---
title: "Hydroelectric schemes by hydraulic characteristics"
subject: "Hydropower Engineering"
chapter: 2
key: "semester_7/hydropower_engineering:hydroelectric-scheme-types-hydraulic"
source: https://www.bctengineer.com/q/semester_7/hydropower_engineering/hydroelectric-scheme-types-hydraulic
site: BCT Engineering
---

# Hydroelectric schemes by hydraulic characteristics

Hydropower Engineering · Chapter 2: Planning of Hydropower Projects

- Asked in: 2076 Chaitra, 4 marks
- Video: [Types of hydro power plants, Classification of Hydro power plants, #HydroPlant](https://www.youtube.com/watch?v=2Ya1i7oQphg) — Mechanical Engineering Management
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_7/hydropower_engineering/hydroelectric-scheme-types-hydraulic
- Whole chapter: https://www.bctengineer.com/md/semester_7/hydropower_engineering/chapter-2

## Question

Describe various types of hydroelectric schemes based on hydraulic characteristics.

## Short answer

Run-of-river (RoR) uses river flow directly with daily pondage for peaking; storage uses a dam reservoir for firm year-round power; diversion conveys water via canal/tunnel to a downstream powerhouse to gain head; dam-toe places powerhouse at dam foot; pumped storage uses two reservoirs for peak/off-peak; tidal is unsuitable for Nepal.

## Answer

Based on hydraulic characteristics (how water is brought to the turbine), hydropower schemes are:

#### 1. Run-of-river (RoR) scheme
- Uses river flow directly without significant storage; a small weir diverts the water. Output follows the river flow.
- Variants: RoR with daily pondage (peaking RoR).

#### 2. Storage (reservoir) scheme
- A dam stores monsoon flow and releases it as needed. Gives firm power and can regulate the river seasonally or annually.

#### 3. Diversion (canal/tunnel) scheme
- Water is diverted from a weir by a canal or tunnel along the river to a powerhouse downstream, so that the head is gained over the length of the river.
- Types: free-flow canal, pressure tunnel.

#### 4. Dam-toe (dam-based) scheme
- Powerhouse is at the foot of the dam, and the head comes from the dam height.

#### 5. Pumped storage scheme
- Two reservoirs; water is pumped up in off-peak time and used in peak time.

#### 6. Tidal scheme (also considered)
- Uses the rise and fall of the sea; not suited for Nepal.

```text
 Diversion RoR          Storage dam-toe
 weir--canal--forebay   reservoir | dam
              | penstock          |__ PH
              PH
```

## Check yourself

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

1. What is a run-of-river scheme?
   A. Large reservoir
   B. Uses tide
   C. Two reservoirs
   D. Uses river flow directly without significant storage
   Answer: D. Output follows river flow. (Key point: RoR)

2. Where is the powerhouse in a dam-toe scheme?
   A. Far downstream
   B. At the foot of the dam
   C. Underground at source
   D. At the intake
   Answer: B. Head comes from dam height. (Key point: Dam-toe)

## Related in Hydropower Engineering

- [Types of hydropower plants by head, turbine, load](https://www.bctengineer.com/question.md?key=semester_7%2Fhydropower_engineering%3Ahydropower-plant-types-classification) — Hydropower Engineering, chapter 2

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