A prismatic outer layer reflects solar radiation in summer months when the sun is higher angle > 40°, reflecting solar heat gain.
In the winter months, when the sun is lower in the sky > 35°, the Prism allows more solar gain in winter or Heating Degree Days when it is most needed.
In affect the Prism gives GlassX a variable G-value or Solar-Heat-Gain-Coefficient for seasonal conditions.

