Plastics are essential to human activities but also drive climate burdens and global pollution from energy-intensive material production and waste treatment. This study proposes and evaluates sustainable technology roadmaps under energy transitions to non-fossils to decarbonize the plastic life cycle and mitigate pollution across 202 global countries from 2024 to 2060. The results show that substituting plastic use, combined with advanced chemical recycling and carbon capture utilization powered by renewables, minimizes waste generation and pollution. In North America and Europe, replacing 56.7 % of plastics with glass, metal, and biodegradable alternatives coupled with chemical recycling can achieve zero annual waste by 2040 or 2035 with biomass-powered carbon capture and utilization. In African and Southeast Asian countries, this net-zero waste goal will be delayed to 2055 due to excessive plastic waste from global trade imports. Strategies including a 50 % cross-border tariff increment on plastic waste export and promoting alternative material use can reduce 87.45 % of global waste trade volume and surpluses to developed countries. This study advances the existing local and global plastic pollution mitigation strategies integrating energy decarbonization and transition to strengthen the United Nations Global Plastic Treaty towards minimum plastic pollution.

The lack of clarity and uncertainty about hydrogen's role, demand, applications, and economics has been a barrier to the development of the hydrogen economy. In this paper, an optimisation model for the integrated planning and operation of hydrogen and electricity systems is presented to identify the role of hydrogen technologies and linepack in decarbonising energy systems, improving system flexibility, and enhancing energy system security and resilience against extreme weather events. The studies are conducted on Great Britain's (GB) 2050 net-zero electricity and gas transmission systems to analyse the hydrogen transport and capacity requirements within the existing infrastructure under different scenarios. This includes sensitivities on the level of flexibility, high gas prices, hydrogen production mixes, enabled reversibility of electrolysers, electricity generation cost, and hydrogen storage facilities. In all sensitivity scenarios, efficient hydrogen transport within the existing infrastructure is enabled by the optimal allocation of green and blue hydrogen sources, distributed storage facilities, and the intra-day flexibility provided by linepack. The findings highlight that increased renewable deployment transfers intermittency to the hydrogen network, requiring greater linepack flexibility compared to the current paradigm (up to 83%). Furthermore, the necessity of synergy between different gas and electricity systems components in providing flexibility, security, and resilience is quantified.

As the enthusiasm for electric vehicles passes the range anxiety and other tests, large-scale transportation electrification becomes a prominent topic in research and policy discussions. In consequence, the public attention has shifted upstream and holistically towards the integration of large-scale transportation electrification to power systems. This paper proposes a method to identify bottlenecks in power transmission systems to accommodate large-scale and stochastic electric vehicles charging demands. First, a distributionally robust chance-constrained direct current optimal power flow model is developed to quantify the impacts of stochastic electric vehicles charging demands. Subsequently, an agent-based model with the trip-chain method is applied to obtain the spatiotemporal distributions of electric vehicles charging demands for both light-duty electric vehicles and medium and heavy-duty electric vehicles. The first two moments of those distributions are extracted to build an ambiguity set of electric vehicles charging demands. Finally, a 121-bus synthetic transmission network for New York State power systems is used to validate the future transportation electrification in New York State from 2025 to 2035. Results show that the large-scale transportation electrification in New York State will account for approximately 13.33 % to 16.79 % of the total load demand by 2035. The transmission capacity is the major bottleneck in supporting New York State to achieve its transportation electrification. To resolve the bottlenecks, we explore some possible solutions, such as transmission capacity expansion and distributed energy resources investment. Wind power shows an advantage over solar energy in terms of total operational costs due to better peak alignment between wind power and electric vehicles charging demand.