The document discusses India's power system structure and conventional power sources. It notes that power is primarily owned by state electricity boards and generated through thermal, hydroelectric, nuclear and renewable sources. Thermal power makes up the largest portion at 65% of total installed capacity, with coal being the primary fuel. Key components and processes of thermal, hydroelectric and nuclear power plants are described. Other conventional power sources like gas turbines and diesel engines are also briefly outlined.

1. GENERATION
CONVENTIONAL SOURCES
STRUCTURE OF POWER SYSTEM
 Power system owned by state electricity boards.
 Private sector utilities operate in Mumbai, Kolkata, Ahmedabad
 Regional electricity boards – Northern, Southern, Eastern, Western, North-eastern.
 Power Grid corporation- Central.
Introduction
 India is one of the world’s largest consumer of energy
 Installed capacity – 1,67,317 MW
 Thermal = 1,08,602 MW
 Nuclear = 4,780 MW
 Hydro = 37,367 MW
 RES = 16,787 MW
 Per capita power consumption – 612KWH
 Annual power production – 680 billion KWH

2. Break up of Power
 Thermal power Plants : 65.34%[
 Hydro Electric Power Plants : 21.53%
 Nuclear Power Plants : 2.70%
 Renewable energy sources : 10.42%
 30% to 40% of electrical power is lost in transmission and distribution
Thermal Power Plants
 Installed Capacity – 65% of total installed capacity.
 Coal based –54% of total installed capacity.
 Gas Based –10% of total installed capacity.
 Oil Based –1% of total installed capacity.
Main Components
 Fuel Handling Unit
 Ash Handling Unit
 Boiler Unit
 Feed Water Unit
 Cooling Water Unit
 Generator Unit

3.  Turbine Unit
Main Circuit
 Fuel And Ash Circuit
 Air And Gas Circuit
 Feed Water And Steam Circuit
 Cooling Water Circuit
Fuel And Ash Circuit
 Fuel stored and fed to the boiler through conveyor belts. Broken down into proper shape
for complete burning.
 Ash thus generated after burning is removed from the boiler through ash handling
equipment
Air And Gas Circuit
 Air is required for combustion of fuel and is supplied through fans
 Air is passed through air preheater to extract energy from flue gases for proper burning of
the fuel
 Flue gases have ash and several gases which are passed through the precipitator(dust
collector) and go to atmosphere through chimney.
Feed Water And Steam Circuit
 Steam Converted to water by condenser.
 Water is demineralized & hence not wasted to have better economic operation of the
plant.
 Some part of steam and water is lost while passing through different parts.
 Boiler feed pump feeds water into the boiler drum where it is heated to form steam.
 Wet steam is again heated in super heater before passing through the turbine
 Steam is expanded in the turbine to run it. After which again it goes to boiler for
reheating
Cooling Water Circuit
 To condensate the steam, large quantity of cooling water is required which is taken from
river or pondage
 After passing through the condenser, it is fed back to the river or Pondage

4. Boiler
Turbine
Economizer

5. Selection Of site
 Availability of cheap land.
 Availability of water.
 Availability of fuel.
 Possibility of future expansion of the plant.
 Away from the urban areas due to pollution.
 The initial cost of plant.
 Magnitude and nature of load to be handled.
Hydro Power Plant
 India is Pioneer in HEP
 Darjeeling(1898) and Shivanasamudra (1902) one of the first in Asia.
 Installed Capacity – 37,367MW

6. Advantages of Hydro Power Plant
 Water is self – replenishing, non wasting.
 Water reaches the powerhouse site on its own.
 Water after producing electricity can be used for drinking or irrigation.
 Efficiency of HEP is high(about 80%).
 HEP has very long life.
 Maintenance is easy and less expensive.
 The percentage outage is low.
 Benefits of recreation, fisheries etc.
Selection of sites
 Availability of water
 Storage of water
 Head of water
 Distance of power station to the load centres
 Accessibility of site

7. Classification of HEP based on Capacity
 Very low-capacity plants – up to 0.1MW
 Low capacity plants – up to 1.0 MW
 Medium-capacity plants – up to 10 MW
 High-capacity plants – more than 10 MW
Classification of HEP based on Capacity
 Micro Hydro plants : < 100KW
 Mini Hydro plants : 100KW to 1MW
 Small Hydro plants : 1MW to few MW
 Hydro plants : More than a few MW
 Super Hydro plants : More than 1000MW
Classification of HEP based on Head
 Low-head Plants < 15m
 Medium-head Plants 15 – 70m
 High-head Plants 71 – 250m
 Very High-head Plants > 250m
Nuclear Power Plants
 Twenty Nuclear Reactors
 Production – 4780 MW
 Energy from atomic nuclei via controlled nuclear reactions(Fission)
 Uranium-235 and plutonium-239.
Nuclear Fission

8. NPP Using A Heat Exchanger
PWR – Pressurized Water Reactor(Nuclear Furnace or Pile)
Main Components Of A Reactor
 Fuel Rods – Tube filled with pellets of Uranium
 Shielding - Protection against alpha, beta and Gamma Rays
 Moderator - Slow down the neutron release(Heavy water, Beryllium, Graphite)
 Control Rods - neutron absorbing material(boron Carbide, cadmium)
 Coolant - To transfer the heat generated inside the reactor to a heat exchanger for
utilization of power generation(CO2, H2, He, heavy water, liquid metal-Sodium or
Potassium)
 Steam Separator - steam from the heated coolant is fed to the turbines to produce
electricity from generator.

9.  Containment - concrete lined cavity acting as a radiation shield
Boiling Water Reactor (BWR)
Heavy Water Reactor(CANDU)
Gas-Cooled Reactor

10. Selection of Site
 Availability of water - NPP requires ample amount of water for cooling and steam
generation.
 Disposal of Waste – Dangerous waste/residue obtained
It needs to be disposed deep under the ground in sea so that radioactive effect is
eliminated.
 Away from populated area – For health safety
 Nearest to the load centre
 Other Factors – Accessibility to the road and rail are general considerations.
Advantages of NPP
 Fuel is easy to transport.
 Energy generated is very efficient and the remaining waste is compact.
 Nuclear reactors need little fuel.
 Amount of waste produced is much smaller than that produced in coal burning plant
 Chance of a nuclear accident is 1 in 250 years.
 Clean source of energy.
Disadvantages
 Actual cost of producing energy is more because of containment, radioactive waste
storage system
 The mining of the fuel itself can cause serious problems
 The meltdown of reactor can cause serious disaster.
GAS POWER PLANT

11. Axial Compressor
 Air is taken from the atmosphere , compressed, heated (usually by combustion of fuel in
the air) and expanded in the turbine.
 Gases coming out of the turbine are exhausted in the air.
 Used in emergency and when there is peak demand.
 Fossil fuels such as gasoline, natural gas etc are used as fuel
Diesel Engine
 It is an internal combustion engine that uses the heat of compression to initiate ignition to
burn the fuel, which is injected into the combustion chamber.
 Diesel engines are manufactured in two stroke and four stroke versions.
 Used to drive the prime mover of electric generators
 Used as a stand-by set for start up of auxiliaries in steam and gas power plants

12.  Used for emergency supply to hospitals, hotels, factories and in other commercial units.
Advantages:
 High operating efficiency.
 Need very little water for cooling.
 Quick start and stop is possible.
 Easier handling of fuel.