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The volume of landfill gas (LFG) produced during municipal solid waste (MSW) decomposition in local landfills has increased rapidly in recent years. To promote circular economy (CE) applications through resource recovery, this article investigates the feasibility of utilizing LFG as a sustainable energy to power data centers (DCs) in Xiamen (China) and evaluates the implications of waste heat reuse on the energy consumption of DC. The objective of this study was to investigate the environmental impacts and economic benefits of this scheme based on a SFC model. With respect to its novelty, LFG is utilized as an energy supply to DCs, while the waste heat generated in the energy production is recovered. The socio-economic benefits generated in this process are also elaborated. It was found that a large number of MSW was completely recycled to generate energy. The LFG enterprise could benefit from energy sale, while the energy satisfied the annual demand for DC power consumption. Utilizing this energy output resulted in the reduction of primary energy and less CO₂ emissions. By reusing the waste heat for domestic heating, the energy efficiency could be improved, while primary energy could be further saved, avoiding more CO₂ emissions. This implies that utilizing LFG output and waste heat to power DCs not only facilitate resource recovery from unused resources to improve energy efficiency and obtain socio-economic benefits, but also promote the digitalization of DCs and sustainable development of urban cities in the framework of CE. [Display omitted] • LFG can be used to power data centers (DCs) in order to promote CE. • The recovery of waste heat from LFG generation reduced CO 2 emission of 8.46 × 108kg. • Within 15 years, 4.97 × 10 10 kg of MSW can generate 4.65 × 109 kW ⋅ h of electricity. • The recovery of waste heat benefited landfill operators and DC firms financially. [ABSTRACT FROM AUTHOR]

• A multi-objective energy-water nexus optimization framework is established. • The provincial economic trade's impact on energy and water stress is quantified. • The economic development level is the key to optimize the resources reallocation. • The rapid trade growth among provinces may aggravate the risk of resource scarcity. With China's vast territory and high regional heterogeneity in the spatial energy and water resources distribution, provincial-level embodied energy (EE) and virtual water (VW) reallocation are critical to regional energy and water recourse management but unfortunately, remain far from completed. In this paper, considering the heterogeneity of energy and water resources endowments among provinces, we constructed a dual objectives optimization framework to minimize national energy stress and water stress. Also, we evaluated the EE and VW flows' synergy impact on mitigating energy and water stress. We found that the spatial resources reallocation has a significant role on mitigating energy and water stress in high-stress regions. The results show that the net energy inflow can increase by 33.5%, and the net water inflow can increase by 42.1% in high-stress regions. The EE and VW flows' impact on mitigating resource stress is affected by the spatial resource endowments' heterogeneity. The flows that have the most positive impact on mitigating regional energy and water stress are Shanxi-Jiangsu and Jiangxi-Shanghai, respectively, while the most negative flows are Jiangsu-Henan and Xinjiang-Heilongjiang, respectively. The EE and VW flows among provinces have synergy in mitigating energy and water stress. Policy makers should not only focus on the local resources' consumption, but on the inter-provincial recourse flow and spatial resource endowments' heterogeneity. Inter-provincial cooperation is recommended, with reducing the scale of EE and VW trade that has negative impact, which can mitigate regional energy and water stress. [ABSTRACT FROM AUTHOR]

• A multi-objective optimization model is established for electric power sector. • Water consumption and carbon emissions from power generation are quantified. • Tradeoffs between water and carbon in electricity mix are evaluated. • Strategies for optimizing electricity mix and tasks distribution are proposed. Electric power sector is a significant water consumer and a major source of carbon emissions in China. Optimizing electricity mix is critical for maintaining a stable energy supply while addressing water stress and carbon emissions associated with power generation. In this study, we developed an optimization model with the dual objectives of mitigating the risk of water scarcity and cutting carbon emissions, by adjusting the electricity mix and power generation tasks of provincial grids. Using the weighted sum method, the optimization of grids is simulated based on a scenario analysis within specified equality and boundary constraints. We quantified the impact of the spatial distribution of thermal power and power generated from clean energies (hydropower, wind power, nuclear power, and solar power) on virtual water consumption and carbon emissions at a provincial level in China. The results suggested that transferring part of power generation tasks from water-deficient areas (e.g., Shandong and Jiangsu) to water-sufficient areas (e.g., Yunnan and Guangdong) could significantly mitigate water scarcity. Water consumption of power generation could be reduced by 34.7% in highly water-deficient areas if a water-prioritized scenario is implemented. Carbon emissions related to power generation could be reduced nationwide under a carbon-prioritized scenario and a water-carbon-balanced scenario. This model could provide a synergistic perspective for improving regional water and carbon performances based on changes in electricity mix. [ABSTRACT FROM AUTHOR]

China is the largest electricity consumers worldwide and the coal-dominated electricity system has led to increasing pressure on climate change and air pollution. Understanding the direct and indirect electricity consumption in China's economy is a prerequisite for proper energy conservation policy formulation. Therefore, this study drew the electricity consumption flows within the domestic supply chain network of China from the on-site electricity consumption to the final demand from 2007 to 2015. Specifically, hotspots of sectors and supply chain paths were identified by adopting power-of-pull analysis and structural path analysis, respectively. We find that Production and Supply of Electricity and Heat was the most critical sector that pulls other sectors' electricity consumption, but its impact has been declining during 2007–2015. The most critical supply chain paths originated from the Manufacture of Nonmetallic Mineral Products and Metal Smelting and Rolling , went through Construction and ultimately ended in capital formation, given that around 40% of the electricity consumption was driven by investment. Moreover, the electricity consumption attributed to each production layer for most sectors were more evenly distributed in 2015 than that in 2007, manifesting that the supply chain relationships for most sectors have become more complex. Our results highlighted the importance of indirect energy management and supply chain engagement in the electricity conservation strategies in China. • Electricity use from production to consumption via supply chains was investigated. • The temporal change of critical sectors' pulling power was shown. • Investment accounted for around 40% of total electricity consumption in China. • Most critical supply chain paths started from investment and ended at metals and non-metal minerals through construction. • Indirect energy and supply chain engagement should be highlighted in policy design. [ABSTRACT FROM AUTHOR]