It tells about how the power is generated from solar power stirling engine and what are their advantages and disadvantages

1. SOLAR POWER STIRLING
ENGINE FOR SELF GENERATING
ELECTRICITY
DONE BY:
GROUP 7
Hadi Razak 268
Praveen Raghav 269
Charishma 270
Kundan Reddy 274

2. ABSTRACT
2
In this energy deficient world, it is strongly felt that the use of solar energy as a possible
source is not being fully utilized. So in attempt to deploy its use, a novel concept of
“solar powered Stirling engine” is introduced.
In this we use a Stirling engine to generate electricity. A Stirling Engine is basically a
heat engine that operate by cyclic compression and expansion of air or other gases.
The solar power Stirling engine is coupled with a generator to produce power.
This method of power production has no pollution, no noise. This is proven to be the
most efficient way to convert solar Energy to electric power. It is twice efficient and five
times cost-efficient than the conventional method using photo voltaic cells.
This engine is currently exciting as it is more efficient and safer than a comparable
steam engine. Stirling engines are also being looked by NASA for the use in space
exploration

3. 3
What basically Stirling Engine is?
Reciprocating engine.
External combustion (get heat from external source).
Converts heat energy into mechanical power by alternately compressing and
expanding a fixed quantity of the working fluid at different temperatures.
Work on both conventional and non conventional sources
Efficient , clean & silent

4. 4
BASIC STIRLING ENGINE
1. Pink – Hot cylinder wall
2. Dark grey – Cold cylinder wall
3. Yellow – Coolant inlet and outlet pipes
4. Dark green – Thermal insulation separating the two cylinder ends
5. Light green – Displacer piston
6. Dark blue – Power piston
7. Light blue –Linkage crank and flywheel

5. 5
MANUFACTURING OF SOLAR
STIRLING POWER SYTEM
 A parabolic dish is used to get heat from
the sun, and for reflection of sun light the
aluminum foil is used there.
 The size of the parabolic collector is
depending upon the power of Stirling
engine.
 Then a Stirling engine is placed at the
focal point of the solar collector.
 The electric generator is also coupled
with the Stirling engine.
 When cylinder of engine get hot by the
sun heat then it starts working thus power
produces by the generator.

6. 6
THE VIEW OF 500MW POWER PLANT
OPERATED BY SOLAR STIRLING ENGINE
IN USA CALIFORNIA

7. 7
SYSTEM DESIGN CALCULATION
I) Solar Calculations
In order to find the total radiation received in a day, radiation received in
Chennai on a day are taken as reference. This is shown in given table
Time(hrs) Radiation(W/m2) Time(hrs) Radiation(W/m2)
1:00 0 13:00 919
2:00 0 14:00 792
3:00 0 15:00 609
4:00 0 16:00 390
5:00 0 17:00 149
6:00 61 18:00 0
7:00 282 19:00 0
8:00 521 20:00 0
9:00 722 21:00 0
10:00 874 22:00 0
11:00 963 23:00 0
12:00 978 24:00 0

8. 8
0
200
400
600
800
1000
1200
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Solar Radiation in Chennai
Solar Radiation in Chennai
Now, to find the total solar radiation received by the parabolic dish, we need to
calculate its area. So, assuming the dish to be elliptical in shape, it’s area is
calculated as:
By measurement,
Length of major axis of the dish (a)= 0.71m
Length of minor axis of the dish(b)= 0.58m
So,
Area of dish= πab=π∗0.71∗0.58=1.29m²

9. 9
With this area, total radiation received in a day is illustrated in given table
Radiation (W/m2) Area(m2) Total Reflected
Radiation per day(W)
0 1.29 0
61 1.29 78.69
282 1.29 363.78
521 1.29 672.09
722 1.29 931.38
874 1.29 1127.46
963 1.29 1242.27
978 1.29 1261.62
919 1.29 1185.51
792 1.29 1021.68
609 1.29 785.61
390 1.29 503.1
149 1.29 192.21
Total= 9432.72

10. 10
POWER GENERATION
• Solar Heat energy source can be used
• Convert solar power into mechanical power
• Operate by letting heat flow of a hot source
• Efficiency is more than photo voltaic cell

11. 11
MOTORING ACTION
The idealized Stirling engine has four thermodynamic processes acting on the
working fluid:
I. PROCESS 1 :
Most of the working gas is in contact with the
hot cylinder walls, it has been heated and expansion
has pushed the cold piston to the bottom of its travel
in the cylinder .The expansion continues in the cold
cylinder, which is 90° behind the hot piston in its cycle,
extracting more work from the hot gas.

12. 12
II. PROCESS 2 :
The gas is now at its maximum volume. The hot cylinder
piston begins to move most of the gas into the cold
cylinder, where it cools and the pressure drops.
III. PROCESS 3 :
Almost all the gas is now in the cold cylinder and cooling
continues. The cold piston, powered by flywheel momentum
(or other piston pairs on the same shaft) compresses the
remaining part of the gas.

13. 13
IV. PROCESS 4 :
The gas reaches its minimum volume, and it will now
expand in the hot cylinder where it will be heated once
more, driving the hot piston in its power stroke.
Thus this cycle repeats to produce rotary motion at the output thereby
producing mechanical energy.

14. 14
STIRLING GENERATORS STORING ENERGY BY
MOLTEN SALTS SYSTEM

15. 15
MOLTEN SALT SYSTEM
Mixture of nitrate salts heated in tubes up to 565°c Returns to hot storage
tank.
Hot salt fluid pumped for generating purposes.
The salt at 265°c returns to cold storage tanks used in Rankin cycle again.
Tubes in receiver designed to Absorbs 95% of the incidence of sun light.
Total molten salt loop designed <2500 feet which is heat traced to prevent
freezing.

16. 16
THE STIRLING CYCLE
 The Stirling cycle comes closest to the Carnot cycle
efficiency while having a
higher work ratio.
 Despite the fact that the efficiency may not be
practical in real fabrication and
testing, the Stirling engine gives the best output.
 The idealized stirlining cycle consists of four
thermodynamic process acting on network of the
fluid
1-2: Constant volume heat addition
2-3: Isothermal expansion
3-4: Constant volume heat removal
4-1: Isothermal compression:

17. 17
EFFICIENCY
The efficiency is defined to be:
Where
 W is the work done by the system (energy exiting the system as work)
 QH is the heat put into the system (heat energy entering the system)
 Tc is the absolute temperature of the cold reservoir
 TH is the absolute temperature of the hot reservoir

18. 18
Solar energy is focused on the Solar Receiver that is converted to 25KW of
electricity for a peak conversion efficiency of approximately 31.25%. SES (stirling
energy systems) holds the world record of 31.25% efficiency for solar isolation to grid
commercial power

19. 19
SCOPE IN INDIAN MARKET
• On a medium-Large scale electricity generation
• For industries
• On a small scale- home and buildings
• Rural electrification

20. 20
LARGE SCALE ELECTRICITY GENERATION
The cost of electricity generated is cheapest when compared to other solar
techniques.
AC output
No need of another setups
There is no need for new transmission lines
FOR INDUSTRIES
Reduced power cuts
Each unit can generate from 10KW or even lower up to 1MW
Each individual unit is capable of producing electricity
An industrial area can be given its own power generation instead of each
company as no larger scale, the system are cost effective

21. 21
ON A SMALL SCALE
RURAL ELECTRIFICATION
Better than photo voltaic systems.
Gated communities, municipalities etc
24 hour electricity guarantee is an attractive feature to put up
To reduce transmission losses
Solar Stirling Generators can be set up in the village premises itself.
Single plant can be used for various surrounding villages

22. 22
THE CURRENT AND PAST
APPLICATIONS OF STIRLING ENGINES
Military uses
Spatial domain
Solar applications
Research and oceanographical exploitation
Domestic uses
Heating & cooling purposes

23. 23
ADVANTAGES
The high efficiency
Multitude of sources
Non-Polluting
Reliability and easy maintenance
Low risks
Duality
Easy balance

24. 24
DISADVANTAGES
The variety of models
The problems of sealing
Heat transfers
The lack of flexibility

25. 25
CONCLUSION
Today, Stirling engines are used in some very specialized applications, like in
submarines or auxiliary power generators, where quiet operation is important.
Stirling engines are unique heat engines because their theoretical efficiency is
nearly equal to their theoretical maximum efficiency, known as the Carnot Cycle
efficiency.
The best (and presumably most expensive) of current practical photovoltaic
systems convert about 22% of the available solar energy into electricity. This
mechanical system claims 24%, and all using ordinary low-environmental-
impact materials and manufacturing techniques. Unlike fancy semiconductor
solar panels.