The Lewis Center is considered as one of the most important green building in the last decade. Constructed in 1999, the Lewis Center is one of the first buildings to produce its own energy. The famous sustainability architect William McDonough designed this center. The buildings infrastructure has unique features ahead of times. Such features include producing its own energy such as natural resources and geothermal heating, and having daylighting and light sensors, mainlined indoor air and triple panel argon filled windows.