The development of a carbon footprint model for the calculation of GHG emissions from highways: the case of Egnatia Odos in Greece

Abstract

Global transport demand is increasing and the associated emissions of GHGs are becoming a key factor in the environmental planning of networks and the actual operational management stage. We describe the development of a novel methodology for the calculation of the carbon footprint of a major motorway (Egnatia Odos) in Northern Greece. Total GHG emissions were calculated for 2014 as the base year, from all corporate activities, including stationary and mobile combustion, fugitive gases, purchased electricity, personnel travel, waste disposal and contractor (third party) emissions. End user vehicle emissions constitute a significant part of the carbon footprint and are estimated from annual traffic data supplied by Egnatia Odos S.A., combined with emission factors extracted from the TREMOVE model, for different vehicle categories and fuel types. The emissions model developed uses additional input data, concerning fuel and electricity consumption, fugitive gases from a/c equipment, personnel commuting and travel, waste disposal, and contractor data, also provided by Egnatia Odos S.A., for the calculation of direct and indirect GHG emissions for all three Scopes of the GHG Protocol. The final product was developed in the form of a specialized electronic platform, which is user-friendly and can be updated with the most recent input data available, in order to be used by highways’ personnel for the calculation of their carbon footprint in future years. The overall carbon footprint of Egnatia Odos S.A. in 2014 has been estimated at 770 ktCO2e, with 91% of emissions sourced by the end user category (i.e. vehicle emissions).