Solar position calculator is a calculator program that returns solar zenith angle, declination, Julian day, equation of time, hour angle, instantaneous and daily extraterrestrial radiation values, and sunrise and sunset times.
Equations were provided by the National Renewable Energy Laboratory.
Go to the Solar position calculator...
There is also the Sun path chart program that creates sun path charts in Cartesian coordinates for: (1) "typical" dates of each month (i.e.; days receiving about the mean amount of solar radiation for a day in the given month); (2) dates spaced about 30 days apart, from one solstice to the next; or (3) a single date you specify. You can select whether hours are plotted using local standard time or solar time. In addition, there are a number of options available to allow you to alter the chart's appearance.
Resulting charts are displayed in your Web browser window, and they are meant to be printed out. Two formats are currently available: PDF (Adobe) and PNG (a standard international graphics format).
The create sun path charts in polar coordinates go to the polar sun path charts Web page. For more information, visit our Web page about using sun charts.
Go to the Sun path chart program...