Photos: Evan Rosenberg/Metro
You’re standing on a subway station platform, waiting for the train. Suddenly, the wind picks up. You know this means the train is coming. Many of you may also know why there’s wind: it’s displaced air being pushed through the tunnel by the fast moving train. And some of you — including Tom Kefalas, Metro Environmental Compliance and Services Manager — may have wondered if there was a way all that generated wind could be utilized as a renewable energy source.
Thanks to Tom Kefalas and Cris Liban, Director of Metro Environmental Compliance Services, we now know the answer is yes. From August through September 2013, Metro conducted a one-month pilot program to see if wind energy could safely and effectively be captured and used. The project involved working with engineers from WWT Tunnel, LLC, a subcontractor to Arcadis U.S., to create and install a unique 10-foot multi-blade mass airflow collection equipment (MACE) in the Red Line tunnel. To our knowledge, this is the first time a transit agency has tested the effect of having a wind turbine in a subway tunnel.
The MACE was installed between the North Hollywood and Universal City stations, a segment of the tunnel that sees trains reaching speeds of up to 70 mph. Each time a train left the station, the MACE fan blades would start spinning, thus capturing energy up to a minute before the train actually passed by. The blades would continue to spin up to 2 minutes after the train passed, and exceeded 1,070 revolutions per minute (RPM). The amount of electricity produced by these train initiated events was nearly double the amount that had originally been anticipated.