Uncovering the Carbon Emission Intensity and Potentials of Shenzhen Metro Operation Phase

The huge energy consumption of metro operation has become great challenge facing by urban public transportation sector to achieve low-carbon development. Take Shenzhen as an example, this study has made efforts to quantify the energy consumption and carbon emission intensity by using Life Cycle Assessment approach, and then evaluate reduction actions. Comparable analysis between subway and other public transportation modes has also been conducted. Results show that the annual carbon emissions from metro's operation phase in Shenzhen city increased from 63,000 t CO2e in 2005 to 1.3 Mt CO2e in 2021, and the historical accumulated carbon emissions are 9.5 Mt CO2e. The unit operating mileage, unit station area and per capita carbon emission intensity were 2.1 kg CO2e/km, 132.5 kg CO2e/ m2, and 0.6 kg CO2e per capita (2016-2020), respectively. To continually promote the low carbon operation of subway, the cumulative carbon savings could reach 0.1 Mt CO2e (2022–2035)