Late last week, my architectural office had a visit from a couple of representatives from the manufacturer, Sage Glass. In addition to having a display sample of the material which they showed (giving me a chance to see this material in person for the first time), they also had some information about what is forthcoming with electrochromic glass.

The present configuration for electrochromic glass is binary control; it's either on or off (though it takes it a few minutes to go from one to the other). However, the company anticipates that, by 2008, they will be providing adjustable controls that will let users set an intermediate level of shading with the glass. It will be possible to block a portion of the light, and make more gradual transitions than are now possible.

They also note that they are working on developing photovoltaic power for their windows.

Can SageGlass be powered with photovoltaics (solar cells)?

Yes, PV-powered SageGlass IGUs are under development. Because of their low DC voltage and power consumption, and the obvious complementary relationship between the amount of sunlight available and the level of tinting required to modulate it, SageGlass products are excellent candidates for PV power.

This is still an expensive product. It currently costs around $100 per square foot for the glass. But, as demand increases and they are able to increase their production level, they are expecting the prices on this material to come down in the coming years.

Link: Sage Glass