Emission Reduction Policies Research Articles

The Optuna–LightGBM–XGBoost Model: A Novel Approach for Estimating Carbon Emissions Based on the Electricity–Carbon Nexus

With the challenge posed by global warming, accurately estimating and managing carbon emissions becomes a key step for businesses, especially power generation companies, to reduce their environmental impact. Optuna–LightGBM–XGBoost, a novel power and carbon emission relationship model that aims to improve the efficiency of carbon emission monitoring and estimation for power generation companies, is proposed in this paper. Deeply exploring the intrinsic link between power production data and carbon emissions, this model paves a new path for “measuring carbon through electricity”, in contrast to the emission factor method commonly used in China. Unit data from power generation companies are processed into structured tabular data, and a parallel processing framework is constructed with LightGBM and XGBoost, and optimized with the Optuna algorithm. The multilayer perceptron (MLP) is used to fuse features to enhance prediction accuracy by capturing characters that the individual models cannot detect. Simulation results show that Optuna–LightGBM–XGBoost can achieve better performance compared to existing methods. The mean absolute error (MAE), mean squared error (MSE), mean absolute percentage error (MAPE), and coefficient of determination (R2) of the model are 0.652, 0.939, 0.136, and 0.994, respectively. This not only helps governments and enterprises to develop more scientific and reasonable emission reduction strategies and policies, but also lays a solid foundation for achieving global carbon neutrality goals.

CHANGES IN THE MACROENVIRONMENT AND NEW THREATS TO FARMS

In the context of agriculture, numerous significant long-term trends are emerging. Some of these pose threats to farm operations. They can be categorized as threats related to pressure to achieve climate and environmental targets under emission reduction, animal welfare and biodiversity policy, climate changes, structural changes in the farm environment, increasing technological pressure, changes in consumption patterns and unequal conditions of competition in international markets. This study aimed to identify phenomena perceived as threats to agricultural activities and the general mechanisms of their impact on agricultural farms. It is prepared based on a literature review. It was found that the effect of some threats can be mitigated through proper farming practices and increasing production scale. Other threats, including those arising from enforced climate and agricultural policies, have consequences that necessitate economic support for farms or compensation for losses, for example, through subsidies. Insurance may be useful only for protection against well-known threats of measurable risk. One can state that currently published research results still insufficiently recognize how emerging threats alter the outcomes of agricultural farms, what strategies farmers adopt, and which of these are effective for particular production types and given production scales.

Decomposition, decoupling and dynamic prediction of carbon emissions from city-level building operations: a case study of the Yangtze River Delta

Reducing carbon emissions in the building sector is crucial to achieving carbon peak and carbon neutrality goals. Identifying the influencing factors of carbon emissions from building operations at the city level and predicting carbon peaks is of great significance for developing locally adapted policies. This article examines the spatial and temporal trends of carbon emissions at the building operation stage in the Yangtze River Delta (YRD) region over the last 15 years. This article analyzes the driving factors at a city level using the GDIM method and evaluates the decoupling status of income growth and carbon emissions with the GDIM-based decoupling model. The peak time and peak value of operational carbon emissions in the YRD region are predicted through a combination of scenario analysis and the Monte Carlo method. The research shows that: (1) the total carbon emissions from the building operational stage in the YRD region increased by 163.63%, of residents’ disposable income and energy consumption contributed the most. (2) In terms of decoupling relationship between carbon emissions and income growth, rural residential buildings (RR) outperform urban residential buildings (UR) and public buildings (PB). (3) According to the dynamic simulation, the operational carbon emission in the YRD region is expected to peak at 498.18–504.83 Mt MtCO2 between 2030 and 2035. (4) The peak of PBs and URs in Nanjing, Suzhou and some third- and fourth-tier cities, and RRs in eastern and central cities in the YRD will occur at the latest, necessitating close monitoring. These findings can serve as a basis for developing scientific and reasonable building emission reduction policies in a multilevel governance context.

Estimating the Carbon Footprint of Healthcare in the Canton of Geneva and Reduction Scenarios for 2030 and 2040.

Switzerland, a wealthy country, has a cutting-edge healthcare system, yet per capita, it emits over one ton of CO2, ranking among the world's most polluting healthcare systems. To estimate the carbon footprint of the healthcare system of Geneva's canton, we collected raw data on the activities of its stakeholders. Our analysis shows that when excluding medicines and medical devices, hospitals are the main greenhouse gas emitter by far, accounting for 48% of the healthcare system's emission, followed by nursing homes (20%), private practice (18%), medical analysis laboratories (7%), dispensing pharmacies (4%), the homecare institution (3%), and the ambulance services (<1%). The most prominent emission items globally are medicines and medical devices by far, accounting for 59%, followed by building operation (19%), transport (11%), and catering (4%), among others. To actively reduce Geneva's healthcare carbon emissions, we propose direct and indirect measures, either with an immediate impact or implementing systemic changes concerning medicine prescription, building heating and cooling, low-carbon means of transport, less meaty diets, and health prevention. This study, the first of its kind in Switzerland, deciphers where most of the greenhouse gas emissions arise and proposes action levers to pave the way for ambitious emission reduction policies. We also invite health authorities to engage pharmaceutical and medical suppliers in addressing their own responsibilities, notably through the adaptation of procurement processes and requirements.

Construction and Application of Regional Carbon Performance Evaluation Index System: The Case of Chinese Provinces

As global warming becomes increasingly severe, reducing carbon emissions and promoting low-carbon development has become an international consensus. Against this backdrop, evaluating regional carbon performance helps better understand the carbon emission status, emission reduction capabilities, and low-carbon development levels, providing a scientific basis for formulating targeted carbon emission reduction policies. This study constructed a “5E” regional carbon performance evaluation index system from five dimensions: economy, effectiveness, efficiency, environmentality, and equity. Then, this study evaluated and analyzed the carbon performance of 30 provinces in China from 2008 to 2021 using the entropy weight TOPSIS method. The research results indicated that (1) during the sample period, China’s carbon performance ranged from 0.416 to 0.504, exhibiting a steady upward trend; the highest score among the first-level indicators was Effectiveness, while the lowest was Economy; (2) in terms of carbon performance among China’s three major regions, it showed a decreasing pattern from east to west, with the growth potential of the central and western regions being greater than that of the eastern region; (3) in 2033, the carbon performance of China in the eastern region, the central region, and the western region will reach 0.602, 0.612, 0.613, and 0.582, respectively. A carbon performance evaluation carries significant practical and strategic implications. Our study can provide a reference for policymakers to assess carbon emission performance and improve carbon management efficiency and decision-making levels.

A systematic approach for analyzing building energy conservation and emission reduction policies based on the principle of WSR

The building industry is a key sector that needs priority attention to achieve ‘carbon peak 2030 and carbon neutrality 2060′. Building energy conservation and emission reduction (BECER) primarily relies on policy implementation. However, current policy studies are limited to specific perspectives of policy instruments, lacking a comprehensive approach. This study proposes an analytical framework based on the theory of ‘Wuli-Shili-Renli’ (WSR) to answer the question ‘how to analyze BECER policies systematically’. Latent dirichlet allocation (LDA) topic analysis method was utilized to identify topics in the wuli dimension, while content analysis was employed to analyze policy instruments in the ‘shili’ dimension, and participants were investigated through Social Network Analysis in the renli dimension. Finally, Henan province was selected as a case study to apply the proposed WSR framework. The findings reveal that: 1) From a wuli perspective, BECER policy topics rely solely on government involvement and lack of topics that require societal or familial participation. 2) From a ‘shili’ perspective, administrative policies are dominated while voluntary and fixed policies are insufficiently represented. 3) From a ‘renli’ perspective, implementers of BECER policies are predominantly single entities with limited cooperation among different sectors. The proposed WSR framework offers an innovative approach to comprehensively researching BECER policies and can be a useful tool for formulating scientific BECER policies in specific regions.

Decoupling dynamics: Evaluating the relationship between ship emissions and socioeconomic progress in the Yangtze River Basin from 2007 to 2022

To investigate the decoupling relationship between inland ship emissions and regional socioeconomic development in the Yangtze River Basin, this study constructed an emissions inventory for inland ships from 2007 to 2022, based on inland shipping freight statistics and ship carbon pollution emission intensity. Additionally, the Petri-Tapio decoupling model was employed to analyze the relationship between ship carbon pollution emissions and per capita GDP. The study concluded that CO2 emissions from inland ships in the Yangtze River Basin increased from 2.418 million tons in 2007 to 10.801 million tons in 2022. In 2021, the emissions of NOx and SOx from inland ships in the Yangtze River Basin accounted for 2.27% and 0.0021%, respectively, of China's anthropogenic emissions. Despite a year-on-year increasing trend in ship emissions within the basin, significant reductions in PM and SO2 emissions were observed post-2018 due to the implementation of emission reduction policies. Furthermore, we found that economically developed areas such as Shanghai, Jiangsu, and Zhejiang had higher emissions compared to other regions, with regional ship emissions positively correlating with the level of economic activity. Decoupling analysis results indicated that most provinces in the Yangtze River Basin have not effectively decoupled ship carbon pollution emissions from GDP growth. The findings of this study provide support for the Chinese government to formulate stricter ship emission control policies while promoting the growth of the Yangtze River shipping economy.

Reduced interest option pricing for green bonds

PurposeThis paper originally proposed the fuzzy option pricing method for green bonds. Based on the requirements of arbitrage equilibrium, this paper draws on Merton's corporate bond option pricing model.Design/methodology/approachDescribing the asset value behavior of green bond issuing enterprises through diffusion-jump processes to reflect the uncertainty brought by carbon emission reduction policies and technologies, using approximation methods to get the analytical pricing formula and then, using a fuzzification technique of Choquet expectation under λ-additive fuzzy measures after considering fuzzy factors, the paper provides fuzzy intervals for the parity coupon rates of green bonds with different subjective levels for investors.FindingsThe paper proposes and argues the classical and fuzzy option pricing methods in turn for both corporate ordinary bonds and green bonds, considering carbon risk or climate risk. It implements the scenario analysis varying with industry emission standards and discusses the sensitiveness of the related key parameters of the option.Practical implicationsThe fuzzy option pricing for the green bonds provides the scope of the variable equilibrium values, operational theoretical supports and some policy implications of carbon reduction and promoting green funding.Originality/valueThe logic of introducing the fuzziness of the option pricing for the green bonds lies with considering the existence of fuzzy information about the project supported by the green bond and the subjectivity of investors and it also responds to changes in technological uncertainty and policy uncertainty in the process of “carbon peaking and carbon neutrality.”

Using Game Theory to Explore the Multinational Supply Chain Production Inventory Models of Various Carbon Emission Policy Combinations

This study uses Stackelberg game theory, considering different combinations of carbon emission reduction policies and that high-carbon-emission enterprises may face various carbon emission reduction regulations, to explore the production inventory problems in a multinational supply chain system. The purpose is to determine the manufacturer’s optimal production, shipping, carbon reduction investment, and the retailer’s replenishment under the equilibrium for different carbon emission policy combinations. To develop the production inventory models, this study first develops the total profit and carbon emission functions of the supply chain members, respectively, and then obtains the optimal solutions and total profits of the manufacturer and the retailer under different carbon emission policy combinations through the mathematical analysis method. Further, this study used several numerical examples to solve and compare the proposed models. The results of numerical analysis show that regardless of the increase in carbon price or carbon tax, the manufacturer and retailer will adjust their decisions to reduce carbon emissions. Specifically, an increase in the carbon price contributes to an increase in the total profit of manufacturers, while an increase in the carbon tax reduces the total profit of manufacturers. This study also explores a sensitivity analysis on the main parameters and has yielded meaningful management insights. For instance, in cases where low-carbonization strategies are required, the manufacturer or retailer can effectively reduce the carbon emissions resulting from production or purchasing activities, thereby significantly reducing overall carbon emissions. It is believed that the results of this study can provide enterprises/supply chains with reference to their respective production, transportation, carbon reduction investment, and inventory decisions under carbon emission policies, as well as information on partner selection and how to adjust decisions under environmental changes.

Sustainable-Driven Renovation of Existing Residential Buildings in China: A Systematic Exploration Based on Review and Solution Approaches

Under the backdrop of China’s national strategy to achieve carbon neutrality by 2060, efforts are underway across governmental, corporate, societal, and individual sectors to actively explore energy-saving renovations in existing buildings. Given that residential buildings constitute a significant proportion of the total energy consumption throughout the lifecycle of buildings in China, sustainable renovation of residential structures can contribute significantly to implementing China’s carbon emission reduction policies. While there exists a plethora of technological means in the market aimed at improving the energy performance of residential buildings, there still needs to be a more systematic discussion on the framework for sustainable renovation of existing Chinese residential buildings, with knowledge dissemination still needing to be more cohesive. In this context, this paper provides a comprehensive review of the field, utilizing bibliometric methods. Through a systematic review of selected peer-reviewed literature from the Web of Science and Scopus databases, the study focuses on the sustainable renovation of existing Chinese residential buildings, categorizing the process into three main stages: sustainable renovation, building performance simulation and suitability assessment. The paper also reviews the research methods adopted by previous researchers in the renovation, simulation and assessment stages, considering various optimization algorithms, variables, objectives, and software tools. Subsequently, the paper synthesizes a research framework comprising these three stages combined for different research objectives, aiming to assist policymakers, designers, and researchers in gaining a comprehensive understanding of the implementation status of sustainable renovation in existing Chinese residential buildings, identifying barriers to implementation, and formulating more efficient renovation policies and strategies for the future.

Renewable Energy Support Through Feed-in Tariffs: A Retrospective Stakeholder Analysis

Abstract This study develops a generalized evaluation framework that can be used to quantify the financial, economic, stakeholder, and environmental impacts of renewable energy support programs. The application of this framework is demonstrated by evaluating the feed-in tariff (FIT) program for solar distributed energy resources (DER) in Ontario, Canada. Our analysis reveals that Ontario’s FIT program has successfully promoted the adoption of solar DER across communities. However, the program has caused inequitable societal outcomes through a cross-subsidization with a present value of 9 CAD billion, paid for by the electricity consumer base for the benefit of only the 0.06 percent of electricity consumers who could install solar systems. The cost imposed on the Canadian economy ranges from 2.86 to 5.37 CAD billion, depending on the discount rate applied. The sensitivity analysis results indicate that the burden of this program on the Canadian economy would have been reduced by 50 percent if the program had been delayed and implemented in 2016 instead of 2010 due to the declining trend in solar system investment costs. The lessons from this analysis provide insights for designing future environmental and emission reduction policies.

Spatiotemporal Dynamics of CO2 Emissions in China Based on Multivariate Spatial Statistics

With China’s rapid industrialization and urbanization in the process of socio-economic development, the extensive use of energy has resulted in a large amount of CO2 emissions, which puts great pressure on China’s carbon emission reduction task. Through multivariate socio-economic data, this paper proposes an extraction and screening method of multivariate variables based on land-use types, and the downscaled spatial decomposition of carbon emissions at different scales was carried out by using the spatial lag model (SLM). This paper makes up for the shortcomings of previous studies, such as an insufficient modeling scale, simple modeling variables, limited spatio-temporal span of spatial decomposition, and no consideration of geographical correlation. Based on the results of the spatial decomposition of carbon emissions, this paper explores the spatial and temporal dynamics of carbon emissions at different scales. The results showed that SLM is capable of downscaling the spatialization of carbon emissions with high precision, and the continuity of the decomposition results at the provincial scale is stronger, while the differences of the decomposition results at the municipal scale are more obvious within the municipal units. In terms of the spatial and temporal dynamics of CO2 emissions, carbon emissions at both scales showed a significant positive correlation. The dominant spatial correlation types are “Low–Low” at the provincial level, and “Low–Low” and “High–High” at the municipal level. The smaller spatial scope is more helpful to show the geographic dependence and geographic differences of China’s carbon emissions. The findings of this paper will help deepen the understanding of the spatial and temporal changes of carbon emissions in China. They will provide a scientific basis for the formulation of feasible carbon emission reduction policies.

Cost Benefit Analysis of Vehicle Emissions Reduction Policies in Canada: A Case Study of Zero-Emission Vehicles

Canada has been at the forefront of mitigating climate change by adopting strategies that align with the international objective of limiting global warming. For instance, the Canadian government has intervened in the transport sector by enacting vehicle emission reduction policies such as the ZEVs policy that encourages the adoption of EVs, FCVs, and PHEVs. The policy aligns with the Canadian governments ambitious target of getting more ZEVs on Canadian roads as a strategy to achieve 100 percent zero-emission vehicles by 2040, with interim goals of 10 percent by 2025 and 30 percent by 2030. However, although ZEVs offer Canada an opportunity to reduce its GHG emissions in the transport sector, there has been concern about the upfront costs associated with adopting ZEVs, which continue to be a major deterrent despite their operation and maintenance costs being low. The following research paper conducts a CBA on ZEVs compared to CVs in Canada in terms of ownership costs and environmental impact.

CO2 Capture Cost Reduction Potential of the Coal-Fired Power Plants under High Penetration of Renewable Power in China

With a significant share of renewable power generation integrated into the power supply, it is crucial to timely adjust the regulating peak load for coal-fired power plants equipped with CO2 capture to ensure the stable operation of the multi-energy supply system. In this paper, the effects of varying boiler loads on the techno-economic performance of the retrofitted power plant were studied. Furthermore, the potential for reducing the cost of CO2 capture was investigated, and early opportunities for demonstration were discussed. Results showed that when the boiler load decreased from 100% turbine heat acceptance condition to 50% turbine heat acceptance condition, the cost of CO2 capture increased from 37.0 $/t CO2 to 57.0 $/t CO2, cost contribution of energy penalty and extra capital investment also increased from 20.6 $/t-CO2 to 25.7 $/t-CO2, and from 16.4 $/t-CO2 to 31.3 $/t-CO2, respectively. Furthermore, by improving separation efficiency from 0.15 to 0.5, a 25% to 30% reduction in CO2 capture cost can be achieved. The cost of CO2 capture could decrease by 42.2–50.5% when the cumulative capacity reaches 250 GW under the high investment learning rate scenario. According to the distribution of coal prices and renewable energy sources in China, the early demonstration projects of multi-energy supply systems should prioritize the northern region. The results of this work can provide informative references for making roadmaps and policies for CO2 emission reduction toward carbon neutrality.

Analysis of the spatial mismatch pattern of net carbon in agriculture and its influencing factors

Agricultural production has dual functions as a carbon emitter and sink, and fully exploiting the carbon sink function of agriculture is highly valuable for ensuring carbon neutrality. The layout of net carbon in agriculture shows an imbalance, i.e., underscaling in areas with a net carbon advantage or overscaling in areas with a net carbon disadvantage, which restricts the fulfillment of agricultural carbon sinks. Clarifying the global pattern of net carbon imbalances in agriculture and their drivers is highly important for improving the overall net carbon. In this regard, this paper focuses on the global net carbon in agriculture in 155 countries and regions, and a spatial mismatch index of net carbon in agriculture (MNCA) is constructed based on the relative difference between net carbon and cultivated land. Spatial autocorrelation analysis and the standard deviation ellipse are used to reflect its spatiotemporal evolution pattern. In addition, through geographically weighted regression, we explored the effects of agricultural structure, agricultural economic development, the scale of labor and cultivated land and organized the mismatches into carbon and area effects. The results show that (1) global agricultural production represents net carbon emissions, while developing countries represent net carbon sinks, and there is a mismatch of net agricultural carbon in most regions; (2) the MNCA is characterized by low-low clustering in North America, Asia and Europe, with its center of gravity falling in western Africa and migrating northeastward; and (3) the main factors influencing the MNCA are the agricultural structure and economic level. Underscaling in areas with a net carbon advantage is a major problem. To increase the global agricultural carbon sink capacity, we suggest that North America, South Asia and other regions strictly implement agricultural emission reduction policies and that Central America, South America and Africa tentatively upgrade agricultural technology and their economies to alleviate farmland pressure through transnational cooperation. In this paper, the global net carbon imbalance in agriculture is identified and the overall implementation path of increasing carbon sinks is explored to provide a reference for achieving carbon neutrality. SynopsisThis study reports a global mismatch in net carbon in agriculture and identifies the wasted carbon sink advantage of developing countries as the root problem.

Managing Uncertainty in Urban Road Traffic Emissions Associated with Vehicle Fleet Composition: From the Perspective of Spatiotemporal Sampling Coverage

With pronounced differences in emission factors among vehicle types and marked spatiotemporal heterogeneity of vehicle fleet composition, extrapolating fleet composition from insufficient sample hour periods and road segments will introduce significant uncertainty in calculating regional daily road traffic emissions. We proposed a framework to manage uncertainty in urban road traffic emissions associated with vehicle fleet composition from the perspective of spatiotemporal sampling coverage. Initially, the respective relationships of the temporal and spatial sampling coverages of fleet composition with the resulting regional daily road traffic emission uncertainties were determined, using the core area of a typical small and medium-sized city in China with the widely-used International Vehicle Emissions (IVE) model as example. Subsequently, function models were developed to explore the determination of the spatiotemporal sampling coverage of fleet composition. These results of emission uncertainties and function models implied that gases with larger emission factor discrepancies between vehicle types, such as NOx, required greater spatiotemporal sampling coverage than gases with smaller discrepancies, such as CO2, under the same uncertainties target. Therefore, sampling efforts should be prioritized for gases with larger emission factor discrepancies. Additionally, increasing sampling coverage in one dimension (either spatial or temporal) can reduce the minimum required coverage in the other dimension. To further reduce uncertainty, enhancing both spatial and temporal sampling coverage of the fleet composition is more effective than enhancing one type of coverage alone. The framework and results proposed in this work can reduce the uncertainty of emissions calculations caused by insufficient sampling coverage and contribute to more accurate transport emission reduction policy formulation.

Cooperation models in automotive supply chain under low-carbon emission reduction policies

Cooperation models in automotive supply chain under low-carbon emission reduction policies

Is South Korea's 2050 Carbon-Neutral scenario sufficient for meeting greenhouse gas emissions reduction goal?

In line with Global Climate Change Alliance initiated in 2007 by the European Commission, the South Korean government announced the “2050 Carbon-Neutral Strategy” in October 2020. The 2050 Carbon-Neutral Scenario was announced in October 2021, with the aim of reducing the country's greenhouse gas (GHG) emissions by 40 % by 2030 compared to those in 2018. The primary objective of this study is to conduct a scenario-based comparative analysis focusing on the forecast of greenhouse gas emissions and the potential for reduction within the building sector. The methodology employed in this study utilizes the greenhouse gas emission calculation methods outlined in the IPCC Guidelines of 1996 and 2006. Based on the national building energy and statistics database for the years 2015 to 2019, the study analyzes building types, building energy intensity, and floor areas to calculate emissions and energy consumption within the sector. The results indicate that the emissions will increase continuously from 2020 (156.9 million tons of CO2 equivalent) to 2050 (217.8 million tons of CO2 equivalent). We have considered the four scenarios outlined in the ‘2050 Carbon Neutrality Scenario’ as the most effective strategies for reducing greenhouse gas emissions in the building sector. These include: (1) Mandatory implementation of Zero-Energy Buildings (ZEB) for new buildings by 2050, (2) 100 % execution of green remodeling for existing buildings, (3) Promotion of high-efficiency devices to achieve a 25–30 % improvement in energy consumption efficiency compared to 2018 and an enhancement of device energy use per unit, and (4) Expansion of clean heat utilization such as fuel cells and waste heat utilization in district heating. Thus, the possibility of South Korea achieving the 2050 carbon-neutrality target in the building sector is low. Therefore, it is important to develop effective emissions reduction policies and plans for the building sector.

Can China Reach Its Carbon Peak Before 2030? An Empirical Study Based on China's Carbon Emission Data

The global surge in the warming trend is predominantly attributed to the substantial release of greenhouse gases, notably carbon dioxide. Despite continuous international efforts to curb these emissions, our country, marked by the largest population and energy consumption, stands as a major contributor to carbon dioxide emissions. Unlike developed nations, we face a more formidable challenge in reducing emissions, demanding intensified endeavors. To address climate change, our nation has set a crucial carbon emission target: achieving a carbon peak before 2030 and attaining carbon neutrality by 2060. The "14th Five-Year Plan" of each province underscores the significance of "carbon peaking and carbon neutrality," tailoring emission reduction policies to individual economic landscapes. Current research inadequacies hinder theoretical guidance needed to meet the 2030 carbon peak. Crafting province-specific emission reduction strategies is thus imperative. This study aims to scrutinize national and regional carbon dioxide emissions in four distinct Chinese regions, utilizing the STIRPAT model to predict emissions from 2020 to 2030 under the "low development and strong low carbon" paradigm. Initial analysis from 2004 to 2019 showed an annual increase in national and provincial carbon dioxide emissions, revealing significant regional differences. Six prominent factors influencing emissions were identified. The STIRPAT model predicted emissions for 2020 to 2030, indicating that achieving carbon peaking before 2030 is unfeasible under the baseline scenario. However, within the "low development and strong low carbon" framework, attaining this goal becomes plausible.

Research on the coordinated development of provincial urbanization and carbon emission efficiency of construction industry in China

BackgroundEnergy conservation and emission reduction policies restrict the economic and social development of all countries in the world, and the impact on China, which has low urbanization, is more serious. In the process of promoting urbanization, the pressure of carbon emission reduction in the construction industry has increased, and the high emissions of the construction industry have made the low-carbon development of cities face severe challenges. China is at a critical stage of urbanization development, and there is become a general consensus on how to improve the carbon emission efficiency of the construction industry. The interaction between urbanization and the carbon emission efficiency of the construction industry is a long-term and complex process. As one of the industries contributing to China’s urbanization process and carbon emissions, it is of great practical significance to explore the coordination relationship between urbanization and the carbon emission efficiency of the construction industry (CEECI) to realize the goal of “double carbon”, promoting urbanization construction and solving the problem of “green development”. Taking 30 provinces in China as the research target area, the double weighted summation method and the undesirable output superefficiency window-EBM-DEA model are used to measure the provincial urbanization level and CEECI, respectively. Then, the coupling coordination degree model of the relative development index is introduced, and the spatial autocorrelation model and the spatial and temporal differentiation characteristics of the coordination level of urbanization and the CEECI are analysed.ResultsFrom 2010 to 2021, China’s urbanization level increased steadily, but the growth rate gradually decreased. There were significant differences in urbanization levels among provinces. The eastern provinces have a higher level of urbanization but lack an impetus in the later period, while the western provinces have a lower level of urbanization but a faster growth rate. The low-carbon development trend of China’s construction industry is good, and the overall development of the CEECI shows an “N” type, and the inflection points appear in 2013 and 2018. The interprovincial urbanization level is significantly different from that of the CEECI, and the development form of the central and western provinces is better than that of the eastern provinces. The coordination level of urbanization and the CEECI in China is transitioning from the running-in stage to the coordination stage, and the coupling coordination degree between systems is on the rise, while the relative development degree is on the decline. The spatial distribution pattern is in a dynamic state of change, and the overall distribution pattern is “high in the east and low in the central and western regions”. The differences among provinces were significantly decreased, with 63.33% of provinces at the high running-in level. The provinces that entered the coordination stage were mainly located in the eastern region, and only Beijing was in the coordination stage by the end of the study. In addition, 90% of the provinces exhibited lagging efficiency, and only Jiangxi, Guangxi and Chongqing, which had low coordination levels maintained synchronous development of the two systems. The coordination level between provincial urbanization and the CEECI showed a positive spatial distribution, the global Moran index showed a “V” shape trend, and the spatial dependence of the coordination level between the two systems gradually weakened. In the local spatial distribution, there are two types of convergence: high and low.ConclusionsThe coordination degree of urbanization and the CEECI analysed in this study is an extension of the research on the relationship between the two. By integrating the two into a unified framework, the method of combining quantitative and qualitative analysis is used to further explore the coordination relationship between the two, which not only enhances the scientificity and accuracy of the research but also extends the breadth and depth of relevant theoretical research. At the same time, according to the coordination type between urbanization and the CEECI, China should propose corresponding targeted coordination and optimization paths from the perspective of urbanization and low-carbon development of the construction industry to achieve high-quality development of China’s economy and society.