Facing green trade barriers from developed nations, particularly the EU, based on product carbon footprints, China’s renewable energy industries confront significant challenges in transitioning towards sustainability and low carbon emissions. This study delves into the carbon footprint of China’s renewable infrastructure, evaluating wind turbines, photovoltaic (PV) panels, and lithium batteries across varied decarbonization scenarios, emphasizing both production and international trade transportation. The initial findings for 2022 indicate baseline carbon footprints of 990,701 kg CO₂-eq/MW for wind turbines, 2994.97 kg CO₂-eq/kWp for PV panels, and 67.53 kg CO₂-eq/kWh for batteries. Projections for 2050 suggest that decarbonization advancements could slash these footprints by up to 36.1% for wind turbines, 76.7% for PV panels, and 72.5% for batteries, closely mirroring the EU’s 2050 low-carbon benchmarks. Considerable carbon footprints from both domestic and international transportation have been quantified, underscoring the importance of logistic decarbonization. Based on these results, it is concluded that China’s steadfast commitment to a sustainable and climate-ambitious development path can provide globally competitive, low-carbon renewable infrastructure after 2030. The study advocates for a collaborative approach to product decarbonization across international trade, as opposed to erecting barriers, to effectively contribute to global climate objectives.

A validated standard k-ε model was used to investigate the effects of ground heating on ventilation and pollutant transport in a three-dimensional (3D) street canyon. Air entered the street canyon from the upper regions of side surfaces and most areas of the top surface and left from the lower regions of side surfaces. Ground heating enhanced the mean flow, ventilation, and turbulence, and facilitated pollutant reduction inside street canyons. The transport patterns in a street canyon that included a pollutant source (PSC) and a target street canyon downstream (TSC) were different. The pollutant did not enter the PSC, and turbulent diffusion dominated pollutant outflow at all boundaries. The pollutant entered the TSC from most regions of the side surfaces and exited from lower regions of the side surfaces and the entire top surface. Air convection dominated pollutant transport at the side surfaces, and its contribution increased significantly with ground temperature; Furthermore, turbulent diffusion dominated pollutant outflow for the top surface, and its contribution increased slightly with ground heating. As revealed by an analysis of both the total pollutant flow rates and air flow rates, although air/pollutant exchange between the TSC and outer space occurred primarily through the side surfaces, the increase in air inflow from the top surface reduced the pollutant concentration inside the street canyon when the ground temperature increased. The top surface played a major role in improving air quality in a 3D environment with ground dispersion. This study supplied valuable suggestions for urban planning strategies. The analyzing method used in this research is helpful for the pollutant transport investigations in urban areas.