The document discusses thermal energy generation focused on converting heat to electricity, highlighting fossil fuels like coal as the primary source due to their abundance and efficiency. It describes various power generation technologies, including gas and steam turbines, and covers thermodynamic cycles and their applications in power plants. The document also touches on the environmental challenges of coal use and potential technologies for carbon capture and storage to mitigate CO2 emissions.

1. THERMAL
ENERGY
GENERATION

2. INTRODUCTION
• Thermal Energy generation is the process of
generating electricity from heat. Heat is a
form of energy. Heat energy that is turned
into electricity can be made in many ways.
It can be produced by burning
fuels such as
coal, oil, gas or wood.
It can also be taken from steam

3. Coal-fired power
generation todayCoal’s place
in the energy mix
Coal is by far the most abundant fossil
fuel, with
proven global reserves of nearly 1
trillion tonnes
,enough for 150 years of generation at
current consumption rates (BGR,
2010). In terms of
energy content, reserves of coal are
much greater
than those of natural gas and oil.
Recoverable
reserves of coal can be found in more
Coal has satisfied the major part of the
growth in
electricity over the past decade. Even
though non fossil power generation has
risen considerably over the past two
decades, it has failed to keep pace with
the growth in generation from fossil
fuels. Between 1990 and 2010,
generation from nuclear power rose by
492 TWh, from hydro renewables by 1
334 TWh and from non-hydro renewable
energy technologies by 454 TWh. By
contrast, generation from coal grew by 4

7. Kelanitissa Power Station (Gas Turbines and a combined
cycle power station)
• Kelanitissa Power Station consists of 7 Gas Turbines
(GT) (six 17MW GTs; one 115 MW GT) and a combined
cycle power plant of capacity 165 MW.
Sapugaskanda Power Station (heavy fuel)
• Sapugaskanda Power Station consists of four 20 MW
generators and eight 10MW generators run on heavy
fuel oil.
Lakvijaya Power Plant (coal)
• Lakvijaya power station has a 300 MW generator run
POWER PLANTS OWNED
BY CEB

8. Independent Power
Producers (IPPs)• Asia Power (Private) Limited
There are 8 machines, each 6.35 MW. These Machines
usually do not run on partial loads when dispatched.
Therefore following plan was used for the test.• Colombo Power (Private) Limited
There are 4 machines, each 15 MW.
• Ace Power Embilipitiya (Private) Limited
There are 14 machines, each 7 MW.
• AES Kelanitissa (Private) Limited
The capacity of the plant is 163 MW
• West Coast Power (Private) Limited
The capacity of the plant is 270 MW, a combined cycle gas
turbine power plant.

9. Thermodynamic cycles
Thermodynamic cycles can be divided into two
general categories:POWER CYCLES REFRIGERATION
CYCLESThermodyna
mic cycles
that
engines/powe
r plants are
operate on
Thermodynamic
cycles that
refrigerators,
air conditioners,
or heat pumps
are operate on

10. Other
categorizations
Gas Cycle Vapour cycles
Depending on the phase of the working
fluid
The working fluid
remains in the
gaseous phase
throughout the
entire cycle
the working fluid exists
in the vapor phase
during one part of the
cycle and in the liquid
phase during another
part.
Another way: closed and open cycles.
In closed cycles- The working fluid is returned
to the initial state at the end of the cycle and
is re-circulated.In open cycles- The working fluid is renewed at the

11. Power
CyclesThe cycles in actual devices are difficult to analyze ;
Presence complicating effects,such as friction, and the absence
of sufficient time for establishment of the equilibrium
conditions during the cycle.
cycle that idealized and simplified for resembling of the actual
cycle closely Ideal Cycle
The idealizations and simplifications commonly employed in the
analysis of power cycles:1. The cycle does not involve any friction.
Therefore, the working fluid does not experience any pressure
drop as it flows in pipes or devices.2. All expansion and compression processes take place in a quasi
equilibrium manner.3. The pipes connecting the various components of a system are
well insulated, and heat transfer through them is negligible.
4. Neglecting the changes in kinetic and potential energies of the

12. Gas Power
CyclesApproximations utilize for simplifying the actual gas power
cyclesAIR-STANDARD
ASSUMPTIONS:1) The working fluid is air, which continuously circulates in a closed loop and
always behaves as an ideal gas.
2) All the processes that make up the cycle are internally reversible.
3) The combustion process is replaced by a heat-addition process from an
external source
4) The exhaust process is replaced by a heat-rejection process that restores theCold Air-standard Assumption: The specific heats are constant at their

13. ENERGY
CONVERSION
PLANT AND
THERMODYANA
MIC CYCLE
1.STEAM
TURBINES
(Rankine
Cycle)
2.GAS
TURBINES
(BRYTON
CYCLE)
4.DIESEL
AND OTTO
CYCLES
5.BINARY
CYCLES
3.MAGNET
O HYDRO
DYNAMIC
GENERATO
R

14. 1. STEAM TURBINES (RANKINE
CYCLE)
APPLICATIONS
•FOSSIL FUEL POWER
PLANT
•COMBINED CYCLE
POWER PLANT
•GEOTHERMAL POWER
PLANT
•SOLAR POWER PLANT
•OCEAN THERMAL
25-30
%
THERMAL
EFFICIENCY

15. 2. GAS TURBINES (BRYTON
CYCLE)
APPLICATIONS
•GAS TURBINE POWER
PLANT
•COMBINED CYCLE
POWER PLANT
27-38
THERMAL
EFFICIENCY

16. 3. MAGNETO HYDRO DYNAMIC
GENERATOR
APPLICATIONS
• TOPPING CYCLE WITH STEAM
POWER PLANT
45-60
THERMAL
EFFICIENCY

17. 4. DIESEL AND OTTO CYCLES
APPLICATIONS
• PEAKING POWER
PLANT
• STAND ALONE
POWER PLANT
• STANDBY POWER
PLANT
• VEHICALS
• SHIPS
35 %
THERMAL
EFFICIENCY

18. 5.BINARY CYCLES
APPLICATIONS
• GEOTHERMAL POWER PLANT
• SOLAR POWER PLANT
• OCEAN THERMAL POWER PLANT
UP TO
THERMAL
EFFICIENCY

19. VAPOUR POWER
CYCLES

20. What is Vapour Power
cycles?
• Thermodynamic cycle
• Used in power plants
• Working fluid is alternatively
vaporized and condensed
• Most common working fluid -
Steam

21. Types of Vapour Power Plants –
Depending on fuel use

22. The components of four alternative
vapour power plant configurations
I . Fossil-fuel vapour
power plant.

23. The components of four alternative vapour
power plant configurations
Pressurized-water reactor
nuclear vapour power plant

24. The components of four alternative
vapour power plant configurations
Concentrating solar thermal
vapour power plant.

25. The components of four alternative
vapour power plant configurations
Geothermal vapour
power plant.

26. Rankine Cycle

27. RANKINE CYCLE
• Most large electricity generating plants (central power
stations), and very large ship engines, use water vapour
(steam) as working fluid, following some variation of the
basic Rankine cycle (named after the Scottish inventor
William Rankine, that in 1859 wrote the first book on
Thermodynamics), the only vapour power cycle in practical
use since 1840 until in 1984 Alexander Kalina patented in
the USA the cycle named after him. The heat source for the
boiler is usually the combustion products of a fuel (mainly
coal) and air, or the primary refrigerant of a nuclear
reactor, and the heat sink in the condenser is usually a
water loop, open like in a river, or closed like in a cooling.
Thomas Newcomen is credited with the invention of the

28. •The processes taking place in a vapour
power plant are complicated.
•Idealizations are required to develop
thermodynamic models of plant.
•Four principal components:
i. turbine,
ii. condenser,
iii.pump, and
iv. boiler
steady-
flow
devices
Ideal Rankine
Cycle

29. The Rankine cycle is a heat engine with a vapour power cycle. The
common working fluid is water. The cycle consists of four processes as
shown in Figures 1 (a) and 1 (b):
1 to 2: Isentropic expansion (Steam turbine)1 An isentropic process, in which the entropy
of working fluid remains constant.
2 to 3: Isobaric heat rejection (Condenser) An isobaric process, in which the pressure of
working fluid remains constant.
3 to 4: Isentropic compression (Pump) During the isentropic compression process, external
work is done on the working fluid by means of pumping operation.
4 to 1: Isobaric heat supply (Steam Generator or Boiler) During this process, the heat from
the high temperature source is added to the working fluid to convert it into
superheated steam.

30. Simple Ideal Rankine
Cycle

31. Process 1-2: Water from the
condenser at low pressure is
pumped into the boiler at high
pressure. This process is
reversible adiabatic.
Process 2-3: Water is
converted into steam at
constant pressure by the
addition of heat in the
boiler.
Process 3-4: Reversible
adiabatic expansion of steam
Process 4-1: Constant pressure heat
rejection in the condenser to

32. Ideal Rankine
Cycle
State 1:
• Water enters the pump as saturated liquid .
• Compressed isentropically to the operating pressure of
the boiler.
• Steady-flow energy equation :
or

33. State 2:
• Water enters the boiler as a compressed
liquid and leaves as a superheated vapour.
• boiler - a large heat exchanger (often
called the steam generator)
Steady-flow energy
equation :
Ideal Rankine
Cycle

34. State 3:
• The superheated vapour enters the turbine
.
• expands isentropically
• produces work by rotating the shaft
connected to an electric generator
• pressure and the temperature of steam
drop
• Steady-flow energy equation :
Ideal Rankine
Cycle

35. State 4:
• Steam enters the condenser .
• usually a saturated liquid–vapour mixture
with a high quality
• condensed at constant pressure
• leaves the condenser as saturated liquid
• Steady-flow energy equation :
Ideal Rankine
Cycle

36. http://energy.sdsu.edu/testhome/vtAnimations/animations/chap
9/A-steamPower/basicRankineCycle.html

37. Simple Ideal Rankine
Cycle
Thermal Efficiency:

38. Example:
Consider a steam power plant operating on the
simple ideal Rankine cycle. Steam enters the turbine
at 3 MPa and 350°C and is condensed in the
condenser at a pressure of 75 kPa. Determine the
thermal efficiency of this cycle.

39. Exam
ple:

41. Improving Performance of Rankine
cycle
Modifications to Improve Performance
• Superheat
• Reheat
• Regeneration (Feed water
heating)

42. •Superheat:
•further energy can be
added
• total area under the
process curve 3-
3’represents the
increase in the heat
input
•decreases the
moisture content of
Modifications to Improve
Performance

43. •Superheat:
•not limited to having
saturated vapour at the
turbine inlet
•increase in the
temperature value
depends on improving
the present materials
Modifications to Improve
Performance

44. •Reheat:
Modifications to Improve
Performance

45. •Reheat:
•steam expands through
a first-stage turbine
(Process 1–2) to some
pressure between the
steam generator and
condenser pressures.
•steam is then reheated
in the steam generator
(Process 2–3)

46. •Reheat:
• After reheating, the
steam expands in a
second stage turbine to
the condenser pressure
(Process 3–4)
• avoid low-quality steam
at the turbine exhaust
• higher boiler pressures
• temperature of the steam
entering the turbine is
restricted by
metallurgical limitations

47. •Regeneration (Feed Water
Heating):
Modifications to Improve
Performance

48. •Regeneration (Feed
Water Heating):
•heat is transferred to
the working fluid
during process 2-2 at
a relatively low
temperature.
•This lowers the
average heat addition
temperature and thus
Modifications to Improve
Performance

49. •Regeneration (Feed
Water Heating):
• raise the temperature of
the liquid leaving the
pump (called the feed-
water) before it enters
the boiler.
• A practical regeneration
• extracting, or
“bleeding,” steam from
the turbine at various
Modifications to Improve
Performance

50. •Regeneration (Feed Water Heating):
not only improves cycle efficiency, but
also provides
•a convenient means of deaerating the
feedwater (removing the air that leaks in
at the condenser) to prevent corrosion in
the boiler
•A practical regeneration control the large
Modifications to Improve
Performance

51. GAS POWER CYCLES

52. Gas power plant
• Gas turbines - lighter and more compact than the vapor
power plants.
• Electric power producing gas turbines - almost
exclusively fueled by natural gas.
• Other main application of Brayton cycle is air craft Jet
propulsion
• Depending on the application, other fuels can be used
•distillate fuel oil;
•propane;
•gases produced from landfills, sewage treatment

53. Ideal Brayton
Cycle

54. Ideal (Air Standard)
Brayton Cycle
•Open cycle • Closed (air standard )
cycle

55. Ideal Brayton Cycle

56. Ideal Brayton Cycle
• All four processes executed in
steady flow devices.
energy balance for a steady-
flow process

57. Combine Gas and
Steam Cycle

58. Combine Gas and Steam
Cycle• The gas-turbine (Brayton) cycle topping a
steam turbine (Rankine) cycle, which has a
higher thermal efficiency than either of the
cycles executed individually.
• Use the high temperature exhaust gases as the
energy source for the bottoming cycle such as
a steam power cycle.
• The combined cycle increases the efficiency

59. Combine Gas and Steam
Cycle

60. OTTO CYCLE
• The Otto cycle is a first approximation
to model the operation of a spark-
ignition engine, first built by Nikolaus
Otto in 1876, and used in many cars,
small planes and small power systems
(below say 200 kW) down to miniature
engines. This is a reciprocating internal
combustion gas engine, in contrast to
the, at that time master, external
combustion steam engine. The Otto
engine is sketched in Figure, where the
typical terms are introduced for engine-
geometry characteristics (stroke, bore,
displacement and compression ratio);

61. air, which is assumed to follow four processes (Fig.) :
isentropic compression,
constant-volume heat
input from the hot source,
isentropic expansion,
constant-volume heat
rejection to the environment.

62. DIESEL CYCLE
• The Diesel cycle is a first approximation to model the operation of a
compression-ignition engine, first built by Rudolf Diesel in 1893, and
used in nearly all boats (the first in 1903), nearly all trucks (the first
in 1923), many locomotives (the first one in the 1940s, but taken
over by electric drive after a few decades of prominence), most cars
nowadays (the first one in 1936, but it took decades to gain market),
many medium-large electric auxiliary-power and cogeneration
systems, and even some small airplanes. It is the reference engine
from 50 kW to 50 MW, due to the fuel used (cheaper and safer than
gasoline) and the higher efficiency. This is a reciprocating internal
combustion engine, (the fuel is injected at very high pressures, up to
200 M Pa, to ensure immediate vaporization). One of its key
advantages compared to Otto engines is the great load increase per
cylinder associated to the higher pressures allowed (the mixture of
fuel and air would detonate in Otto engines at high compressions),

63. In the ideal air-standard Diesel cycle, the working
fluid is just air, which is assumed to follow four
processes (Fig.): isentropic compression, constant-
pressure heat input from the hot source, isentropic
expansion, and constant-volume heat rejection to the
environment.

65. BASIC PRINCIPLES OF
SITTING AND DESIGN OF
STEAM POWER STATIONS

66. • When planning a steam electric power station it is
necessary to take into account the following
1. The raw material, coal, has to be taken to the boiler via
bunkers similar conditions apply in respect
of peat but vary somewhat for oil firing.
2. The produce of combustion in boilers, ash-flue dust and
gases have to be disposed of.
3. The steam generated in the boiler plant has to be
delivered to the turbine by the shortest possible route.
4. The cooling tower has to be delivered to and discharged
from the turbine condensing plant and may have to be re
cooled, where re cooling is necessary then spray ponds/or
cooling towers will be required.

67. •The major challenges to the continued use of
coal arise from its environmental impact.
Although reducing emissions of sulphur dioxide
(SO2), nitrogen oxides (NOX) and particulate
matter (PM) from coal-fired power generation is
important, particularly at the local or regional
level, the spotlight globally in recent years has
ENVIRONMENTAL ASPECTS
ENERGY AND POLLUTION CONTROL

68. CO2 Capture and Storage - The Long Term Vision for Clean
Power Generation from Coal
Both fossil and non-fossil forms of energy will be needed in the
foreseeable future to meet global energy requirements. Fossil fuels, in
particular coal for power generation, are available on a long-term basis
and their continued large-scale and widespread use is necessary in orde
to sustain economic growth. It is therefore important that technological
solutions be commercialized which allow the use of fossil fuels with
greatly reduced CO2 emissions. CO2 capture and storage (CCS) offers
sound potential for the future; however,
further work is required on:
Suitable power plant technology with CO2 capture; and
Environmentally acceptable and reliable CO2 sequestration and use.
Possible technologies for CO2 capture from coal-fired power plants can
be categorised as: