Motoring into the future

This is one of the fans that operate the air-handling system at this MIT building, which was built in 1949. For the most part, the systems have had only minor upgrades since then. Through this efficiency program, MIT will install variable-speed drive motors, which means that the fans can run at different speeds, rather than at full bore at all times. The speed of the fans that take in outside air will be determined by a set of sensors that will gather data on the humidity of indoor air and carbon dioxide level, which indicates how many people are in a room.