How to use this tool
Check the units, enter your values, and run the tool. Results follow the assumptions and method below.
Calculation method
Geometric solar elevation
asin(min(1,max(-1,(sin(latitude*pi/180)*sin((0.006918-0.399912*cos((2*pi/365*(day-1+(hour-12)/24)))+0.070257*sin((2*pi/365*(day-1+(hour-12)/24)))-0.006758*cos(2*(2*pi/365*(day-1+(hour-12)/24)))+0.000907*sin(2*(2*pi/365*(day-1+(hour-12)/24)))-0.002697*cos(3*(2*pi/365*(day-1+(hour-12)/24)))+0.00148*sin(3*(2*pi/365*(day-1+(hour-12)/24)))))+cos(latitude*pi/180)*cos((0.006918-0.399912*cos((2*pi/365*(day-1+(hour-12)/24)))+0.070257*sin((2*pi/365*(day-1+(hour-12)/24)))-0.006758*cos(2*(2*pi/365*(day-1+(hour-12)/24)))+0.000907*sin(2*(2*pi/365*(day-1+(hour-12)/24)))-0.002697*cos(3*(2*pi/365*(day-1+(hour-12)/24)))+0.00148*sin(3*(2*pi/365*(day-1+(hour-12)/24)))))*cos(((hour*60+(229.18*(0.000075+0.001868*cos((2*pi/365*(day-1+(hour-12)/24)))-0.032077*sin((2*pi/365*(day-1+(hour-12)/24)))-0.014615*cos(2*(2*pi/365*(day-1+(hour-12)/24)))-0.040849*sin(2*(2*pi/365*(day-1+(hour-12)/24)))))+4*longitude-60*zone)/4-180)*pi/180)))))*180/piSolar zenith angle
acos(min(1,max(-1,(sin(latitude*pi/180)*sin((0.006918-0.399912*cos((2*pi/365*(day-1+(hour-12)/24)))+0.070257*sin((2*pi/365*(day-1+(hour-12)/24)))-0.006758*cos(2*(2*pi/365*(day-1+(hour-12)/24)))+0.000907*sin(2*(2*pi/365*(day-1+(hour-12)/24)))-0.002697*cos(3*(2*pi/365*(day-1+(hour-12)/24)))+0.00148*sin(3*(2*pi/365*(day-1+(hour-12)/24)))))+cos(latitude*pi/180)*cos((0.006918-0.399912*cos((2*pi/365*(day-1+(hour-12)/24)))+0.070257*sin((2*pi/365*(day-1+(hour-12)/24)))-0.006758*cos(2*(2*pi/365*(day-1+(hour-12)/24)))+0.000907*sin(2*(2*pi/365*(day-1+(hour-12)/24)))-0.002697*cos(3*(2*pi/365*(day-1+(hour-12)/24)))+0.00148*sin(3*(2*pi/365*(day-1+(hour-12)/24)))))*cos(((hour*60+(229.18*(0.000075+0.001868*cos((2*pi/365*(day-1+(hour-12)/24)))-0.032077*sin((2*pi/365*(day-1+(hour-12)/24)))-0.014615*cos(2*(2*pi/365*(day-1+(hour-12)/24)))-0.040849*sin(2*(2*pi/365*(day-1+(hour-12)/24)))))+4*longitude-60*zone)/4-180)*pi/180)))))*180/piSolar declination
(0.006918-0.399912*cos((2*pi/365*(day-1+(hour-12)/24)))+0.070257*sin((2*pi/365*(day-1+(hour-12)/24)))-0.006758*cos(2*(2*pi/365*(day-1+(hour-12)/24)))+0.000907*sin(2*(2*pi/365*(day-1+(hour-12)/24)))-0.002697*cos(3*(2*pi/365*(day-1+(hour-12)/24)))+0.00148*sin(3*(2*pi/365*(day-1+(hour-12)/24))))*180/piEquation of time
(229.18*(0.000075+0.001868*cos((2*pi/365*(day-1+(hour-12)/24)))-0.032077*sin((2*pi/365*(day-1+(hour-12)/24)))-0.014615*cos(2*(2*pi/365*(day-1+(hour-12)/24)))-0.040849*sin(2*(2*pi/365*(day-1+(hour-12)/24)))))