Showing posts with label Power Generation. Show all posts
Showing posts with label Power Generation. Show all posts

Site Selection of Hydroelectric Power Stations

Factors Affecting Hydroelectric Plant Location

Site selection of Hydroelectric  power plant

Hydroelectric power / Hydro-power plant is one of the eco-friendly power generation systems.It has less running cost and high efficiency (around 50%, compared to thermal plant much better). Site selection of hydroelectric power plant depends on some factors in order to give efficient output in terms of overall performance and economic.

Site selection of Hydroelectric power plant. 
Choice of Site For Hydro-Electric Power Stations

What are the points to be considered while selecting the sites of hydroelectric power plant?

The following points should be taken into account while selecting the site for a hydro-electric power station : 

(i) Availability of water.

Since the primary requirement of a hydro-electric power station is the availability of huge quantity of water,  such plants should be built at a place (e.g., river, canal) where adequate water is available at a good head.

(ii) Storage of water.

There are wide variations in water supply from a river or canal during the year.  This makes it necessary to store water by constructing a dam in order to ensure the generation of power throughout the year.  The storage helps in equalizing the flow of water so that any excess quantity of water at a certain period of the year can be made available during times of very low flow in the river.   This leads to the conclusion that site selected for a hydro-electric plant should provide adequate facilities for erecting a dam and storage of water.

(iii) Cost and type of land.

The land for the construction of the plant should be available at a reasonable price.  Further, the bearing capacity of the ground should be adequate to withstand the weight of heavy equipment to be installed.

(iv) Transportation facilities.

The site selected for a hydro-electric plant should be accessible by rail and road so that necessary equipment and machinery could be easily transported. It is clear from the above mentioned factors that ideal choice of site for such a plant is near a river in hilly areas where dam can be conveniently built and large reservoirs can be obtained.

how to select site for hydroelectric power plant ?
site selection of hydroelectric power plant
steps to site selection of hydroelectric power plant
selection of site for thermal power plant

Generation of electrical energy


Energy exists in different forms in nature but the most important form is the electrical energy.Now a days usage of electricity is very high it has become a basic need for everyone. 

Why electrical energy why not other energy sources?

Well, the simple answer to this is the modern technology has developed in such a way that electrical energy can be easily converted into all other energy forms. It also has other advantages  as mentioned below.

1.Greater flexibility: As it can be easily transported with the help of conductors from one place to other it has great flexibility.

2.Convenient : As it can be easily converted into other forms of energy it is very convenient form.  If we take the example of converting electrical energy into heat energy  all we need to do is just pass electricity through a resistor then electrical energy converts o heat energy. Similarly, all the others forms of energy like light,mechanical etc can be obtained easily from electrical energy.

3.Cheapness: When compared to other forms of energy electrical energy is much cheaper . Thus it is  economical to use for any purpose.

4.Cleanliness: Electrical energy doesn't produce  smoke,ash or poisonous  gases. So it maintains cleanliness.

5.Easy control: The electrically operated machines can be controlled easily by switching on or off the switch. For example we can turn off or on the fan by switching off or switching on the switch. And speed can also be easily controlled for example speed of fan can be adjusted by using a regulator. So it is easy to control.

6.High transmission efficiency:  Consumers of electrical energy are located away from the electricity generation stations generally.But with the help of over head line conductors and by using transformers and few other equipment's electricity can be supplied efficiently with less amount of losses.

The above mentioned advantages made usage of electrical energy popular than other energy forms.

Generation of electrical energy:

Converting  different forms of energy that are present in nature into electrical energy is known as generation of electrical energy.

To get the basic idea of generation of electrical energy observe the following figure. 

Energy from any of the sources like heat, wind, hydro, fossil etc can be given as input to the prime mover. For example take hydro energy, Water at certain head  when falls on the prime mover which is a rotating part rotates the prime mover in this way the potential energy exerted on it is converted to mechanical energy. This prime mover drives generator and the generator converts mechanical energy to electrical energy.

Sources of energy:

1. Fuels: Fuels like  coal,  oil and natural gas are the main sources of energy. The heat energy produced  by these fuels is converted into mechanical energy by certain type of  prime movers like steam engines, steam turbines etc. The prime mover drives the alternator which converts mechanical energy into electrical energy. Although these fuels play main role in the electrical energy production now a days we need to see other alternatives as there quantity is diminishing due to increase in the usage of electrical energy. The alternative to them is renewable energy sources likes solar, wind, hydel.

2.Solar energy:  Sun is the major source of energy. Electrical energy can be produced from sun by focusing the heat energy produced  by sun on reflectors and heating water which produces steam which in turn rotates the turbine which is coupled to the generator and this generator converts mechanical energy to electrical energy. As it has limitations like availability of solar energy is not possible all the time it can be used as alternative wherever other sources of energy are not available abundantly.

3.Water:  When water present at certain head falls down on turbine the potential energy possessed by water is converted into mechanical energy by a water turbine. This turbine drives the generator which converts mechanical energy to electrical energy.

4. Wind: To generate electrical energy from wind energy a wind mill is established. This runs the generator which produces electrical energy. Wind mills are generally placed at hilly areas.It is cheaper way to generate electrical energy.

5.Nuclear energy: Very large amount of heat can produced by nuclear fuels like uranium. This heat energy is utilized to produce steam. This stem rotates the steam turbine and runs the generator which can produce electrical energy.

This helps you to understand the basics of generation of electrical energy from different power plants.  


Some energy is lost i.e converted to other form of energy other than electrical energy  while converting any input energy to output electrical energy. Efficiency gives you how efficiently the input energy given is converted to output electrical energy. Efficiency is generally calculated in percentage.

Efficiency of power plant =  output energy / input energy = output power / input power.
Power is rate of flow of energy.

In this post we have learnt about electrical energy importance and generation of electrical energy from different power plants.

To download this post on generation of electrical energy as PDF click here


Thermal Power Plant Advantages & Disadvantages

The steam or thermal power plants have the following advantages and disadvantages over plants

Advantages and Disadvantages of Thermal Power Plants

Advantages of Thermal Power Plant

1. Cheaper in production cost when compared with that of diesel power plant.
2. This plant can be installed at any place irrespective of the existence of fuels.Where as hydroelectric plant is install only at the source of water power areas. 
3. These plants can be located near the load centers.
4. It requires less space compared to the hydro electric power station.
5. In this system, fuel used is cheaper.
6. Steam engines and turbines can run under 25% of overload continuously.
7. A portion of steam raised can be used as process steam in various industries.

Read : Thermal Power Station Operation

Disadvantages of Thermal Power Plant 

1. Maintenance and operating costs are high. 
2.Pollution is a major problem due to fumes and residues from pulverized fuels.
3. Handling of coal and disposal of ash is quite difficult.
4. Troubles from smoke and heat from the plant.
5. The plant cost increases due to increase in operating temperature and pressure.
6. Huge quantity of water is required.
7. Efficiency falls rapidly below 75% at full load.