form, which may then be used in a variety of sources to do mechanical work. Engines and turbines are examples of such devices.

Prime Movers’ illustrious past

The rifle was the first prime mover to have a revolutionary impact on society. They operate on the basis of the heat engine concept. It was difficult to realize that the most significant difference between the bow and the gun was the gunpowder replacement for the bowman’s muscles. But this was the case. This resulted in a revolution since the weapon was initially inferior to the bow in terms of range and precision; but, with time and effort, the weapon’s range and accuracy improved to a more advanced level. Even now, efforts are being made to improve the efficiency of this type of prime mover.

Prime Movers have reached certain milestones.

Another revolution began with the advancement of steam engine technology, thanks to the work of James Watt. By including an intermediate working fluid into the design, he altered the idea. It was as a result of this enhanced technology that the products of combustion did not have a direct impact on the mechanism’s working components. It wasn’t long before they began to replace the piston engine’s old-fashioned working principle with the more modern turbine engine, which could harness the power of steam.

When it comes to power generating, three major rivals in the area of mechanical power production are brought into the picture. The steam turbine plant, the diesel piston engine, and the gasoline piston engine are the three types of engines.

Around the turn of the nineteenth century, steam turbines surpassed all other primary generators of electricity as the most significant prime movers. They were also extensively used in the production of electricity for maritime boats. These kinds of engines, on the other hand, had a significant disadvantage: they were incapable of producing high-pressure, high-temperature steam.

As a result, new, large, and costly steam-generating equipment, such as the boiler and nuclear reactor, were developed to meet the demand. They are designed to generate steam as an intermediate working fluid in the course of their operation.

Many more types of power generating systems were developed later on. Those systems are more advantageous since they eliminate a stage in the process of converting water into steam. These companies manufacture the hot gases themselves, and the hot gases are utilized to drive the turbine directly. Piston diesel generators are an example of this kind of power generation. In a number of places, these devices have begun to take the place of large power plants in the production of electricity.

In the early days of aviation, gasoline engines were utilized to propel aircraft. It was also during this time period that a device known as the gas turbine was developed, and it eventually replaced the use of superchargers based on piston engines.

In the decades after World War II, the gas turbine saw its most significant development. They were known as turboprops because they were powered by shaft power technology. Once this was accomplished, the development of turbojet engines for aviation applications began, with these engines being based on mass airflow rather than shaft output. The gas turbine, on the other hand, is still in widespread usage throughout the globe because it may be utilized in a broad range of applications.

A quick summary of the prime movers

Earlier attempts at power generating systems had some benefits and some drawbacks; but, only a few of them were focused on the design and construction of efficient gas turbines, which was a significant step forward.

Gas turbines, which are the primary generators of energy today, are the most efficient power plants available in every aspect. They feature a high level of dependability, use less lubricating oil, and have a good power to weight ratio.

Different energy sources used by prime movers:

Prime movers use various energy sources. The following are the different sources:


This is a key energy source. It releases heat energy if any fuel is consumed. The fuel energy is dependent on the fuel type being burned. Various fuels have different calorification values and are released by the fuel on the basis of heat. This heat energy is then transformed into mechanical energy.

In a boiler, coal, oil, or nuclear fuels are burnt to generate high-pressure, high-temperature steam under high pressure. After that, the potential energy contained in the steam is transformed into mechanical energy by means of axial flow steam turbines.

The governor system of a turbine is responsible for a wide range of tasks, such as the ones listed below:
• Control of speed and load

• Control of Overspeed

• Overspeed trip

• Start-up and shutdown of the system

Water from the River Streams/Ponds/Lakes:

Another useful and widespread energy source. The latent energy is present in water falling from a certain height. When it reaches the primary mover, this potential energy is translated into kinetic energy. The primary mover used here is the power-generating hydraulic turbine. The other use is to produce steam (i.e., a thermal power plant) in a boiler with the streaming of water. Again, steam is used to produce mechanical power in steam turbines and steam engines.

Hydraulic turbines are devices that transform the kinetic energy of rivers into mechanical work at the shaft of the turbine. River water energy and tidal (wave) energy are both renewable sources of energy. They are the products of a water circuit in nature, and they are gravitational in nature, respectively (tide energy).

Hydraulic turbines are among the most ancient types of primary movers ever invented by man.  Water serves as both the energy agent and the working fluid; in general, the kinetic energy of water is used. Wind turbines are identical to hydroelectric turbines, except that the kinetic energy of the wind air substitutes the kinetic energy of the water. Wind turbines, on the other hand, will be handled individually owing to the many differences between them. Hydraulic turbines are often used as prime movers, or motors, in their applications.

There are also reversible hydraulic machines, which may be used as either a turbine or a pump depending on the application. These pumps are often referred to as hydraulic turbine pumps. There are also hydrodynamic transmissions, which are composed of two or more hydraulic machines that are easily placed on a single frame. They function in the same way as mechanical gearboxes, but they are under active control.

TurbineTypeHead (m)InventorTrajectory
TangentialImpulse>300PeltonDesigned in the transverse plane
Radial-AxialReaction<50FrancisBent into the axial plane
AxialReaction (Propeller)<50Kaplon, Strafflo, BulbBent into the axial plane


In recent years, atoms have been used as a rich fuel and a good source of energy for energy development. Heat energy is generated through atomic fission or fusion. The heat energy is transformed by turbochargers into mechanical work.

Wind Energy:

In recent days, this power source has been commonly used, since it is easily available everywhere. It is a type of electricity produced as green energy.

Windmills have been in operation in nations such as Holland, Denmark, Greece, Portugal, and other European countries for centuries. The most desirable sites are found in the mountains, near the sea, or on the ocean’s edge (or offshore). Wind speed rises with altitude and becomes more uniform as altitude climbs. Designs with a greater height/turbine diameter result in more uniform flow and better energy extraction than those with a smaller height/turbine diameter. However, this comes at the cost of more costly towers that are exposed to greater structural vibrations.

In addition to location, height above the ground, and magnitude of local terrain imperfections, the wind’s uniformity, and intensity are determined by the wind’s speed and direction. In general, wind-driven airflow may be classified as turbulent in nature.

Solar energy:

The source of energy supply is free too, provided that it is captured and used properly to produce electricity. It is often classified as a clean green energy source.

Types of Prime movers:

Prime movers are categorized according to the energy sources they use. The following is the classification:

1)Thermal prime movers:

These are the primary movers that produce power using thermal energy from the source. The following are given some thermal primary movers:

Heat engines:

These engines are used to produce mechanical power from different fuels such as petrol, gasoline, oil, coal, etc.

Heat engines are two types:

-External combustion engines:

1) Reciprocating steam engines
2) Steam turbine
3) closed-cycle gas turbine

Internal combustion engines:

1) Reciprocating I.C. engines
2) Open cycle gas turbine


This prime mover uses the fission or fusion technology of the atoms to produce mechanical energy from thermal energy. It is found mostly in nuclear plants. Some radioactive elements such as uranium and thorium have been used for this fission, or the fusion process in a nuclear reactor.


Heat energy is derived from a certain depth of this kind of prime mover, or the hot portion of the earth below the earth’s surface, and then transformed into mechanical power by the required engine.


Biogas is primarily produced from garbage waste or any other waste used in a biomass plant to produce electricity through prime movers.

Solar energy:

Solar energy in the form of radiation or electromagnetic waves comes into the world. Using solar panels made of semiconductor material, this energy was trapped. This heat energy then becomes electricity.

2) Non-thermal prime movers:

Such primary movers don’t use heat energy for mechanical power. The non-thermal primary movers are as follows:

Hydraulic turbines:

This type of primary mover uses stored water power to generate electricity.

Wind power:

Wind energy is converted into power by means of a wind turbine.

Tidal power:

The energy from the ocean tides is transformed into power by a tidal power turbine.

Because there are so many differences in design, from topology to control, it is very difficult to provide a comprehensive categorization of prime movers. An automatic speed governor (in reality, an automatic speed control, and protection system) must be installed on the primary mover in order to correctly manage the speed of the machine.

It should be noted that the turbine is equipped with a servo motor that operates one or a few control valves that govern the flow of fuel (or fluid) through the turbine, thus regulating the mechanical power delivered to the turbine shaft.

FuelWorking FluidPower rangeMain ApplicationTypeObservation
Coal or Nuclear fuelSteamUp to 1500 MW/UnitElectrical power systemsSteam TurbinesHigh speed
Gas or OilGas (oil) + AirFrom watts to hundreds of MW/unitLarge and distributed power systems, automotive applications (vessels, trains, and highway, and off-highway vehicles), and autonomous power sourcesGas Turbine
Diesel engine
Internal combustion engine
Stirling engineWith rotary but also linear reciprocating motionWater energyWaterUp to 1000 MW/unitLarge and distributed electric power systems, autonomous power sourcesHydraulic TurbineMedium and low speed (>75 rpm)Wind energyAirUp to 10 MW/unitDistributed power systems, autonomous power sourcesWind or wave turbinesSpeed down to 10 rpm

2 thoughts on “Prime Movers | How Are Prime Movers Classified? | 10 Explanation On Why Engine Prime Movers Is So Important.”

  1. Pingback: 10 Useful Tips For SolidWorks Training (2021) - Everything You Need To Know

  2. Pingback: Different Types Of Prime Movers? All Answers

Leave a Reply

Share to...