Green total-factor energy efficiency and its convergence of industrial sub-sectors in China.

Existing literature ignores to consider multiple types of pollutants when analyzing energy efficiency and its convergence. Under this background, using SuperSBM-GML model, the improved entropy method, and convergence model, this paper calculates the green total-factor energy efficiency and its evolution trend of 35 China's industrial sub-sectors considering multiple pollutants, and analyzes its convergence. The results indicate that the average score of industrial green total-factor energy efficiency is low, and there are significant differences among sub-sectors: "Utilization of waste resources" is the highest, while "Manufacture of paper and paper products" is the lowest. The green total-factor energy efficiency shows an overall upward trend from 2006 to 2021, the main driving force comes from technological progress, but numerous sub-sectors have not sufficiently caught up with existing cutting-edge technologies. Specifically, the growth rate of green total-factor energy efficiency in high-energy-consumption sub-sectors is higher than low-to-medium-energy-consumption sub-sectors. There are both σ-convergence and ß-convergence in low-to-medium-energy-consumption group, indicating that development of sub-sectors is stable and outstanding. Nevertheless, the high-energy-consumption group only exhibits conditional ß-convergence, revealing an imbalance in energy efficiency development. Consequently, formulating the benchmark level of energy efficiency and developing energy efficiency "leader" system are suggested for low-to-medium and high-energy-consumption sub-sectors, respectively.

The impact of ultra-high voltage projects on carbon emissions in China.

The inter-regional ultra-high voltage (UHV) projects are crucial for power systems. Carbon emissions associated with the power sector cannot be ignored. In this paper, based on the panel data of 198 prefecture-level cities in China from 2009 to 2019, a multi-period difference-in-difference model is developed for the first time to examine the impact of UHV projects on carbon emissions. Empirical results show that UHV projects increase overall carbon emissions. This impact can also be achieved through the mechanisms of the scale of power generation and the level of economic development. Heterogeneity research demonstrates that the carbon emissions issue of UHV projects is more significant in cities with low levels of economic development and a large proportion of secondary industries. Extensibility research shows that UHV projects have a more significant impact on carbon emissions in power-sending cities than that in power-receiving cities. The more clean power the UHV transmission lines transmit, the less impact on carbon emissions. This study not only enhances our understanding about the impact of UHV projects on carbon emissions, but also provides inspiration for the low-carbon pathway transition.

Modelling natural gas, renewables-sourced electricity, and ICT trade on economic growth and environment: evidence from top natural gas producers in Africa.

Addressing extensive global goals including growing energy-sourced electricity and advancing sustainable development plans strongly depends on natural gas as a transition fuel to renewable forms of energy. Therefore, by using pooled, random, and fixed-effects models, the current study investigates the effects of electricity sourced from natural gas (ENG), renewable energy (RE), and trade in information and communication technologies (ICTs) on economic growth and carbon dioxide (CO2) emissions in Africa's top three natural gas producers, Algeria, Egypt, and Nigeria, from 1990 to 2020. The findings indicate that CO2, ENG, ICT trade, and urbanization (UP) are all strongly and positively correlated to economic progress, with the exception of RE, which has an insignificant influence. For the environment, data indicate that RE and GDP degrade the environment while ENG and ICT trade boost it. The causality results that ENG and RE cause both economic growth and CO2 emissions. Based on these empirical results, it is recommended that policymakers should step up their efforts to usage natural gas as a transition fuel to renewable energy sources and acknowledge the advantages of the significant contribution that green ICT trade can make to economic advancement and a clean environment.

Technological roadmap towards optimal decarbonization development of China's iron and steel industry.

China's iron and steel (IS) industry contributes approximately 16 % of the nation's total CO2 emissions. This study evaluates the environmental impact of each step in the production process based on the life cycle assessment method. It then explores potential deep decarbonisation pathways, developing an integrated dynamic model to meet the carbon neutrality target. The results reveal three primary findings. (1) In 2020, the blast furnace-basic oxygen furnace contributed significantly to the global warming potential -1.77 E-8 kg CO2 equivalents per year (eq/yr) higher than the electric arc furnace-and the blast furnace process makes the largest contribution in ironmaking (8.9E-9 kg CO2 eq/yr). (2) Converter negative energy steelmaking technology has the highest energy savings at 39.07 million tons of coal equivalent (Mtce) and an emissions-reduction potential of 72.01 Mt. Its mitigation cost is 69 CNY/t CO2, followed by thick-layer sintering (30.21 Mtce, 61.21 Mt. and 70 CNY/t CO2) and the application of dry vacuum system for molten steel degassing circulation (26.17 Mtce, 56.03 Mt. and 102 CNY/t CO2). (3) Technological improvement could significantly impact the IS industry, reducing CO2 emissions through production structure improvement, technological development and ultra-low emissions technology, from 789 Mt. in a business-as-usual scenario to 516 Mt., 261 Mt. and 157 Mt. in 2060, respectively.

Research on the coordination of energy in China's economic growth.

This study uses the improved Cobb-Douglas two-factor production function model to explore the potential relationship between economic growth and energy consumption through the multiple co-integration test on the panel data of China from 1985 to 2018. The results show that there is a positive long-term balance between energy consumption and economic growth: economic growth of 1%, total energy consumption growth of 1.53%, which means that economic growth needs higher energy support in the former short term. At the same time, the error correction term will converge energy consumption to a long-term equilibrium state with an adjustment intensity of 134.59%. From the results of variance decomposition, we can also see that as the number of periods increases, the part of real economic growth explained by energy consumption gradually increases.

Unveiling land footprint of solar power: A pilot solar tower project in China.

Land occupation by solar power installations has become a rising concern that may cause adverse impacts on natural ecosystems and biodiversity. Existing studies mainly adopt a local perspective to view land use requirements of solar power and forget that the solar-based electricity system is subordinate to the macro economy and nourished by the material, machinery and service support by various economic sectors. To manifest a key aspect of the footprint of solar power on land resources, this study uncovered the extensive industrial land use initiated by the infrastructure of a representative pilot solar-based electricity plant using a systems perspective. The results in this study show that in magnitude, land footprint by the infrastructure of the pilot solar plant amounts to three times as much as the onsite land area. Also, the land footprint calculated is revealed as one order of magnitude larger than a previous finding that includes primary materials only, and four to seven times higher than the onsite land use by coal-based electricity plants. The outcome implies that existing environmental management policies need to be re-evaluated by putting enough emphasis on the land displacement by solar power systems along the production chain.