ICE 4th Year
Bharati Vidyapeeth’s College Of Engineering
Thermal Power Plant
Overview of BHEL
BHEL was established in 1964.
BHEL is one of the only 7 Public Sector Undertakings (PSUs) of India clubbed under the
esteemed 'Maharatna' status. On 1st February 2013, the Government of
India granted Maharatna status to BHEL.
BHEL has a share of 59% in India’s total installed generating capacity contributing 69%
(approx.) to the total power generated from utility sets (excluding non-conventional capacity) as
of March 31, 2012.
BHEL is engaged in the design, engineering, manufacture, construction, testing, commissioning
and servicing of a wide range of products and services for the core sectors of the economy, viz.
Power, Transmission, Industry, Transportation (Railway), Renewable Energy, Oil & Gas and
BHEL has 15 manufacturing divisions, two repair units, four regional offices, eight service centers
and 15 regional centers and currently operate at more than 150 project sites across India and
Installed equipment for over 90000MW of power generation-for utilities, captive and
Supplied over 225000MW a transformer capacity and other equipment operating in
transmission and distribution network up to 400Kv (AC& DC)
Supplied over 25000 motors with drive control system to power projects, petro
chemicals, refineries, steel, aluminium, fertilizers, cement plants etc.
Supplied traction electrics and AC/DC locos to power over 12000kms railway network.
Supplied over one million valves to power plants and other industries.
Main Manufacturing Facilities
Heavy Electrical Plant, Bhopal
Heavy Electrical Equipment Plant, Haridwar (Uttarakhand)
Heavy Power Equipment Plant, Ramachandrapuram, Hyderabad (Andhra Pradesh)
Transformer Plant, BHEL Jhansi (Uttar Pradesh)
High Pressure Boiler Plant and Seamless Steel Tube Plant, Trichy(Tamil Nadu)
Boiler Auxiliaries Plant, Ranipet, Vellore (Tamil Nadu)
Electronics Division and Electro Porcelain Division, Bangalore (Karnataka)
Centralised Stamping Unit & Fabrication Plant(Uttar Pradesh)
Power plant piping unit, Thirumayam (Tamil Nadu)
Power plant fabrication unit, Gondia (under construction)
Insulator Plant Jagdishpur (Uttar Pradesh)
Component Fabrication Plant Rudrapur (Uttrakhand)
Industrial Valves Plant, Goindwal (Punjab)
Bharat Heavy Plates and Vessels Limited (Vizag)
BHEL Electrical Machines Ltd., Kasaragod (Kerala)
Operating Principle: The rotor is mounted
on a shaft driven by mechanical prime
A field winding (rotating ) carries a DC
current to produce a constant magnetic
field. An AC voltage is induced in the 3-
phase stator winding (stationary) to
produce electrical Power.
The electrical frequency of the 3-phase
output depends upon the mechanical speed
and the number of poles.
3-phases output is directly connected to
A steam turbine is a device that
extracts thermal energy from
pressurized steam and uses it to
do mechanical work on a rotating
The steam turbine is a form
of heat engine that derives much
of its improvement in
thermodynamic efficiency from
the use of multiple stages in the
expansion of the steam, which
results in a closer approach to the
ideal reversible expansion process.
The coal is put in the boiler after pulverization. For this pulverizer is used.
A pulverizer is a device for grinding coal for combustion in a furnace in a
Types of Pulverizers:
i)Ball and Tube Mill
ii) Ring and Ball
Boiler is an enclosed vessel in which water is
heated and circulated until the water is
turned in to steam at the required pressure.
Coal is burned inside the combustion
chamber of boiler. The products of
combustion are nothing but gases. These
gases which are at high temperature
vaporize the water inside the boiler to
Boilers are classified as:
1. Fire tube boilers
2. Water tube boilers
Steam after rotating steam turbine comes to condenser. Condenser refers
here to the shell and tube heat exchanger (or surface condenser) installed
at the outlet of every steam turbine in Thermal power stations of utility
The purpose is to condense the outlet (or exhaust) steam from steam
turbine to obtain maximum efficiency and also to get the condensed
steam in the form of pure water, otherwise known as condensate, back to
steam generator or (boiler) as boiler feed water.
Condensers are classified as:
i)Jet condensers or contact condensers,
The condensate (water) formed in the
condenser after condensation is
initially at high temperature. This hot
water is passed to cooling towers.
It is a tower- or building-like device in
which atmospheric air (the heat
receiver) circulates in direct or
indirect contact with warmer water
(the heat source) and the water is
Types Of Cooling Tower-
1. Wet cooling tower
2. Dry cooling tower
Flue gases coming out of the boiler carry
lot of heat. Function of economizer is to
recover some of the heat from the heat
carried away in the flue gases up the
chimney and utilize for heating the feed
water to the boiler.
It is placed in the passage of flue gases in
between the exit from the boiler and the
entry to the chimney.
The use of economizer results in saving
in coal consumption, increase in
steaming rate and high boiler efficiency
but needs extra investment and increase
in maintenance costs and floor area
required for the plant.
It is a device which removes dust or other finely
divided particles from flue gases by charging the
particles inductively with an electric field, then
attracting them to highly charged collector plates.
Some of the usual applications are:
(1) Removal of dirt from flue gases in steam plants
(2) Cleaning of air to remove fungi and bacteria in
establishments producing antibiotics and other
drugs, and in operating rooms
(3) Cleaning of air in ventilation and air
(4) Removal of oil mists in machine shops and acid
mists in chemical process plants
(5) Cleaning of blast furnace gases
(6) Recovery of valuable materials such as oxides of
copper, lead, and tin
An alternator is an electromechanical device that converts mechanical
energy to alternating current electrical energy. Most alternators use a
rotating magnetic field. Different geometries - such as a linear alternator
for use with sterling engines - are also occasionally used. In principle, any
AC generator can be called an alternator, but usually the word refers to
small rotating machines driven by automotive and other internal
It is a device that transfers electric energy from
one alternating-current circuit to one or more
other circuits, either increasing (stepping up) or
reducing (stepping down) the voltage.
Uses for transformers include reducing the line
voltage to operate low-voltage devices (doorbells
or toy electric trains) and raising the voltage from
electric generators so that electric power can be
transmitted over long distances.
Transformers act through electromagnetic
induction; current in the primary coil induces
current in the secondary coil. The secondary
voltage is calculated by multiplying the primary
voltage by the ratio of the number of turns in the
secondary coil to that in the primary.
Stepwise Operation of Thermal Power Plant
1) First the pulverized coal is burnt into the furnace of boiler.
2) High pressure steam is produced in the boiler.
3) This steam is then passed through the super heater, where it further heated up.
4) This supper heated steam is then entered into a turbine at high speed.
5) In turbine this steam force rotates the turbine blades that means here in the
turbine the stored potential energy of the high pressured steam is converted into
6) After rotating the turbine blades, the steam has lost its high pressure, passes
out of turbine blades and enters into a condenser.
7) in the condenser the cold water is circulated with help of pump which
condenses the low pressure wet steam.
8) This condensed water is then further supplied to low pressure water heater
where the low pressure steam increases the temperature of this feed water; it is
then again heated in a high pressure heater where the high pressure of steam is
used for heating.
9) The turbine in thermal power station acts as a prime mover of the alternator.
Efficiency of Thermal Power Station or Plant
The overall efficiency of a thermal power station or plant varies from 20% to 26% and it depends upon plant
Advantages of Thermal Power Plant
They can respond to rapidly changing loads without difficulty
A portion of the steam generated can be used as a process steam in different industries
Steam engines and turbines can work under 25 % of overload continuously
Fuel used is cheaper
Cheaper in production cost in comparison with that of diesel power stations
Disadvantages of Thermal Power Plant
Maintenance and operating costs are high
Long time required for erection and putting into action
A large quantity of water is required
Great difficulty experienced in coal handling
Presence of troubles due to smoke and heat in the plant
Unavailability of good quality coal
Maximum of heat energy lost
Problem of ash removing