Hydel power plant , construction

Hydel power plant 

Type of hydel power plant 

According water storage 

1. Run-off river plant without poundage
2. Run of  river plant with poundage
3. Reservoir plants

According to Head they are classified in three parts 

1. Low head plant
2. medium head plant
3. High head plant

1. Low head plant

In such type of plant no storage tank is required. In such plant Francis, propeller the water head available less than 30m. The production of electricity will be less by using this plant. 

2.  Medium head plant 

In this plant mainly water is through main reservoir to for bay and then to the pen stock
The fore bay acts as surge tank for these plants
Medium head plant use Francis type turbine

3. High head plant 

This plant works above 500m and used pelton wheel turbines are commonly used. In this plant water is carried out from the main reservoir by a tunnel up to surge tank and then from then from the surge tank to the power house in pen stock.

According to load 

1. Base load plants
2. Peak load plants

1. Base load power plant 

These plants are depending on the nature of load if demand is more , this plant are used regularly . and load reactor of this plants are high.

2. Peak load plant 

these plant are mainly used during the peak load . Run of river plants with poundage can be used as peak load plants.

Pumped Storage plants 

these plant are used when quantity of water available for generation is in suffice . If it is possible to pond at head water and tail water location after passing threw the turbine is stored in the tail race pond from it may be pumped back to the head water pond.  

Component  of Hydel power plant 

 1. Fore bay 

It is enlarged body of water provided in front of pen-stock . it is provided in case of run of river plant and storage plant. main function of fore bay is to store water and supplied it dueling generation of electrical power.

2. In tack structure 

In tack  structure can be classified as high-presser in tack and low pressure in tack . high pressure in tack are used in case of big storage reservoir and low presser in-tack is used for small ponds to store small quantity of water for daily or weakly load variation.

3. Pen stock 

in hydel power plant open or closed conduced are used to carry the water to the turbines . it is made of reinforced  steal. concrete pen-stock are suitable for low heads less ha 30m . and steel pen stock are designed for any head.  thickness of pen stock increases with head or water presser.

4. Surge tank 

As the load on the turbine deceases or during load tank provides space for holding water when the governor opens the turbine gate suddenly to admit more water, there is a tendency to cause a vacuum in the pen stock.

5. Turbines 

Turbines are use to convert the energy of flowing water into mechanical energy .
Water turbine is a rotary ending that takes energy from moving water .

Types of turbine 

1. Impulse turbine
2. Reaction turbine

6. Draft tube 

It reduced high velocity of water discharge by the turbine . draft tube permit turbine to be install at higher level than tail race level which help maintenance and repair turbines.

7. Tail race 

Tail race is designed such a rays heat water hammer is minimize when water leave the draft tube .

8. Power house 

Generator
which convert mechanical energy into electrical energy
Excitation system
Governed
Step up transformer
High voltage switch
DC system
Switch yard
Main inlet
So finaly these component needed in hydel power plant