Energy Conservation at Traffic Signals at Off-Peak Hours

Stopping unnecessarily at a traffic signal, idling and accelerating again can be energy wasting. The potential impact of switching traffic lights to their flashing amber operating mode during off-peak hours on energy saving and on safety is examined. An experimentally controlled comparison was made of traffic behaviour at the same intersections and during similar hours under two modes of operation. The results showed that at low traffic volumes (up to 600 v/hr), there was a significant energy saving during the flashing amber mode, due to the reduced number of stopped vehicles and shorter delay times without any change in traffic safety.