Scenario analysis of energy transition in eastern coastal metropolitan regions of China

Ratifying the Paris Treaty in 2016, China committed itself to the global climate target to keep the global temperature increase well below 2 °C. With an expected accelerated urbanization process until 2050 and high industrial activity, China faces big challenges in achieving an environmentally friendly energy supply and, in particular, mitigating CO2 emissions. Especially the eastern coastal metropolitan regions are playing an important role in decision making and implementation processes on the way to a decarbonized economy and society. The national and provincial administrations in China have already started to address the issue of energy transition towards a low-carbon system, but long-term integrated transition plans are not yet available on the regional level. In this thesis I therefore focus on two metropolitan regions of eastern China (Beijing-Tianjin-Hebei region in the north and Yangtze River Delta region in the south) with high energy consumption and related CO2 emissions. The analysis starts with the main challenges the regions are facing with regard to energy transition and the existing energy policy plans on different administrative levels. The review shows that the current policies are rather short-term driven and weak regarding sector coupling and regional integration. As in China economic activities and population are concentrated in the eastern coastal regions, while renewable energy resources are concentrated in the western inland regions, specific regional challenges and conditions must be taken into account when modelling long-term integrated energy systems. In my thesis, three scenarios are therefore constructed, namely the Current Policy Scenario (CPS), the Natural Gas & Nuclear Scenario (NGNS) and the Renewable & Import Scenario (RIS), which are based on a normative storyline-and-modelling approach. The scenario analysis shows that regional CO2 emissions could be significantly reduced in all sectors by adjusting the economic structure, implementing efficiency measures, replacing coal and oil, and multi-sector electrification supported by enhanced electricity import capacities. Due to the massive electrification, CO2 emissions in both regions will remain mainly from gas combustion in the power sector. The scenario comparison provides insights into requirements of the energy transition regarding the implementation of new technologies and their effects. Thus, it can serve as a basis for deriving political strategies from long-term perspective to further shape the transition process in metropolitan regions from both the supply and the demand side. In order to analyze import options from renewable electricity for the metropolitan regions, a case study focusses on the Beijing-Tianjin-Hebei region with Inner Mongolia as the supply region. Main research questions are how a predominantly renewable energy power supply can be implemented and which shares of locally available or imported renewable resources can be used. Based on the Renewable & Import Scenario (RIS), the future power systems are further analyzed applying the REMix energy system model developed at DLR, which uses a cost-minimizing algorithm. Temporally and spatially resolved load profiles and variable wind and solar power generation are the most important input data. A sensitivity analysis for key parameters provides important information on the robustness and interactions in modelling. The results provide insights into the infrastructural needs such as storage and grid expansion. The above model-based scenario analysis depends on a number of key assumptions and leads to conclusions mainly from a system perspective. It demonstrates that the eastern metropolitan regions could largely be supplied with imported electricity from onshore wind and solar power plants in the west at reasonable costs. Therefore, regional coordination and governance, the establishment of energy and carbon markets are crucial factors for successful energy transition processes at different administrative levels. Regionally integrated modelling of the energy system can support decision making in the implementation of new technologies and infrastructure options for metropolitan regions to achieve the long-term climate targets