Lesson 4 - Hydro power.pptx energy technologies

energy technology

1. Module : energy technologies Lesson 4 : Hydro power generation

2. Outline History Types of plants Component of a plant Types of turbines Calculation of power Environmental impacts Comparison with other sources

3. History Used before 4000 years to generate mechanical power Electrical power generation in 18 th /19 th century Sri Lanka At early 20 th century in plantation sector Laxapana (1950) Mahaweli (1970s) Small hydro (1996 onwards)

4. Type of plants Reservoir type / Run-off river type Grid connected / Stand alone High head / Low head Pumped Hydro

5. Components of a plant Weir / Intake Headrace channel / pipe Desilting tank Forebay tank / Valve house Penstock & supports Power house (Turbine) Tail race

6. Schematic diagram of a hydro plant

7. Turbine types Impulse type Pelton wheel Turgo impulse Cross flow Reaction type Francis Kaplan

8. Turbine selection

9. Calculation of power Rain fall Catchment area Hydrology / Design flow Gross head Pipe loss Net head Input power to the turbine Efficiency of turbine / generator

10. Features of hydro power Renewable / Environmental friendly Seasonal variations of energy supply Storage possible in large projects Convenient start / shut down Can be merged with other projects (e.g. irrigation) Essential operation due to up/down stream requirements

11. Environmental impacts During construction Loss of vegetation Sound Dust During operation Dewatering in the stream