1

Paraboloid Dish

for Stirling Engine

Prof. Shireesh B. Kedare

Adjunct Associate Professor
Department of Energy Science and Engineering
IIT-Bombay

[e-mail]
[e-mail]

2

Paraboloid Dishes with Stirling

Paraboloid Dishes with Stirling

Engine at Point Focus

Engine at Point Focus

100 m

2

Dishes with Stirling Engine by SES for

500 & 800 MW plants at Mojave Dessert, US

3

Paraboloid Dish with Point Focus

Paraboloid Dish with Point Focus

56 m

2

Dish with Stirling Engine at VIT,

INDIA

4

Arun at Mahanand Dairy,
Latur, India

η

= 0.75 – {0.4 + 2.4x10-5 (Tm - Tamb) + 0.9x10-3 (sin θz) } (Tm - Tamb) /Ibn

5

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.

6

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

7

Matching the dish with stirling engine: Optimum temperature

500

600

700

800

900

1000 1100 1200 1300 1400 1500

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.55

0.60

0.65

0.70

0.75

0.80

750, 0.659

750, 0.23

750,0.35

η

= 0.8 - { 0.4 + 2.4 x 10

-5

(T

m

- T

amb

)} X

where, X = (T

m

-T

amb

) / I

bn

E

ff

icienc

y,

%

Operating temperature, K

Concentrator efficeiency

Engine efficiency

Overall efficiency

T

amb

= 300 K

I

bn

= 650 W/m

2

8

400

500

600

700

800

900 1000 1100 1200 1300 1400 1500 1600

15

20

25

30

35

40

45

50

55

60

65

70

75

80

η

= 0.8 - { 0.4 + 2.4 x 10

-5

(T

m

- T

amb

)} X

where, X = (T

m

-T

amb

) / I

bn

58.01

64.95

31.1

34.82

29.13

31.0816

53.61

44.15

65.97

70.4

Ef

ficiency,

%

Operating temperature, K

Stirling
Engine efficiency

Overall efficiency

I

bn

= 650 W/m

2

I

bn

= 950 W/m

2

I

bn

= 650 W/m

2

Concentrator efficiency

I

bn

= 950 W/m

2

T

amb

= 300 K

Matching the dish with stirling engine: Optimum temperature

9

ARUN160 fitted with Stirling engine

25 kW

elect

Electrical Power

2500

(6-9 h/d; 300-340 d/yr)

Operating hours

60,000-75,000 Units /

year

Annual Electricity

generated, kWh

169 m

2

Ap. Area

ARUN160

Large Solar Concentrator

Large Solar Concentrator

ARUN

ARUN

with Stirling Engine

with Stirling Engine

10

Thanks

Department of Energy Science & Engineering

Indian Institute of Technology Bombay

Prof. Shireesh B. Kedare

[e-mail]

[e-mail]