Pane of Glass

Amazing IoT #8: Solar Windows (not Panels!)

#IoT for Good, Amazing IoT
  • Photo Credit: Yimu Zhao / MSU

A handful of startups are heading toward a new window of opportunity: solar powered windows. If you think about all of the windows in the world – Manhattan alone has 10.7 million windows – creating a window that allows businesses to save on energy costs would be breaking into an almost unimaginably huge market.

Solar powered windows sound conceptually like an oxymoron: Solar panels absorb and reflect light while windows let light through. Various startups have proposed different solutions to this issue which, at its heart, is a serious one. The company Solaria, uses thin strips of photovoltaics on already existing glass, making windows appear pin-striped. Another startup called Oxford Photvoltaics uses perovskite – an oxide used for superconductors – in order to capture solar energy. Their windows are tinted colors such as orange and red. Believing using tinted or colored windows is “like working in a disco” competitor Richard Lunt and his team at Michigan State University created solar panel windows with a new method called Transparent Luminescent Solar Concentrator (TSLC). This method has the photovoltaic strips on the edge of the glass, allowing the window to be more transparent than the other two.

The setback of Lunt’s design is that it only absorbs 1% of light. Regular solar panels absorb up to 15%, and SolarWindows and Oxford Photovoltaics can absorb closer to 8-10%.  Even with these low absorption rates, solar powered windows can make a huge impact on energy reduction, and companies that purchase these windows can find a return of investment within a few years.