In this post, you will learn about diesel power plant with its layout, components used in diesel power plant it’s working, advantages and applications.
Introduction to Diesel Power Plant
The diesel power plants are installed where the supply of coal and water is not available in sufficient quantity or where power is to be generated in small quantity or where standby sets are required for continuity of supply such as in hospitals, telephone exchanges etc.
These plants in the range of 2 to 50 MW capacity are used as central stations for small supply authorities and works.
The diesel power plants are generally used as follows:
- Peak load plant: The diesel power plant is mainly used along with thermal/hydroelectric plants as peak load plant.
- It is used as a mobile plant.
- These can be used as a standby unit to supply part load.
- These can be used as an emergency plant for communication and water supply under emergency conditions.
- The diesel power plant used as a Nursery station to supply power to a small town or city.
- Used as a starting station for starting the large steam plants.
- Used as a central station.
- Power Plant: Types, Factors, Choices and Terminology Used in Power Plant
- What is Power Plant Economics? It’s Cost of Power Generation and Calculation
Diesel Engine Power Plant Block Diagram
A simple diesel power plant as shown in the figure. The diesel engines are generally classified into four strokes and two-stroke engines. Generally, two-stroke engines are used for diesel power plants.
The compressor draws the air from the atmosphere and compressed. The compressed air is supplied to the engine through the filter for starting, where it is compressed by a piston in a cylinder. The fuel oil is supplied from the tank through the filter to the fuel injectors. The fuel injector injects the fuel into the cylinder and mixes with compressed air.
The injected fuel gets ignited and combustion takes place. This liberates the huge amount of energy which is utilized to run the generator to produce the electric power. The cooling water is continuously supplied to cool the engine and lubricating oil is supplied to lubricate the engine parts. The air intake supplies the air to the engine for subsequent operations.
The layout of Diesel Power Plant
The layout of a diesel power plant is shown in the figure. Air from the atmosphere is drawn into the compressor and it is compressed. The compressed air is sent to the diesel engine through the air filter. In the air filter, dust, dirt from the air is filtered and only clean air is sent to the diesel engine.
Fuel oil from the tank is passed through the filter, where the oil gets filtered and the clean oil is injected into the diesel engine through the fuel pump and fuel injector. The mixture of the compressed air and spray of fuel oil are ignited in the engine and the combustion takes place. The released heat energy is utilized for driving the generator, which produces power.
- Fuel supply system
- Air intake and exhaust system
- Lubricating system
- Starting system
- Cooling system
1. Fuel supply system
This system consists of a fuel tank for the storage of fuel, fuel filters and pumps to transfer and inject the fuel. The fuel oil may be supplied at the plant site by trucks, road, rail, tank etc.
2. Air Intake and exhaust system
This consists of a compressor, a filter for the supply of air and pipes for exhaust gases. Filters are provided to remove dust, dirt etc., from the incoming air. In the exhaust system, a silencer is provided to reduce the noise.
Followings are the functions of the air intake system:
- To clean the intake air supply.
- Is to silence the intake air.
- To supply the air for supercharging.
3. Lubricating system
Lubrication is essential to reduce friction and wear of the moving parts. It includes lubricating oil tank, pumps, filters and lubricating oil.
4. Starting system
For starting the engine initially, the various things used are compressed air, battery, a self-starter or electric motor.
5. Cooling system
This system provides proper control of water circulation all around the diesel engines to keep the engine temperature reasonably at a low level. The hot water from the jacket is cooled in cooling ponds and is re-circulated again.
Essential Components of Diesel Power Plant
The diesel power plant essentially consists of the following components:
- Air filter and supercharger
- Exhaust system
- Fuel system
- Cooling system
- Lubricating system
- Starting system
- Governing system.
It is the main component of the plant which develops the required power. The engine is directly coupled to the generator.
2. Air Filter and Supercharger
The function of the air filter is to remove the dust from the air which is taken by the engine. The use of the supercharger is to increase the pressure of the air provided to the engine to increase the power of the engine.
3. Exhaust System
This includes the silencers and connecting ducts. The temperature of the exhaust gases is sufficiently high, therefore, the heat of the exhaust gases may be used for heating oil or air supplied to the engine.
4. Fuel System
It includes storage tank, fuel transfer pump, strainers and heaters. The fuel is supplied to the engine depends upon the load on the engine.
5. Cooling System
This includes water circulating pumps, cooling towers and water filtration plant. The purpose of the cooling system is to carry the heat from the engine cylinder and to keep the temperature of the cylinder in the safe range and extend its life.
6. Lubricating System
It includes oil pumps, oil tanks, filters, coolers and connecting pipes. The function of the lubricating system is to reduce the friction of moving parts and reduce the wear and tear of the engine parts.
7. Starting System
This includes compressed air lanks. The function of this system is to start the engine from the cold by supplying the compressed air.
8. Governing System
This consists of the governor and its function is to maintain the speed of the engine constant irrespective of load on the plant by controlling the fuel supply to the engine according to the load.
Diesel Power Plant Advantages and Disadvantages
Advantages of Diesel Power Plant
Following are the advantages of a diesel power plant:
- Design and installation are very simple.
- Can respond to varying loads without any difficulty.
- The standby losses are less.
- Occupy less space.
- Can be started and put on load quickly.
- No problem with ash handling.
- Requires less quantity of water for cooling purpose.
- Low capital investment
- Requires less operating and maintenance staff.
- More economical lubrication system.
- Can burn a fairly wide range of fuel.
- These plants can be located very nearer to the load centres,
- The cost of the building becomes very low.
- More efficient than the steam power plant.
Disadvantages of Diesel Power Plant
Following are the disadvantages of a diesel power plant:
- High operating cost.
- High maintenance and lubrication cost.
- Diesel units capacity is limited.
- Noise is a serious problem.
- It cannot supply overloads continuously.
- Overload is not possible.
- Releases unwanted emissions.
- Life is quite small (7 to 10 years).
That’s it, thanks for reading. If you like our article on “Diesel Power Plant” please share with your friends. Have any question tell us in the comments.