Casio fx-CG 50: Solar Panel Calculations
Note: The calculator programs can be modified for the monochrome Casio graphing calculators by removing the Color commands (Black, Blue, etc.). The programs use ClrText and Locate to generate a result screen.
Optimum Tilt of a Solar Panel
The program SLRPANEL estimates the optimum tilt of a solar panel given your latitude (North/South), time of day, and day of the year. The program assumes a 365 day year.
For the time of day, enter the time in hours before noon. Example: For 9:00 AM, enter 3. For 3:00 PM, enter -3.
The declination of the sun is estimated at:
δ ≈ -23.44° * (cos(360°/365° * (n + 10)))
n = number of days from January 1, n = 0 for January 1.
The program is listed in text file mode.
Casio fx-CG50 Program: SLRPANEL
(464 bytes)
'ProgramMode:RUN
Deg
ClrText
Locate 1,1,"SOLAR PANEL TILT"
Yellow Locate 1,3,"EWS 2022"
For 1->I To 750:Next
ClrText
"365 DAY YEAR ASSUMED"
"MONTH"?->M
"DAY"?->D
"HOURS FROM NOON"?->T
"LATITUDE (N//S)"?->L
0->X
M>2=>Int (0.4*M+2.3)->X
31*(M-1)+D-X-1->N
(-)23.44*(cos (360/365*(N+10)))->E
sin^-1 (sin L*sin E+cos E*cos L*cos (15*T))->H
sin^-1 (sin (15*T)*cos E/cos H)->Z
Z=0=>1Exp(-)9->Z
2/3*(tan^-1 (tan H/tan Z)-30)->P
ClrText
Black Locate 1,1,"MONTH:"
Blue Locate 8,1,M
Black Locate 11,1,"DAY:"
Blue Locate 16,1,D
Black Locate 1,3,"DEC:"
Blue Locate 7,3,E
Blue Locate 21,3,"_deg_"
Black Locate 1,5,"TILT:"
Blue Locate 7,5,P
Blue Locate 21,5,"_deg_"
Example:
April 30, 11:30 AM, at Latitude 40°20'11"
Inputs:
Month: 4
Day: 30
Hours From Noon: 0.5
Latitude: 40°20°11° ( [ OPTN ], [ F6 ] ( > ), [ F5 ] (ANGLE), [ F4 ] ( ° ' " ))
Result Screen:
MONTH: 4 DAY: 30
DEC: 14.18251427 °
TILT: 34.39287954 °
Solar Energy Reflected
Given an incidence angle and the type of material, the program SOLARENG estimates the ratio of solar reflected. The program offers three types of material:
Glass, average index of refraction of 1.52 is used
Silicon, average index of refraction of 3.45 is used
Diamond, average index of refraction of 2.417 is used
The program is listed in text file mode.
Casio fx-CG50 Program: SOLARENG
(324 bytes)
'ProgramMode:RUN
Deg
"INCIDENCE ANGLE"?->I
Menu "MATERIAL","GLASS",1,"SILICON",2,"DIAMOND",3
Lbl 1:1.52->R:Goto 4
Lbl 2:3.45->R:Goto 4
Lbl 3:2.417->R:Goto 4
Lbl 4
sin^-1 (sin I/R)->W
0.5*((sin (I-W))^<2>/(sin (I+W))^<2>+(tan (I-W))^<2>/(tan (I+W))^<2>)*100->P
ClrText
Black Locate 1,1,"AT ANGLE "
Black Locate 10,1,I
Black Locate 21,1,"_deg_"
Green Locate 1,2,"INDEX="
Red Locate 9,2,R
Green Locate 1,3,"REFLECT="
Red Locate 9,3,P
Red Locate 21,3,"%"
Example:
Incidence Angle: 6°, glass
Inputs:
INCIDENCE ANGLE: 6
MATERIAL: 1: GLASS
Result Screen:
AT ANGLE 6 °
INDEX = 1.52
REFLECT = 4.25820312 %
HP 32S and HP 32SII Week: May 2, 2022 - May 6, 2022
Source:
Rosenstein, Morton. Computing With the Scientific Calculator Casio 1986 ISBN-13: 978-1124161433
Eddie
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