Vestas this week unveiled its 900kW four-rotor wind turbine concept being assembled in Roskilde, Denmark.

It seems very much like the concept presented by NL Architects with One Architecture and Ton Matton in 2006. Michiel Van Raaij wrote about this project in The Time is Now: Public Art of the Sustainable City, LAGI’s 2010 Design Competition publication.

This vertical axis version is also by NL Architects:

The Vestas version under construction: