Doha Metro Estimated to be Effective in Reducing Climate Impacts by Reducing Dependency on Private Automobiles.
Doha, Qatar
Evaluation of Sustainable Urban Mobility Using Comparative Environmental Life Cycle Assessment: A Case Study of Qatar
Summary Information
At a global level, the release of greenhouse gases (GHGs) plays a substantial role in driving climate change. The transportation sector, including the use of private automobiles, is a significant contributor to GHGs. Qatar stands out with its notable carbon footprint and per capita power consumption, surpassing global averages. In response, the Qatari government has made swift advancements in expanding public transportation alternatives. The objective of this study was to compare the environmental impact of Doha Metro Project, a driverless rapid transit system in Qatar, which was set to begin operation early May of 2019. The study developed comparative life cycle assessment (LCA) models to quantify the energy output and emissions of the automobiles and the metro in Qatar.
METHODOLOGY
The environmental impacts of metropolitan train and passenger car transportation modes were compared per functional unit of 1,000 Passenger Kilometers Traveled (PKT) (about 621 Passenger Miles Traveled (PMT) using a conversion factor of 1 km=0.621 mi) to allow for a better comparison of the two modes within the context of LCA models. An off-the-shelf LCA software was used for the analysis. The environmental impacts of the metropolitan transport system considered in this study were limited to train operations and station power and water use. In contrast, the system boundaries for private automobiles included the unit processes of the automobile fuel consumption during the operations phase. Primary data for the energy, water, and equipment usage of the metropolitan train transport system were collected from Qatar Railways Company. The fuel consumption and equipment use of passenger cars were based on data averages derived from the literature.
FINDINGS
- Considering the environmental impacts of the metropolitan train and automobile systems per 1,000 PKT (621 PMT) in the operations stage, the results showed that use of metro would lead to 78 percent points of reduction in climate change (89 percent to 11 percent, measured as Kg of CO2 equivalent) and 100 percent points reduction in particulate matter (PM) formation (100 percent to 0 percent, measured as KgPM 10 equivalent), compared to automobiles.
- The objective of the metropolitan public transportation system was to decrease traffic by displacing about 190,000 private vehicles daily. Anticipating the environmental benefits of such a reduction, this study estimated that the driverless metro system could significantly reduce annual emissions and resource usage. This includes a reduction of 19.42 kilotons (21.41 kilotons, US) of CO2, 3.15 tonnes (3.47 US tons) of PM 10, 377.17 tonnes (415.76 US tons) of 1,4-dichlorobenzene, 3.02 tonnes (3.33 US tons) of nitrogen, 11.45 tonnes (12.62 US tons) of sulfur dioxide, and a saving of 1.5 cubic meters (396 US Gallons) of water.
