A case study in Istanbul E-80: Intelligent speed change at the highway for reducing gas emission

Greenhouses gases (GHGs) are a major problem in the world since they cause warming of the atmosphere and climate change which lead to global warming. Gasoline from transportation systems is the main source of GHGs. Frequent acceleration processes in vehicles cause unnecessary fuel consumption. If unnecessary acceleration is prevented, emission of GHGs will be reduced. In this research, unnecessary acceleration is decreased by changing line speed limit with an intelligent method at the highway. We propose an intelligent speed change (ISC) algorithm, which estimates the number of vehicles waiting in the traffic and calculates a speed limit to decrease unnecessary accelerations. A case study is done to reduce the gas emission at Istanbul E-80 highway with Istanbul Technical University City Transportation Simulation (ITUCiTSim) program. Test section is selected as Şekerpinar-Selimpaşa at one direction. An Intelligent Highway is constructed by placing sensors at access road connections. Traffic on the road is modelled by using the main principles of queueing theory. Information that is acquired by sensors is used in determining new speed limit in an intelligent way. It is demonstrated by simulations that the proposed method leads to a decrease in unnecessary accelerations, which results in a subsequent decrease in emitted GHGs.