Blog on hydro power plant (Part 2- Working of plant and parts)

Blog on hydro power plant (Part 2- Working of plant and parts)

 WATCH THE ABOVE VIDEO FOR BETTER                   UNDERSTANDING

 

 

1) Dam

The dam is the most important component of hydroelectric power plant. The dam is built on a large river that has abundant quantity of water throughout the year. It should be built at a location where the height of the river is sufficient to get the maximum possible potential energy from water.

2) Water Reservoir

The water reservoir is the place behind the dam where water is stored. The water in the reservoir is located higher than the rest of the dam structure. The height of water in the reservoir decides how much potential energy the water possesses. The higher the height of water, the more its potential energy. The high position of water in the reservoir also enables it to move downwards effortlessly.

The height of water in the reservoir is higher than the natural height of water flowing in the river, so it is considered to have an altered equilibrium. This also helps to increase the overall potential energy of water, which helps ultimately produce more electricity in the power generation unit.

3) Intake or Control Gates

These are the gates built on the inside of the dam. The water from reservoir is released and controlled through these gates. These are called inlet gates because water enters the power generation unit through these gates. When the control gates are opened the water flows due to gravity through the penstock and towards the turbines. The water flowing through the gates possesses potential as well as kinetic energy.

4) The Penstock

The penstock is the long pipe or the shaft that carries the water flowing from the reservoir towards the power generation unit, comprised of the turbines and generator. The water in the penstock possesses kinetic energy due to its motion and potential energy due to its height.

The total amount of power generated in the hydroelectric power plant depends on the height of the water reservoir and the amount of water flowing through the penstock. The amount of water flowing through the penstock is controlled by the control gates.

5) Water Turbines

Water flowing from the penstock is allowed to enter the power generation unit, which houses the turbine and the generator. When water falls on the blades of the turbine the kinetic and potential energy of water is converted into the rotational motion of the blades of the turbine. The rotating blades causes the shaft of the turbine to also rotate. The turbine shaft is enclosed inside the generator. In most hydroelectric power plants there is more than one power generation unit.

There is large difference in height between the level of turbine and level of water in the reservoir. This difference in height, also known as the head of water, decides the total amount of power that can be generated in the hydroelectric power plant.

There are various types of water turbines such as Kaplan turbine, Francis turbine, Pelton wheels etc. The type of turbine used in the hydroelectric power plant depends on the height of the reservoir, quantity of water and the total power generation capacity.

6) Generators

It is in the generator where the electricity is produced. The shaft of the water turbine rotates in the generator, which produces alternating current in the coils of the generator. It is the rotation of the shaft inside the generator that produces magnetic field which is converted into electricity by electromagnetic field induction. Hence the rotation of the shaft of the turbine is crucial for the production of electricity and this is achieved by the kinetic and potential energy of water. Thus in hydroelectricity power plants potential energy of water is converted into electricity.

 

Blog on hydro power plant (Part 1- Selection of site and introduction)

PART 1- Selection of site and introduction

PART 2- Working of plant and parts

 

Blog on hydro power plant (Part 1- Selection of site and introduction)

While selecting a suitable site for a hydro-electric power plant, if a good system of natural storage-lakes at high altitudes and with large catchment areas can be located, the plant will be comparatively economical.

Anyhow the essential characteristics of a good site are:

      1. large catchment area, 

      2.high average rain fall and

  3.favorable place for constructing the storage or reservoir.

   4. The land should be cheap in cost and rocky in order to withstand the weight of large building and heavy machinery.

  5.    There should be possibility of providing adequate transportation facilities so that the necessary equipment and machinery could be easily transported.

INTRODUCTION

Power system mainly contains three parts namely generation, transmission and distribution. Generation means how to generate electricity from the available source and there are various methods to generate electricity but in this article we only focused on generation of electricity by the means of hydro or water (hydro power plant). As we know that the power plant is defined as the place where power is generated from a given source, so here the source is hydro that’s why we called it hydro power plant .

 In hydro power plant we use gravitational force of fluid water to run the turbine which is coupled with electric generator to produce electricity. This power plant plays an important role to protect our fossil fuel which is limited, because the generated electricity in hydro power station is the use of water which is renewable source of energy and available in lots of amount without any cost. The big advantage of hydro power is the water which the main stuff to produce electricity in hydro power plant is free, it not contain any type of pollution and after generated electricity the price of electricity is average not too much high.

IN PART 2 THERE IS EXPLANATION AND VIDEO TO UNDERSTAND 

 

FROM   ...ABDUR REHMAN CHHAPRA...

Blog on gas turbine power plant (Part 2- working of plant and parts )

Blog on gas turbine power plant (Part 2- working of plant and parts )

 

 VIDEO 1

                                        VIDEO 2

SEE BOTH THE VIDEOS FOR BETTER EXPLANATION

Gas turbine functions in the same way as the Internal Combustion engine. It sucks in air from the atmosphere, compresses it. The fuel is injected and ignited. The gases expand doing work and finally exhausts outside. The only difference is instead of the reciprocating motion, gas turbine uses a rotary motion throughout.

                     

This article will explain the three main sections of the Gas Turbine.

1. Compressor.

The compressor sucks in air form the atmosphere and compresses it to pressures in the range of 15 to 20 bar. The compressor consists of a number of rows of blades mounted on a shaft. This is something like a series of fans placed one after the other. The pressurized air from the first row is further pressurised in the second row and so on. Stationary vanes between each of the blade rows guide the air flow from one section to the next section. The shaft is connected and rotates along with the main gas turbine.

2. Combustor.

This is an annular chamber where the fuel burns and is similar to the furnace in a boiler. The air from the compressor is the Combustion air. Burners arranged circumferentially on the annular chamber control the fuel entry to the chamber. The hot gases in the range of 1400 to 1500 °C leave the chamber with high energy levels. The chamber and the subsequent sections are made of special alloys and designs that can withstand this high temperature.

 

3. Turbine

The turbine does the main work of energy conversion. The turbine portion also consists of rows of blades fixed to the shaft. Stationary guide vanes direct the gases to the next set of blades. The kinetic energy of the hot gases impacting on the blades rotates the blades and the shaft. The blades and vanes are made of special alloys and designs that can withstand the very high temperature gas. The exhaust gases then exit to exhaust system through the diffuser. The gas temperature leaving the Turbine is in the range of 500 to 550 °C.

The gas turbine shaft connects to the generator to produce electric power. This is similar to generators used in conventional thermal power plants.

  Performance

More than Fifty percent of the energy converted is used by the compressor. Only around 35 % of the energy input is available for electric power generation in the generator. The rest of the energy is lost as heat of the exhaust gases to the atmosphere.

Three parameters that affect the performance of a of gas turbine are

     1.    The pressure of the air leaving the compressor.

     2.    The hot gas temperature leaving the Combustion chamber.

     3.    The gas temperature of the exhaust gases leaving the turbine.

The above is a simple description of the Gas Turbine. Actually it is a very sophisticated and complex equipment which over the years have become one of the most reliable mechanical equipment.

FROM ...ABDUR REHMAN CHHAPRA...