---
title: "Captive power generation and its needs"
subject: "Power Plant Design"
chapter: 1
key: "semester_8/power_plant_design:captive-power-generation"
source: https://www.bctengineer.com/q/semester_8/power_plant_design/captive-power-generation
site: BCT Engineering
---

# Captive power generation and its needs

Power Plant Design · Chapter 1: Energy Sources and Electric Power Generation

- Asked in: 2081 Chaitra, 4 marks; 2080 Chaitra, 4 marks; 2074 Magh, 4 marks (asked 3 times)
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_8/power_plant_design/captive-power-generation
- Whole chapter: https://www.bctengineer.com/md/semester_8/power_plant_design/chapter-1

## Question

What do you mean by captive power generation? Discuss its needs.

## Short answer

Captive power is a plant set up by an industry for own use, with surplus possibly sold to grid. Needs arise from unreliable grid, power quality, remote locations, use of by-products (bagasse, waste heat), cost savings, and emergency backup.

## Answer

**Captive power generation** means a power plant set up by an industry or institution mainly for its **own use**, not primarily to sell to the public grid. Examples: diesel generator sets in factories, a sugar mill's bagasse-fired plant, a cement plant's waste-heat plant, or a hospital's standby generator. Surplus power may be sold to the grid under an agreement.

#### Needs of captive power generation
1. **Unreliable grid supply** – load shedding, outages and voltage dips stop production; industries need continuous power (Nepal faced long load shedding until about 2017).
2. **Power quality** – sensitive processes (cement, steel, pharmaceuticals, data centres, hospitals) need stable voltage and frequency.
3. **Remote locations** – mines, hydropower construction sites, telecom towers and hotels far from the grid.
4. **Use of by-products** – bagasse, rice husk, waste heat or process gas can be turned into power cheaply (often as cogeneration).
5. **Cost saving** – where grid tariff or demand charge is high, own generation can reduce cost.
6. **Standby and emergency** – hospitals, airports, banks need backup for critical loads.
7. **Grid capacity limits** – new large loads where transmission or substation capacity is not yet available.

#### Points to consider
| Aspect | Remark |
|---|---|
| Fuel | Diesel is costly and imported in Nepal |
| Size | Usually a few kW to tens of MW |
| Grid tie | Needs synchronising and protection |
| Environment | Emissions and noise from diesel units |

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. What is a captive power plant?
   A. A plant owned by the utility to supply the public grid
   B. A plant set up by an industry or institution mainly for its own use
   C. A plant that only sells power abroad
   D. A plant that has no generator
   Answer: B. Captive plants serve the owner's own load; surplus may be sold to the grid by agreement. (Key point: Meaning of captive power)

2. Which is a main reason industries set up captive generation?
   A. Load shedding, outages and voltage dips that stop production
   B. Grid supply is always perfect
   C. To avoid using by-products
   D. To remove the need for standby power
   Answer: A. Unreliable supply and poor power quality stop continuous processes, so industries generate their own power. (Key point: Need: unreliable grid)

3. How can a sugar mill's by-product be a need for captive generation?
   A. Bagasse is burnt in a boiler to give steam and power cheaply
   B. Bagasse is thrown away
   C. Bagasse is used only as fertiliser
   D. Bagasse replaces the grid transformer
   Answer: A. By-products such as bagasse, rice husk or waste heat give cheap power, often as cogeneration. (Key point: Use of by-products)

## Related in Power Plant Design

- [Energy sources and solar power generation](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Aenergy-sources-solar-power) — Power Plant Design, chapter 1
- [Solar generation and wind power characteristics](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Asolar-generation-wind-characteristics) — Power Plant Design, chapter 1
- [Tidal power generation and output: 3 km × 3 km](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Atidal-generation-3x3km) — Power Plant Design, chapter 1
- [Generation expansion planning and load forecasting](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Ageneration-expansion-load-forecast) — Power Plant Design, chapter 2
- [Generation expansion planning procedure](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Ageneration-expansion-procedure) — Power Plant Design, chapter 2, asked 3×
- [Nepal generation and consumption trends](https://www.bctengineer.com/question.md?key=semester_8%2Fpower_plant_design%3Anepal-generation-trend-5-years) — Power Plant Design, chapter 1

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