Twelve West, a new mixed-use building designed by Zimmer Gunsul Frasca to house its Portland office, as well as street-level retail space, four floors of office space (for ZGF) and 17 floors of residential can also boast the first U.S. installation of a wind turbine array on a high-rise.

The four turbines are 270 ft. above ground, which places them well above the major turbulence caused by the irregularities in the built environment below. An extensive body of research went into their placement and development, as the design team took into account urban topography, weather data, and seasonable variability of wind directions. They then built a large-scale physical model of the building to test it.

The Southwest Windpower horizontal axis turbines are 12 ft. in diameter and feature a passive yaw or rotation system that orients the turbine blades to the wind, and the downwind blade design eliminates the need for a tail or other orienting device. The turbine array is predicted to generate about 10,000 kwh per year. Local and state agencies funded the entire system's cost through renewable energy grants.

Other sustainable features include a 6,000-sq.-ft. terrace and eco-roof that serves to mitigate storm water and reduce the building's heat island effect. Office ventilation mainly is achieved through a combination of an Underfloor Air Distribution System (UFAD) and natural ventilation. The system provides individual control through adjustable diffusers at each workstation. Passive chilled beams will aid in cooling on particularly hot days. Passive chilled beams are perforated metal panels mounted near the ceiling and chilled with cold water tubing.

Twelve West is on track to achieve LEED (NC) Platinum and LEED (CI) Platinum for the ZGF offices.