Known for its street grids, copious parks and legendary architecture, Chicago is often touted as one of the best planned urban areas in the U.S. From now until November 20, visitors to the Chicago Architecture Fountation will be able to see how the city has grown since the early 20th century at the Chicago Model City exhibit.

The exhibit consists of a detailed 900-sq ft replica of Chicago's down-town, designed to demonstrate how various facets of the city--including its transportation networks and public parks--were created and what impact they've had on residents. Lightswitch Architectural provided the exhibit lighting, which simulates the light patterns of June 21, 2009--the longest day of the year--every 15 minutes. The team used color-changing LEDs to reproduce the full specturm of daylight from direct sunlight to the sky's bluish-colored "fill" light.

Using only 2600 watts per day, the exhibit lighting saves 80% in energy costs compared to a traditional theatrical lighting system, echoing another tenant of Chicago's modern-day urban planners: sustainable design. Visit www.architecture.org/exhibitions for more details.