Triple glaze windows / Discussions

I couldn't see the answer in a search - apologies if this has already been covered. If I know that at the winter solstice the sun will be at an elevation of 20 degrees, my south facing (northern hemisphere) glazing is 4 metres high (bottom to top of windows) - then what is furthest point the sun will reach to into the...

...triple glaze Argon filled windows be appropriate without the Low E coating?  The Low E coating does reduce the solar gain even if you choose a coating designed for the northern climate.  (I am in Ontario 44 degrees north).  My application would have 5x5 ft fixed windows with 5x2 foot awning style windows below and abov...