Paraboloid Dish
for Stirling Engine
Prof. Shireesh B. Kedare
Adjunct Associate Professor
Department of Energy Science and Engineering
IIT-Bombay
[e-mail]
[e-mail]
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Paraboloid Dishes with Stirling
Paraboloid Dishes with Stirling
Engine at Point Focus
Engine at Point Focus
100 m2 Dishes with Stirling Engine by SES for
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500 & 800 MW plants at Mojave Dessert, US
Paraboloid Dish with Point Focus
Paraboloid Dish with Point Focus
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56 m2 Dish with Stirling Engine at VIT, INDIA
Arun at Mahanand Dairy,
Latur, India
� = 0.75  {0.4 + 2.4x10-5 (Tm - Tamb) + 0.9x10-3 (sin �z) } (Tm - Tamb) /Ibn
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Large Solar Concentrator
Large Solar Concentrator
with Stirling Engine :
with Stirling Engine :
The indigenous design
The indigenous design
ARUN can be fitted with Stirling engine to
supply electrical power.
Stirling engine will have to be imported
presently or indigenous development required.
The power generated may require 50% to 70%
of the capital investment compared to Solar
Photo-Voltaic installations and may work with
capacity factor of 150 to 200%.
Solar farm for power generation is feasible.
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Issues related to R and D
Matching the dish with stirling engine for optimum
operating temperature
Efficiency of dish decreases with temperature
Efficiency of engine increases with temperature
Dish can be improved for achieving higher temperature
Improved optical efficiency
Reduced loss coefficient
Increased concentration ratio
Design of solar receiver integrated with stirling engine
Material limits for higher temperature
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Matching the dish with stirling engine: Optimum temperature
0.80
0.75
�= 0.8 - { 0.4 + 2.4 x 10-5 (Tm - Tamb)} X
0.70
where, X = (Tm-Tamb) / Ibn
0.65
0.60 750, 0.659
Concentrator efficeiency
0.55
0.50
Engine efficiency
0.45
0.40
750,0.35
0.35
0.30
750, 0.23
0.25
0.20
Overall efficiency
0.15
500 600 700 800 900 1000 1100 1200 1300 1400 1500
Operating temperature, K
Tamb = 300 K
Ibn = 650 W/m2 7
Efficiency,%
Matching the dish with stirling engine: Optimum temperature
80
�= 0.8 - { 0.4 + 2.4 x 10-5 (Tm - Tamb)} X
75
70.4
where, X = (Tm-Tamb) / Ibn
70
Concentrator efficiency
65
64.95
Ibn = 650 W/m2
Ibn = 950 W/m2
60
65.97
55
58.01
50
Stirling
53.61
Engine efficiency
45
44.15
40
34.82
31.0816
Ibn = 950 W/m2
35
30
31.1
25
Overall efficiency
29.13
Ibn = 650 W/m2
20
15
400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600
Operating temperature, K
Tamb = 300 K
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Efficiency,%
Large Solar Concentrator
Large Solar Concentrator
ARUN with Stirling Engine
ARUN with Stirling Engine
ARUN160 fitted with Stirling engine
ARUN160
Ap. Area 169 m2
Electrical Power 25 kWelect
Operating hours 2500 (6-9 h/d; 300-340 d/yr)
Annual Electricity 60,000-75,000 Units /
generated, kWh year
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Thanks
Prof. Shireesh B. Kedare
[e-mail]
[e-mail]
Department of Energy Science & Engineering
Indian Institute of Technology Bombay
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