For pure solar heat gain and shadow studies, both are excellent. DIALux is free and arguably has better integration with BIM software. Helioscope is faster for quick photometric layouts.
A: Yes, it's excellent. Stellarium accurately calculates and displays the sun's position, elevation, and apparent diameter for any time and location, making it an ideal planning tool. helioscope software free
After analyzing user experiences from Solar Builder Magazine forums and Reddit’s r/solar, the winning approach is: For pure solar heat gain and shadow studies,
on how to sign up for the student trial, or would you like a comparison of free alternatives to HelioScope? helioscope software free
To access the full feature set of HelioScope without paying immediately: