I'm using the Type99 user defined data reader and radiation processor and am receiving very unrealistic values of the incidence angle. I'm reading data for location in California at 119.98 W, 35.69 N, and have provided the header to the data file as shown below:
Here's how July 1st looks like in terms of the Incidence angle from the Type99 (red line) and the Type15 (orange line) for nearby Fresno CA.
Doing the solar geometry calculations by hand, the Type15 is spot-on, but clearly the Type99 isn't. In both types I am specifying Tracking Mode 3 and both the slope and azimuth of the surface is set as zero for tracking along a N-S axis with no slope.
Is there something I should be doing differently? Or is this an issue within the Type99 source that needs editing?
Thanks for your help!
-Brandon