Traffic congestion is a problem related not only to traffic characteristics but also to several other factors which are of growing concern to the society. Traffic delays lead to increased fuel consumption and there by increased energy loss. This research is aimed at using energy loss as a parameter to measure the effect of traffic congestion on a road segment or transportation network. Data for the year of 2012 for the City of Charlotte was considered for research and analysis. The data was taken from INRIX which contains travel time information for every day of the year and for every minute of the day. Three different times of the day were considered for research. They are: morning peak hour (8 am - 9 am), off-peak hour (12 pm - 1 pm) and evening peak hour (5 pm - 6 pm). The variations in energy loss patterns on a weekday and a weekend day were examined. Mathematical equations were used to compute the energy losses from delay. Geographic Information Systems (GIS) was explicitly used in this research not only as a query tool but also to generate maps to evaluate the energy loss.Energy loss maps at link level and Voronoi maps were generated in GIS environment to examine spatial variations in energy loss. The energy loss maps at link level were used to visually represent energy losses on the road network and also to generate Voronoi maps. These maps have the potential to predict energy loss for links with missing data.Corridors such as Brookshire freeway and I-485 were observed to experience the highest energy loss or traffic congestion during most of the times considered in this research. The energy losses were higher towards the downtown/uptown area and decreased as the distance from the downtown/uptown area increased. The energy loss due to recurring and non-recurring congestion was observed to be the highest during evening peak hour on a weekday and off-peak hour on a weekend, respectively.
