Abstract:
Two pre-timed signalized traffic intersections in Islamabad (Pakistan) were studied to estimate idling fuel losses and corresponding emissions.
In the study, idling fuel consumption tests were carried out using an onboard vehicle fuel flow rate measuring device known as OBD II for four (4) categories of vehicles representing the traffic mix of Islamabad. Four test vehicles from each category were tested to estimate the fuel consumed. The 4 test vehicle categories included different engine capacity which are 660 CC, 800 CC, 1300 CC, and 1800 CC. To validate the results from the OBD II device, fuel consumption was measured manually by filling the fuel tank to its maximum capacity and keeping the vehicle idling for ten minutes, and then refill the fuel tank measuring the fuel consumed with a measuring cylinder. Vehicular exhaust gases (CO, CO2, SO2, Nox, HC, and PM) emissions were estimated using fuel-based emission inventory.
The results indicated that hourly 42.282 liters of petrol at Agha Shahi Avenue G-8 intersection and 34.710 liters of petrol at E-11 intersection losses occur due to the idling of motor vehicles at these intersections which is equivalent to a loss of 4788.014 and 3930.560 rupees hourly respectively. The methodology adopted to estimate the fuel losses occurring during idling of vehicles and the emissions taking place at the signalized intersections has been discussed. Finally, remedial and medication measures to reduce idling fuel consumption and corresponding emissions at these signalized intersections have been suggested.
