DailyTech

"Simone Giostra & Partners architectural firm have created a video wall called Greenpix that requires no power to operate. Greenpix is the massive LED video wall façade of the Xicui entertainment complex in Beijing, China. The complex is located near the site of the 2008 Olympic Games and is the largest color LED display in the world.

More impressive than the façade is that the entire display is 100 percent self-powered. During the day the panels harvest solar energy that is in turn used to generate the static and moving images on the LED displays at night. Chinese officials will display specially commissioned programs and video from artists from around the world during the Games this year.

Chinese representatives who unveiled the display herald it as a beacon for what green technology can accomplish, while still pushing the boundaries of what's technically feasible.  No comment was made on how long the display could operate on a single-day's charge, however.

Another company called Arup developed a new technology for laminating photovoltaic cells into a glass curtain for the project. The photovoltaic cells are laminated into the Greenpix screen in varying densities to increase the performance of the building. The changes in density of the panels allow natural light in when required and reduce the heat that enters the building.

The backlighting for the LED panels is provided by circular florescent lighting spaced every 900mm x 900mm. Each of the glass panels used in the wall measures 890mm x 890mm."