Mitigating the greenhouse gas emissions from urban roadway lighting in China via energy-efficient luminaire adoption and renewable energy utilization

Roadway lighting is critical for creating safe environments for drivers and pedestrians. As China continues to urbanize, the increase in the number of street light facilities will exacerbate the energy and environmental burdens of urban areas. Adopting energy-efficient lighting luminaires and using renewable energy can improve the greenhouse gas (GHG) mitigation potential of urban roadway lighting, contributing to the development of a low-carbon urban environment. In this study, we used a bottom-up approach to estimate GHG mitigation potential associated with replacing current high-pressure sodium (HPS) lamps with light-emitting diode (LED) lamps and deploying solar-wind hybrid street lights, solar street lights, and wind street lights in China. Four classes of urban roads in 662 cities were examined with specific considerations for luminaire specifications, lighting design requirements, and urban-specific availability of solar and wind energy resources. The results showed that the incremental GHG emissions associated with a set of street lights using renewable energy technologies range from 475 to 1631 kg CO(2)e, yielding a GHG payback time of 1.7-7.7 years, which is environmentally cost-effective. The LED-HPS lamp replacement and renewable energy utilization can annually reduce GHG emissions by 21.2 million tons (Mt) of CO(2)e, which is dominated by branch (38%) and trunk roads (31%). East China, especially Jiangsu and Shandong provinces, has the largest GHG mitigation potentials. Dalian, Shanghai, and Tianjin are among the top cities with the greatest GHG mitigation potential. For cities with different administrative levels, prefecture-level cities can achieve a GHG mitigation potential of 56%, approximately 11.9 Mt CO(2)e/year.