Category SOLAR RADIATION

Illuminance on Tilted Surfaces

[1] The daily total of radiation balance is computed for all 24-h intervals avail­able. If at least one hourly total value is missing, the daily total is not calcu­lated. For a missing data symbol, “-” is entered in the table instead.

[2] In computing daily totals, sunrise and sunset hour intervals are specially treated to avoid undue reduction in daily totals due to the gaps in the data for those hours:

If observational data are missing for the mentioned hour intervals on a number of days, the solar elevation angle e is computed for those hours.

[3] Site coordinates (latitude, longitude, elevation, time zone)

• Station pressure (calculated from site elevation and latitude if unknown)

producing the ai… di coefficients as a function of epsilon bin (1, 2, … , 8) are given in Table 8...

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Appendix F: Perez Anisotropic Model Coefficients for Luminous Efficacy and Zenith Luminance Model

TABLE F.1

Efficacy and Zenith Luminance Coefficients for Each Sky Condition Bin

Global Luminous Efficacy Direct Luminous Efficacy

E bin

a1

b1

c1

d1

a1

b1

c1

d1

1

96.63

-0.47

11.50

-9.16

37.20

-4.55

-2.98

117.12

2

107.45

0.79

1.79

-1.19

98.99

-3.46

-1.21

12.38

3

98.73

0.70

4.40

-6.95

109.83

-4.90

-1.71

-8.81

4

92.72

0.56

8.36

-8.31

110.34

-5.84

-1.99

-4.56

5

86.73

0.98

7.10

-10.94

106.36

-3.97

-1.75

-6.16

6

88.34

1.39

6.06

-7.60

107.19

-1.25

-1.51

-26.73

7

78.63

1.47

4.93

-11.37

105.75

0.77

-1.26

-34.44

8

99.65

1.86

-4.46

-3.15

101.18

1.58

-1.10

-8.29

Diffuse Luminous Efficacy

Zenith Luminance Value

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Appendix E: Photopic Response Function V(X) Curve

Lambda

Lambda

(nm)

Vlambda

(nm)

Vlambda

375.0

0.0000

394.5

0.0015

375.5

0.0000

395.0

0.0015

376.0

0.0000

395.5

0.0017

376.5

0.0000

396.0

0.0018

377.0

0.0000

396.5

0.0018

377.5

0.0000

397.0

0.0019

378.0

0.0000

397.5

0.0020

378.5

0.0000

398.0

0.0022

379.0

0.0000

398.5

0.0024

379.5

0.0001

399.0

0.0025

380.0

0.0002

399.5

0.0027

80.5

0.0002

400.0

0.0028

381.0

0.0002

401.0

0.0031

381.5

0.0002

402.0

0.0035

382.0

0.0003

403.0

0.0038

382.5

0.0003

404.0

0.0042

383.0

0.0003

405.0

0.0047

383.5

0.0003

406.0

0.0051

384.0

0.0003

407.0

0.0056

384.5

0.0004

408.0

0.0062

385.0

0.0004

409...

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Appendix D: SPCTRL2 FORTRAN Source Code

(+ is “continuation code” an for expression requiring multiple lines; “C” represents a comment line.)

Подпись: PROGRAM SPCTRAL2 ( INPUT,OUTPUT,TAPE5=INPUT,TAPE6=OUTPUT, +TAPE1,TAPE2,TAPE3)

Подпись: C C. C. C. C. C C. C C C C C C C C C C C C C C C C C C C C C C. C C C C C C C C C C C C C C C C C C C. ..TAPE1 = INPUT PARAMETERS

..TAPE2 = EXTRATERRESTRIAL SPECTRAL IRRADIANCE, ABSORPTION COEFFICIENTS. ..TAPE3 = OUTPUT FILE..TAPE5 = TERMINAL SCREEN

..THIS CODE WAS WRITTEN BY RICHARD BIRD AND CALCULATES SPECTRAL IRRADIANCE OR PHOTON FLUX ON A TILTED OR HORIZONTAL SURFACE. MODIFICATIONS TO THE CODE TO CONVERT SPECTRAL IRRADIANCE TO PHOTON FLUX PER WAVELENGTH OR ELECTRON VOLT WERE MADE BY CAROL RIORDAN. COMMENTS AND PROGRAM INSTRUCTIONS WERE ADDED BY RIORDAN 8/84.

******** INPUT VARIABLES ********

AI = ANGLE OF INCIDENCE OF DIRECT BEAM ON FLAT SURFACE (DEG)

ALPHA= POWER ON ANGSTRON TURBIDITY EXPRESSION (1.14 FOR RURAL)

NDAY = JULIAN DAY

NW = NUMBER OF WAVELENGTHS FOR THIS RUN O...

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Appendix C: Tables for CIE D65 Reference Spectrum and Spectral Daylight Temperature Model

TABLE C.1

CIE D65 Reference Spectrum Relative Amplitude,

S0, S-|, S2 Functions for Use in Equations 7.2-7.4

D65 Reference D50 Example

Wavelength

(nm)

Spectrum S(X) (Relative Units)

S0QO

MM

S2M

Calculation (Relative Units)

300

0.03

0.04

0.02

0.00

0.02

305

1.66

3.02

2.26

1.00

1.04

310

3.29

6.00

4.50

2.00

2.05

315

11.77

17.80

13.45

3.00

4.92

320

20.24

29.60

22.40

4.00

7.78

325

28.64

42.45

32.20

6.25

11.27

330

37.05

55.30

42.00

8.50

14.76

335

38.50

56.30

41.30

8.15

16.36

340

40.00

57.30

40.60

7.80

17.96

345

42.43

59.50

41.10

7.25

19.44

350

44.91

61.80

41.60

6.70

21.02

355

45.78

61.65

39.80

6.00

22.49

360

46...

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Appendix B: Excel Structure for DISC Model of Direct Normal Irradiance (DNI) from Global Horizontal Irradiance (GHI)

Tables B.1 and B.2 show the structure and functions for implementing the DISC (direct insolation simulation code) model in Excel®. Note the cell references rely on the exact structure of rows and columns shown. User values are entered in shaded cells.

TABLE B.1

User Location Input Parameters

Row

Column A Label/Vali

1

2

3

4

USER

5

INPUTS

6

Latitude

7

User Value (+N, – S)

8

Longitude

9

User Value (+E, – W)

10

Time Zone

11

User Value (-W, +E)

12

Stn. Pressure

13

User Value mB

14

Pstn/P0

15

= A13/1013.250

TABLE B.2

Functions to Be Entered in Row 2, from Columns G to W

Column

Label (Row 1)

Value or Function (Rows 2-8761)

B

Month

1 to 12

C

Day

1 to 28, 30, or 31

D

DO...

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Appendix A: Bird Clear Sky Model in Excel

Excel® Column A holds user inputs for Bird clear sky model in rows 6 to 29. Note the cell references rely on the exact structure of rows and columns shown. User values are entered in shaded cells. Bold text are labels for values to be entered in cell below label.

TABLE A.1

Bird Clear Sky Input Parameters

Row Number Column A, Label, Value, or Function 1 2

3

4

5

N/A

6

USER

7

INPUTS

8

Latitude

9

User Value (+N, – S)

10

Longitude

11

User Value (+E, – W)

12

Time Zone

13

User Value (-W, +E)

14

Station Pressure mB

15

User Value

16

Ozone atm-cm

17

User Value (0.0-0.35)

18

Water Vapor H2O atm-cm

19

User Value (0.0-6.0)

20

Aerosol Optical Depth (AOD) @ 500 nm

21

User Value (0.0-0.4)

22

AOD @ 3...

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CURRENT ISSUES AND FUTURE PROSPECTS

The primary issue for the user of any model is whether it is appropriate for the application or problem under investigation...

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