Greenhouse gas emissions from key infrastructure sectors in larger and smaller Chinese cities: method development and benchmarking

With massive urbanization and infrastructure investments occurring in China, understanding GHG emissions from infrastructure use in small and large Chinese cities with different administrative levels is important for building future low-carbon cities. This paper identifies diverse data sources to assess GHG emission from community-wide infrastructure footprints (CIF) in four Chinese cities of varying population (1 to 20 million people) and administrative levels: Yixing, Qinhuangdao, Xiamen and Beijing. CIF addresses seven infrastructure sectors providing energy (fuels/coal), electricity, water supply and wastewater treatment, transportation, municipal waste management, construction materials, and food to support urban activities. Industrial energy use dominates the infrastructure GHG CIF in all four cities, ranging from 76% of total CIF in Yixing to 30% in Beijing, followed by residential energy use (6–13%), transportation (4–12%), commercial energy use (2–25%), food (6–11%), cement use (3–8%) and water (about 1%), thereby identifying priorities for low-carbon infrastructure development. Trans-boundary footprint contributions ranged from 31% (Beijing) to 8% (Qinhuangdao), indicating that supply chains to cities are important. GHGs from energy use are dominated by electricity (35–45%) and non-electricity coal use (30–50%). The authors demonstrate that disaggregated infrastructure use-efficiency metrics in each infrastructure sector provide useful baseline performance data for comparing diverse cities.