Eric Richardson [Flickr]

A row of aluminum scrims stand open on the Los Angeles street side of the Caltrans building.

DOWNTOWN LOS ANGELES — On Sunday afternoon I was bicycling past the Caltrans building when I heard an odd sound. Looking up, I saw a row of aluminum scrim panels that had been open start to close one by one. Though I was familiar with the building's design, I believe it's the first time I'd actually seen the panels in action.

The Caltrans building's east and west faces are covered in these aluminum scrim panels. Many are decorative, but roughly 2,000 of them open and close. They're controlled by a computer, which changes their position based on sun and temperature sensors. It's a high tech tool that was part of cutting the building's cooling costs.