--- title: "Layout of diesel power plant" subject: "Power Plant Equipment" chapter: 5 key: "semester_7/power_plant_equipment:diesel-plant-layout" source: https://www.bctengineer.com/q/semester_7/power_plant_equipment/diesel-plant-layout site: BCT Engineering --- # Layout of diesel power plant Power Plant Equipment · Chapter 5: Diesel Power Plant - Asked in: 2079 Bhadra, 8 marks; 2071 Chaitra, 4+4 marks; 2074 Chaitra, 6 marks (asked 3 times) - Video: [Diesel Power Plant || working and layout || Diesel Engine](https://www.youtube.com/watch?v=ly9CI9nXaC8) — Aeran Classes - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_7/power_plant_equipment/diesel-plant-layout - Whole chapter: https://www.bctengineer.com/md/semester_7/power_plant_equipment/chapter-5 ## Question Draw a complete sketch of a diesel power plant and mention its different systems. ## Short answer A diesel plant has an engine coupled to an alternator plus fuel supply, air intake, exhaust, cooling, lubrication, starting, governing, and electrical systems. These systems together store and burn fuel, remove heat and exhaust, and maintain generator output. ## Answer A **diesel power plant** is a generating station in which a diesel (compression-ignition) engine is the prime mover driving an alternator. It is used for standby, peak load and small isolated loads. #### Schematic of a diesel power plant ```text Air filter -> Intake Exhaust -> Silencer -> Stack | ^ Fuel tank +----v----------+----+ coupling +-----+ -> filter->| DIESEL ENGINE |============| Alt |->Bus -> pump -> | (injectors) | +-----+ -> injector+--+-----------+-----+ | | | Exciter Cooling water Lube oil pump <-> cooling pump <-> oil tower/radiator cooler, filter Starting: compressed air bottles / electric motor ``` #### Systems of a diesel power plant **1. Engine and alternator:** the diesel engine (2- or 4-stroke) converts the chemical energy of fuel into mechanical work; it is coupled to an alternator with its exciter on a common bed plate. **2. Fuel supply system:** storage tank → transfer pump → day tank → filters → fuel (booster) pump → fuel injection pump → injectors. It stores, cleans and injects the correct quantity of fuel at high pressure at the right time. **3. Air intake system:** air filter, intake ducts and (often) a turbo-charger/supercharger with intercooler. It supplies clean air for combustion. **4. Exhaust system:** exhaust manifold, silencer (muffler) and chimney. It removes exhaust gases and reduces noise; exhaust heat may be recovered in a waste-heat boiler or to heat oil/water. **5. Cooling system:** water pump, jacket, heat exchanger, radiator or cooling tower. It removes about 30 % of fuel heat to keep cylinder, piston and valves within safe temperature. **6. Lubrication system:** oil sump, pump, filter and oil cooler. It reduces friction and wear and also cools pistons and bearings. **7. Starting system:** compressed-air bottles with compressor (large engines), electric starter motor with battery (small engines), or an auxiliary petrol engine. The engine cannot start by itself. **8. Governing system:** governor that changes the fuel supply to keep speed (frequency) constant as load varies. **9. Electrical system:** alternator, exciter, switchgear, protection, and control panel. ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. What is the role of the diesel engine in a diesel power plant? A. It is the prime mover, converting fuel energy into mechanical work to drive the alternator B. It generates electricity directly C. It only provides starting air D. It cools the alternator Answer: A. The compression-ignition engine is coupled to an alternator, which produces the electrical output. (Key point: Role of the diesel engine) 2. Which order of the fuel supply system is correct? A. Injector - injection pump - day tank - storage tank B. Storage tank - transfer pump - day tank - filters - booster pump - injection pump - injectors C. Day tank - storage tank - injectors - booster pump D. Injection pump - filter - storage tank - injector Answer: B. Fuel is stored, transferred, cleaned, pressurised and then injected into the cylinders. (Key point: Fuel supply path) 3. Why does a diesel plant need a starting system? A. The engine cannot start by itself, so air bottles, a starter motor or an auxiliary engine crank it B. To cool the exhaust C. To clean the fuel D. To regulate frequency Answer: A. A diesel engine must be turned initially to build compression; compressed air or an electric starter does this. (Key point: Why a starting system is needed) 4. What does the governing system do? A. Changes fuel supply to keep speed (frequency) constant as load varies B. Silences the exhaust C. Cools the lubricating oil D. Filters intake air Answer: A. The governor adjusts the fuel injected so engine speed, hence frequency, stays constant. (Key point: Function of governor) ## Related in Power Plant Equipment - [Diesel layout with its five systems](https://www.bctengineer.com/question.md?key=semester_7%2Fpower_plant_equipment%3Adiesel-layout-five-systems) — Power Plant Equipment, chapter 5 - [Diesel layout, starting and fuel supply systems](https://www.bctengineer.com/question.md?key=semester_7%2Fpower_plant_equipment%3Adiesel-layout-starting-fuel) — Power Plant Equipment, chapter 5 - [Diesel plant lubrication and cooling systems](https://www.bctengineer.com/question.md?key=semester_7%2Fpower_plant_equipment%3Adiesel-lubrication-cooling) — Power Plant Equipment, chapter 5, asked 2× - [Fuel supply system of diesel plant](https://www.bctengineer.com/question.md?key=semester_7%2Fpower_plant_equipment%3Adiesel-fuel-supply) — Power Plant Equipment, chapter 5, asked 3× - [Diesel plant components and fuel supply](https://www.bctengineer.com/question.md?key=semester_7%2Fpower_plant_equipment%3Adiesel-components-fuel-supply) — Power Plant Equipment, chapter 5, asked 3× - [Advantages and disadvantages of diesel plant](https://www.bctengineer.com/question.md?key=semester_7%2Fpower_plant_equipment%3Adiesel-plant-merits-demerits) — Power Plant Equipment, chapter 5 ## Related in other subjects - [Load duration curve; diesel plant; ROR flow duration](https://www.bctengineer.com/question.md?key=semester_7%2Fhydropower_engineering%3Aload-duration-diesel-import-fdc) — Hydropower Engineering, chapter 3 - [Development cycle; storage plant layout](https://www.bctengineer.com/question.md?key=semester_7%2Fhydropower_engineering%3Adev-cycle-storage-layout) — Hydropower Engineering, chapter 2 - [Flow patterns in plant layout](https://www.bctengineer.com/question.md?key=semester_6%2Findustrial_engineering_and_management%3Aflow-patterns-in-production-layout) — Industrial Engineering and Management, chapter 2 - [Auxiliary systems of a 100 MW Francis plant](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Aauxiliary-ancillary-systems) — Power Plant Design, chapter 4