Light and power

by March 27, 2011

A quick glance at the all-window exteriors of modern office buildings seems to offer little hope for the application of solar power cells anywhere but on rooftops, which comprise but a small proportion of a given tower’s total surface area. Israeli venture Pythagoras Solar is changing this equation, however, having developed standard-format double pane windows that use embedded photovoltaic devices to generate power–the latest example of an increasingly flexible architectural approach known as building-integrated photovoltaics (BIPV). In a pilot project beginning this past November, Pythagoras installed its windows on the 56th floor of the iconic Willis Tower in Chicago (formerly known as the Sears Tower), and the company estimates that applying the technology to the rest of the building would enable the generation of two megawatts of electricity. Here’s a cutaway of the company’s window design: