Former Sears Tower turns to high rise solar

In 1974 it was once the tallest building in the world. Now the 108-storey Willis Tower (formerly the Sears Tower) in Chicago is getting set to become a massive vertical solar power generating plant, with plans firmly afoot to install a new type of photovoltaic glass on the south side of the 56th floor as part of a pilot solar electric glass project—a collaboration between the Willis Tower owner and solar manufacturer Pythagoras Solar.

The new glass uses a building integrated photovoltaic (BIPV) solution that has the potential to expand to a surface area that allows for over two megawatts of solar power generation—that’s about the same as a 10-acre field of solar panels. describes the glass as “..a clever hybrid technology that lays typical monocrystalline silicon solar cell horizontally between two layers of glass to form an individual tile. An internal plastic reflective prism directs angled sunlight onto the solar cells but allows diffuse daylight and horizontal light through. Think of it as a louvered shade which allows for views but cuts out the harsh direct sun”.

Pythagoras Solar says the vertical glass system can generate the same amount of energy as regular rooftop solar systems, and has an architectural design that can “ increase real estate value and advance Net Zero Energy Buildings”.