Willis Tower harvests sun energy

March 22, 2011 3:27:20 PM PDT
The Willis Tower could be turned into a giant vertical solar farm if an experiment there is successful.

As part of a pilot project started in November, a few windows on the 56th floor have been treated to harvest energy from the sun.

The company that treated the windows claims each produces the same amount of energy as a conventional solar panel. It lets daylight in but cuts heat.

If successful, more windows on the building will be treated.