The new head offices for the Federation of Korean Industries (FKI) are a major new addition to the skyline of Seoul, Korea. The tower features an innovative exterior wall, designed specifically for the project. The building’s unique skin helps reduce internal heating and cooling loads and collects energy through photovoltaic panels that are integrated into the spandrel areas of the southeast and southwest faces. FKI clearly illustrates the advancement in building facades from simple wall systems to high-performance, integrated architectural and engineering design solutions.

FKI’s unique exterior wall system combines maximum access to views, energy efficiency strategies and energy generation technologies. By angling the spandrel panels 30 degrees toward the sun, the amount of energy collected by the photovoltaic panels is maximized. Below the spandrel panels, the vision panels are angled 15 degrees toward the ground, minimizing the amount of direct sun radiation and glare.

The use of building integrated photovoltaic panels (BIPV) was seen as an architecturally appealing way to meet a strict zoning requirement that 5 percent of the building’s energy be created onsite, while the optimization of the panels became a driving factor in developing the architectural expression. The local electric utility company (KEPCO) provided a favorable 5-to-1 buy-back rate for onsite green-energy generation. The payback for the BIPV panels, which would have typically been 30-35 years, was reduced to about seven years, due to these incentives.

As part of the initial design process, an Ecotech model was used to determine the optimal areas for BIPV on an orthogonal building, given the surrounding buildings which partially shade the site. It was determined that BIPV would be best used on the southeast and southwest faces, above Level 14. Not all sides of the building are currently suitable for BIPV; therefore, it was important to design panels that were interchangeable with insulated spandrel panels for maximum flexibility, without a significant change in the symmetry of building expression. The design also allows for the panels to be replaced, as new technology that can take advantage of indirect light becomes available.

The result is a unique folded exterior texture that is both purposeful and visually distinctive. Benefits include a reduction of glare and heat gains from direct sunlight, while maintaining a high level of indirect light. Through most of the day, the building is able to use the geometry of the exterior wall to self-shade the perimeter spaces that would normally be inundated with direct sunlight.

FKI features an expansive rooftop atrium garden that also has custom photovoltaic panels. As with the exterior wall panels, the ideal angle of the panel placement on the roof was studied in detail. Within the limited area of FKI’s roof, it was determined that a 10-degree angle allowed for more panels to be installed closer together, minimizing the effect of the panels casting shadows on each other and ultimately producing more solar energy for the building.

The sculptural podium piece’s amenities, available for public use, include a banquet hall, a central restaurant and a conference center. Site orientation was altered during the course of design, sliding the tower to the west. This opened up more site frontage and allowed the podium to be closer to the street, giving it a presence it would not have had if located behind the tower, and allows more space for outdoor public landscaped courtyards.