how is the insulation of this new glass, great if it saves emmisions on the production side, but if it lets all the heat in my house fly outside it won't save a thing.
You get insulation gains from double | triple paning along with low-e coatings.
https://engext.ksu.edu/buildingenvelope/windowsanddoors
For those not into defenestration, See:
National Fenestration Rating Council https://www.nfrc.org/