The solar concentrating system is built into the south facing facade and consists of 1,600 heliostatic mirrors that direct the sunlight to a receiver mounted above the mirrors on a cantilevered arm. Molten salt is used as the working fluid to run a steam generator at 500 deg C. The mirrors shade the building partially, but also allow some sun in, which strikes a double curtain wall. Behind the wall is an interstitial greenhouse space reaching all the way to the top of the tower. Air is heated and rises up the 600 m tall chimney and turns the blades for the 2 MW solar updraft turbine.
This incredible design for a skyscraper moves far beyond energy efficiency and sustainable materials. This mixed-use residential and office building could potentially have a negative impact. Although it’s located in a questionable spot without much else around it in terms of public transportation or an urban core, the concept is really fascinating and certainly deserves more study.