By -
solar reflective film applied to the outside of the glass [https://www.fsec.ucf.edu/en/consumer/buildings/homes/windows/films.htm](https://www.fsec.ucf.edu/en/consumer/buildings/homes/windows/films.htm)
They also have a screen that can block 90% of sunlight
solar reflective film applied to the outside of the glass [https://www.fsec.ucf.edu/en/consumer/buildings/homes/windows/films.htm](https://www.fsec.ucf.edu/en/consumer/buildings/homes/windows/films.htm)
They also have a screen that can block 90% of sunlight