Environmental Input-output Analysis Research Articles

Identification on the common supply chain paths of CO2 and NOx emissions from the manufacturing industry in China

ABSTRACT Since the ‘Made in China 2025’ initiative was proposed, the transformation and upgrading of China’s manufacturing industry towards a high-end, intelligent, and green status has been accelerated, and the climate change and air pollution issues draw immediate attention. This paper investigated the simultaneous control paths of CO2 and NOx emissions throughout the manufacturing transition in China. Based on environmental input-output analysis, the production- and consumption-based CO2 and NOx emissions in 2015 and 2020 were evaluated, indicating that over 70% of production-side emissions were caused by medium-technology manufacturing, and over 50% of consumption-side emissions came from high-technology manufacturing. Then, the structural path analysis was introduced to extract the synergistic emission pathways of CO2 and NOx. The ‘smelting and pressing of metal sector → construction → investment’ pathway, which produced emissions of 347.71 Mt CO2 and 639.9 Kt NOx in 2015, was identified as the most critical path to achieve manufacturing synergistic reduction. Additionally, investment demand in the construction sector seriously affected the collaborative reduction of CO2 and NOx emissions in supply chains of medium-technology manufacturing. The critical supply chain of high-technology manufacturing for achieving coordinated emission reduction was mainly driven by export demand for chemical products.

A comprehensive analysis of the energy, economic, and environmental impacts of industrial variable frequency drives

Motor systems are ubiquitous throughout the industrial sector, particularly in fluids applications. It is well known that the efficiency of these operations can be greatly enhanced using variable frequency drive (VFD) controls, but adoption of the technology is far from universal. The goal of this paper is to introduce engineering, economic, and environmental analyses to demonstrate benefits to both individual facilities and the state at large. Individual case studies are presented to describe the variety of opportunities for VFD-enhanced motor control; however, this project seeks to describe the combined impact of VFD implementation at a new scale. Data sourced from a U.S. Department of Energy program is used to perform economic and environmental input output analysis to calculate broad impacts of individual audits and recommendations. Results indicate that widespread implementation of VFD controls on motor systems in the industrial sector will introduce significant economic and environmental benefits. One of the scenarios showed a potential reduction of over 4.7 million tonnes of carbon dioxide from regional manufacturing sector as well as a cascading contribution to the regional economy totaling nearly $1 billion. The results are presented as a demonstration of the magnitude of impact that improving control of industrial motor systems can have, as a guide to industry leaders and policymakers about the value of such investments.

Unpacking the urban virtual water of the Global South: Lessons from 181 cities

Most of the water humanity currently consumes is invisible, it is embedded within goods and services purchased by final consumers from the global economic market. Cities of the Global South (GS) – especially African and Asian cities are facing twofold water security problems. First, the increased risk of water availability (both quantity and quality), which is exacerbated by climate change. Second, the ever-increasing water demand due to their economic and population growth. Therefore, to help cities of the GS to efficiently manage their water resources, it is crucial to explore what products are being imported from the global economic market and assess their embodied water intensities. Herein, the water footprints (blue and grey) of 181 cities from the GS are computed using Extended Environmental Input-Output Analysis (EE-IOA). Results point out that water imports through virtual water are significant and growing even across the GS with different magnitudes because of the economic attributes of cities (expenditures patterns) and their geography (spatial location). The average blue virtual water is estimated to be 253 l per capita/yr and 285 l per capita/yr for virtual grey water. When decomposing the water footprint we found that the major responsible sectors are “Food” accounting for 37% of the total footprint, followed by “Transport” with 24%, and “Energy” with 22%. To put the climate impacts in perspective, cities of the GS must act in a proactive approach and use the water-trade nexus as a supplementary approach to shape and implement water security strategies.

Decarbonization in New Zealand – where and how: a combination of input–output approach and structural decomposition analysis

In New Zealand, agriculture accounts for around 50% of total gross greenhouse gas emissions, energy production and use account for 40%. Given the limited possibility of reducing methane from the agricultural sector, we focus on the shape of, and factors influencing, the energy-related emissions profile. A single framework that combines environmental input–output analysis with structural decomposition analysis is established to systematically investigate driving forces shaping energy-related greenhouse gas emissions at national and sectoral levels. Results show that emission intensity, population, and consumption volume are dominant factors influencing shifting the energy-related emissions profile from 2007 to 2013. To achieve a net-zero-carbon economy, decarbonizing the transport sector is foremost and should be given priority. Policy directed at improving energy utilization in private consumption and exports, and the adoption and utilization of advanced technology in manufacturing, would contribute to achieving emissions reduction targets.

Estimating the greenhouse gas emissions of cold chain infrastructure in China from 2021 to 2060

Cold chain infrastructure is vital in the modern food system, yet the greenhouse gas (GHG) emissions of cold warehouse construction and operation are unclear. This article fills the gap by presenting an environmental modeling study to estimate the future trajectory of GHG emissions of cold warehouses in China from 2021 to 2060. A hybrid analysis is used to estimate the potential GHG emissions over time, using environmental input-output analysis (EIO) for construction and process-based analysis for operation. We analyzed five scenarios: cleaner refrigerants (CR), cleaner electricity sources (CE), higher energy efficiency (HE), cleaner cold warehouses (CCW), and a business as usual (BAU) scenario. The results show the trend of GHG emissions in all scenarios and reveal the effectiveness of these measures, with cleaner electricity sources and higher energy efficiency having stronger impacts than introducing cleaner refrigerants on reducing GHG emissions. Another key finding is that electricity consumption during cold warehouse operation is responsible for over 85% of total emissions in 40 years in all scenarios.

Decomposition of China's regional carbon emission paths: an analysis of environmental input and output considering regional development differences.

At present, the imbalance in regional development and carbon emissions are the two major challenges that China faces in terms of achieving high-quality development. This paper takes regional development differences as the starting point. First, we adopt the improved CRITIC method to measure the comprehensive development level of 30 regions in China and use K-means clustering to divide the 30 regions into five development levels. Second, the structural path analysis for environmental input-output analysis (EIOA-SPA) model is used to quantify the transfer of carbon emissions between sectors in various regions. Finally, a comprehensive analysis is performed based on the development characteristics of each region and the decomposition results of the carbon emission paths. Then, more precise carbon emission reduction strategies are proposed for the development of different regions in China. The results show that first, the development gap between regions in China has improved, and the development of the central and western regions has achieved remarkable results. However, differences between the north and the south and the gap between coastal and inland regions still exist. Second, the direct carbon emissions of regions with different levels of development are mainly derived from high energy-consuming sectors, especially the production and supply of electricity and heat sector. Third, there are certain differences in the indirect carbon emission pathways of regions with different development levels. The transportation, storage, and postal sector in high developed regions have obvious driving effects on carbon emissions. The building sector plays a prominent role in driving carbon emissions in high developed regions and medium-high developed regions. The building sector, nonmetallic mineral products sector, metal smelting sector, and rolled processed product sector in medium developed regions and medium-low developed regions have relatively high carbon emission-stimulating effects. Therefore, it is necessary to adopt differentiated emission reduction strategies for regions with different development levels in China to achieve adequate carbon emission reductions. This effort would further promote the construction of China's ecological civilization.

Development of an SMR-induced environmental input-output analysis model – Application to Saskatchewan, Canada

As an emerging power generation technology, small module reactors (SMRs) have the potential for development with its contribution to reducing greenhouse gas (GHG) emissions. In this study, an SMR-induced environmental input-output model (SEIOM) is proposed to simulate the environmental consequences of SMRs development and provide suggested schemes for SMRs deployment. A case study of Saskatchewan, Canada is conducted to demonstrate the proposed model. Specifically, key industries with high reduction potentials are first identified in the study; then, the power supply for three energy-intensive industries is assumed to be replaced by power generated from SMRs at various penetration degrees. The corresponding changes in direct and indirect GHG emissions and the interrelationships among multiple economic sectors associated with GHG flows are analyzed. The results indicate that there are close interdependences between various sectors and a small group of sectors could play a big role in GHG emission mitigation. In Saskatchewan, “Electricity power generation, transmission and distribution”, “Oil and gas extraction”, “Potash mining” and “Petroleum refineries” are key sectors for realizing GHG emission reduction targets. Meanwhile, it is estimated that replacing the power supply for “Oil and gas extraction” sector with SMRs would contribute the most to the reduction in GHG emission, which is much more than those for “Potash mining” and “Petroleum refineries” sectors. This study is expected to provide a basis for supporting the initiative and application of SMRs.

Impact of Renewable Energy on Carbon Dioxide Emission Reduction in Bangladesh

Economic growth and industrialization often default to a great dependency on fossil fuels (FF) to supply power needs. The carbon rich nature of FF combustion can impact global warming. Therefore, it is conducive to transition from FF to renewable energy (RE). The present study aimed to address if replacement of a single FF by RE can mitigate carbon emissions. We conduct the study in a country undergoing mass urbanization and challenging energy demands. Data from energy resources in the Power & Energy Sector Master Plan (PSMP2016; Bangladesh) are analyzed over the 2017-2021 trajectory. Two scenarios for imports, oil and coal are assessed. Environmental input output (E-IO) analysis and percentage equivalence analysis measured data variables. The data is then further disaggregated into an emission reduction (ER) model with sensitivity analysis to measure carbon emission reduction when each FF source is substituted by RE. Results show the percentage share of energy generation capacity by both coal and RE increase over time. Solar and wind power contribute to the increase in RE. When oil is imported a 1% increase in oil, coal, and gas-based energy generation capacity increases carbon emissions by 1.25%, 1.48% and 0.93%, respectively. 1% increase in RE produces negligible carbon emissions (0.0042%). There was little difference in the percentages of carbon emissions when coal is imported. Substituting any FF with RE of equal energy capacity does not, in the short term, reduce carbon emissions in either scenario. Therefore, we conclude that for long term clean energy prospects in Bangladesh, RE needs to be developed to operate at greater capacity in conjunction with other carbon management factors. The research findings herein offer insights for clean energy implementation in developing nations.

The Effort To Reduce Negative Externality In Post Covid-19 Period In Turkish Economy: Example Of Transportation Sector

Every production element creates negative externality. In this study, the negative externality created by the transportation sector is investigated by extended environmental input-output analysis. In the WIOD input-output table, the transportation sector consists of three sectors as land transportation, air transportation and water transportation. As a result of the analysis carried out in this context, normalized total backward CO2 linkages coefficients are 0,4500 kt CO2 equivalent in land transportation, 0,8929 kt CO2 equivalent in air transportation, and 0,3619 kt CO2 equivalent in water transportation respectively. Normalized total forward CO2 linkages coefficients were found as 1.1895 kt CO2 equivalent in land transportation, 0.77840 kt CO2 equivalent in air transportation and 0.3234 kt CO2 equivalent in water transportation. The Spearman correlation coefficient was calculated to determine whether the transportation sectors' inter-period production chain changed structurally. It was concluded that the input components used in production did not differ significantly. It is predicted that the obtained results will increase even more in the post-covid-19 period and it is recommended to take measures and determine policies for a transportation system in which emission production is limited and renewable and sustainable environmentally friendly fuel types are preferred.

Identifying the key sectors for regional energy, water and carbon footprints from production-, consumption- and network-based perspectives

Energy consumption, water use and carbon emission targets are important for promoting sustainable development. This study presents a multi-goal analytical framework based on an environmental input-output analysis, structural path analysis and correspondence analysis to identify the key sectors for energy, water and carbon footprints. Using Guangdong Province as a case study, the energy, water and carbon footprints are modelled from production-based, consumption-based and network (betweenness)-based perspectives. The results show that (1) the construction sector is a key sector for energy use/water use/carbon emissions from the three perspectives. The electricity and heat power production and supply sector emitted the most production-based CO2 (283.4 Mt), accounting for 52.3% of the total CO2 emissions. (2) The key sectors in terms of energy, water and carbon differ. The transport, storage and post sector is an important sector for energy consumption, and the agriculture sector and food and tobacco sector are important sectors for freshwater withdrawal. (3) The key sectors differ according to the three perspectives. For example, the energy production sector ranked first in production-based CO2 emissions (286.2 Mt), but heavy manufacturing ranked first in consumption-based CO2 emissions (146.3 Mt). This study recommends paying more attention to the abovementioned sectors, specifically concerning the transmission role of light manufacturing in freshwater withdrawal, and reducing energy consumption-intensive but low value-added exports (such as metal smelting and pressing). The findings highlight the need to consider multiple angles and elements to identify the key sectors and help decision makers better understand the relationships and flows among the industries.

Validity and Reliability of Life Cycle Assessment: A Case Study of New Zealand Dairy Production

The purpose of this work is to evaluate the validity and reliability of life cycle assessment as a research methodology to measure the ecological footprint of New Zealand’s dairy production (by the dairy farming and dairy processing sectors). Environmental Input-Output Analysis was used as a macro-level life cycle assessment tool and applied to the dairy production over a period of six years. Eco-efficiencies were used as performance metrics to assess the sustainability of the dairy production. Over the six year period, New Zealand’s annual milk production increased from 11.4 to 15.1 million tonnes and its annual production of dairy products increased from 1.9 to 2.6 million tonnes. Eco-efficiencies indicate that over this time dairy farming became significantly more efficient in terms of land use (-27%), electricity use (-12%), water use (-21%) and lime use (-16%) and produced significantly less water-based effluent (-20%). At the same time fuel and fertilizer use were slightly less efficient (increasing by 2% and 6% respectively). The dairy processing industry used 21% less water and discharged 21% less effluent water. Fuel used in milk transportation was 14% more efficient. The internal validity of the research was good despite significant structural changes to the dairy processing sector but commercial sensitivity had a negative impact on the results. External validity was affected by different boundaries, different climates and different time frames for published studies but some comparisons were possible. The underlying data was generally accurate, reproducible and representative of the entire sectors with checks for anomalies to ensure good reliability. The choice of Environmental Input-Output Analysis for the life cycle assessment tool and error analysis of all underlying data contributed to both the validity of the research method and the reliability of the data. These, in turn, give good credibility to the research findings.

Identifying key sectors based on cascading effect along paths in the embodied CO2 emission flow network in Beijing-Tianjin-Hebei region, China.

The emission of carbon dioxide (CO2) is a serious environmental issue, especially in Beijing-Tianjin-Hebei region. Unlike previous studies that mainly consider the bilateral and direct connection between two sectors, this study identifies path-based key sectors by considering the cascading effect of a sector on other sectors on paths of the entire economic system. We first construct an embodied CO2 emission flow network of Beijing-Tianjin-Hebei region, combining environmental input-output analysis and complex network theory. Then, the path-based key sectors are identified by traversing the path of each sector in the network based on cascading failure theory and hypothesis extraction method. On the one hand, the results show that a small number of sectors shoulder a large proportion of the embodied CO2 emission flows from both path and sector perspectives. On the other hand, we identify some path-based key sectors that did not receive enough attention from the sector perspective. Additionally, the sum of the embodied CO2 emission flows in about 30 steps accounts for 90% of the total embodied CO2 emission flows on its supply chain path. To more effectively reduce carbon emission, sectors that connect these 30 steps should be concerned in some policy recommendations. The method proposed in this paper can complement existing methods and contribute to further reducing CO2 emissions in the Beijing-Tianjin-Hebei region.

Three-perspective energy-carbon nexus analysis for developing China's policies of CO2-emission mitigation

Energy usage and CO2 emission have intimate and inseparable linkages. The growth of energy usage causes an increase in CO2 emissions, which will in turn constrain the related energy policies and challenge the energy-system stability. It is essential to quantify China's CO2 emission inventories embodied in production-driven, demand-driven and supply-driven chains considering different energy types. A Three-Perspective Energy-Carbon Nexus model is developed to facilitate comprehensive CO2 emission-reduction analysis in China. The model incorporates environmental input-output analysis and ecological network analysis within a general framework to clarify the relationships among provinces in terms of the production-based, consumption-based and income-based accountings. A new indicator, indirect emission dominant factor, is for the first time examined to evaluate the dominant capabilities of indirect emissions. It is discovered that the emissions triggered by the demand-side are not sensitive to energy types. Furthermore, the changes of integral flow control intensity in each province are insignificant from consumption-based and income-based perspectives. Final demand contributes 80% of consumption-based emissions and gross value-added creation leads to a total of 82% income-based CO2 emissions in China in 2012. When controlling emissions from multiple perspectives, traditional methods may not be effective since they do not consider the forms of emissions; some methods (e.g., product allocation) are not suitable for suppressing indirect emissions. Moreover, the prosperity of developed regions (e.g. Guangdong) highly rely on support from underdeveloped regions (e.g. Inner Mongolia). Some underdeveloped provinces are receptors of CO2, while the developed ones are emitting CO2 to the system without assuming their emission-reduction responsibilities. In addition, secondary energy consumptions in developed regions are conducive in increasing their emission contributions to the system. In this research, an innovative perspective is initiated to disclose the energy-carbon interconnections across Chinese provinces. The obtained findings could help support the formulation of China's CO2 emission-reduction policies.

Physical Water Use and Water Sector Activity in Environmental Input-Output Analysis

This paper uses input-output accounting methods to identify the direct, indirect, and induced physical demand for water. The seminal work by Leontief (1970) has previously motivated a more extensive account of issues related to those sectors that generate and those that clean/treat polluting outputs. The present paper extends this approach to deal with sectors that use a natural resource and those that supply it. We take, as a case study, public water use and supply in Wales. The analysis shows how the proposed method, using both the quantity input-output model and the associated price dual, can be used to investigate the economy-wide implications of the deviation between expenditures on the output of the water sector and actual physical water supplied. The results indicate that the price paid for water varies greatly amongst different uses; in particular, household consumption is charged at a higher price than intermediate industrial demand. We argue that decision makers (in this case, policy makers and industry regulators) require such analysis and information in order to understand the demands on and supply of water resources and their role in supporting economic expansion, whilst simultaneously adopting appropriate strategies for achieving water sustainability objectives.

Accounting the Virtual Water and Virtual Land Based on Input-output analysis-- A Case Study of Zhangye City

Water and land are the basic elements of ecological protection, economic development and human life in Zhangye city. The virtual water and virtual land accounting are the core research content to achieve sustainable development in this area. In this paper, the virtual trade of water and land in Zhangye city is analyzed via environmental input-output analysis. It is found that the virtual water and land in this area are in a net outflow state. From the perspective of sectors, the agricultural sector is the largest net outflow sector of virtual water and virtual land, while the manufacturing sector is the net inflow sector. The accounting in this paper can provide a solid foundation for the formulation of industrial and trade policies.

An in depth economic restructuring framework by using particle swarm optimization

The aim of this paper is the development of an integrated framework, based on environmental input-output analysis, for optimizing the economic structure of an economy. The restructuring process is approached as a constraint optimization problem where the optimized variables are the elements of the matrix of domestic technical coefficients. A method for determining the optimal level of the productive linkages of an economy in order to maximize its output with the minimal greenhouse gas emissions the possible is suggested. The proposed methodology is able to join both environmental and economic policy targets, in the form of predefined constraints. The objective function, which is going to be minimized, expresses the greenhouse gas emissions (GHG) intensity or GHG emissions per unit of output. A particle swarm algorithm is employed for the solution of the optimization problem. An illustrative application to the Greek economy was carried out. The experimental results revealed that if the Greek economy will apply policies for boosting the sectors of high and medium-high R&D intensity, then the greenhouse gas emission per unit of gross domestic product of Greece would be reduced. Furthermore, the promotion of high and medium-high R&D intensity sectors is connected with an important improvement of the production linkages to a wide range of sectors, highlighting the important spillover effect of the suggested restructuring process.

Transfer of virtual water embodied in food: A new perspective

Food and water are inextricably linked. With the increase of water consumption in irrigation and food growth, water shortage has become an urgent issue. Irrational cross-regional transfer of water embodied in food exacerbates water scarcity and restrict China's sustainable development. Given that, a Virtual Water-Food Nexus Model is developed to quantify the inter-provincial transfer of water embodied in food and to identify the complicated interactions between different provinces. In detail, Environmental Input-Output Analysis is applied to quantitatively estimate the inter-provincial water transfer embodied in food trades. Based on the network constructed by interrelated nature of nexus, the mutual interactions, control situation, and the dominant and weak pathways are examined through the combination of Ecological Network Analysis and Principal Component Analysis. Two new indictors water consumption intensity and water supply capacity are first performed to measure the role of each province from the supply and consume side respectively. It is revealed that interregional food transactions failed to realize water resources dispatching management. Many water-deficient regions suffered from massive virtual water losses through food exports, but water-rich areas still import large quantities of food containing virtual water. Results show that exploitation and competition dominate the ecological relationships between provinces. Agricultural GDP ratio is the indicator which most affect water consumption intensity and water supply capacity. Network-based research contributes more insights into the recognition of water management responsibilities across provinces and municipalities. These findings will provide a scientific support to adjust unreasonable allocation of water resources in China in an attempt to addressing the contradiction between food demand and water shortages.

Implementation of stochastic multi attribute analysis (SMAA) in comparative environmental assessments

The selection of an alternative based on the results of a comparative environmental assessment such as life cycle assessment (LCA), environmental input-output analysis (EIOA) or integrated assessment modelling (IAM) is challenging because most of the times there is no single best option. Most comparative cases contain trade-offs between environmental criteria, uncertainty in the performances and multiple diverse values from decision makers. To circumvent these challenges, a method from decision analysis, namely stochastic multi attribute analysis (SMAA), has been proposed instead. SMAA performs aggregation that is partially compensatory (hence, closer to a strong sustainability perspective), incorporates performance uncertainty in the assessment, is free from external normalization references and allows for uncertainties in decision maker preferences. This paper presents a thorough introduction of SMAA for environmental decision-support, provides the mathematical fundamentals and offers an Excel platform for easy implementation and access.

Emergy network analysis of Chinese sectoral ecological sustainability

Ecological sustainability of the Chinese economy is vital for China as well as for the world. By integrating environmental input-output analysis, emergy theory, and a complex network model into one framework, this paper explores Chinese sectoral ecological sustainability with the most recent 2012 input-output table. The results show that there are significant differences in emergy intensities among sectors. The non-metal mining sector is the most emergy-intensive sector at 6.06E+17 sej/10000 Yuan, followed by the metal mining sector. Additionally, output connections have a positive impact on the emergy yield ratio, input connections exert a negative impact on the emergy yield ratio, and PageRank centrality has a positive effect on the environmental loading ratio. This paper updates the Chinese sectoral emergy assessment, identifies key sectors in the Chinese ecological network, and analyzes the impact of network indicators on sectoral emergy performance. These analyses will be useful in updating the guide for adjusting industrial structure in China.

An estimated carbon footprint of NHS primary dental care within England. How can dentistry be more environmentally sustainable?

Introduction National Health Service (NHS) England dental teams need to consider from a professional perspective how they can, along with their NHS colleagues, play their part in reducing their carbon emissions and improve the sustainability of the care they deliver. In order to help understand carbon emissions from dental services, Public Health England (PHE) commissioned a calculation and analysis of the carbon footprint of key dental procedures.Methods Secondary data analysis from Business Services Authority (BSA), Health and Social Care Information Centre (HSCIC) (now called NHS Digital, Information Services Division [ISD]), National Association of Specialist Dental Accountants (NASDA) and recent Scottish papers was undertaken using a process-based and environmental input-output analysis using industry established conversion factors.Results The carbon footprint of the NHS dental service is 675 kilotonnes carbon dioxide equivalents (CO2e). Examinations contributed the highest proportion to this footprint (27.1%) followed by scale and polish (13.4%) and amalgam/composite restorations (19.3%). From an emissions perspective, nearly 2/3 (64.5%) of emissions related to travel (staff and patient travel), 19% procurement (the products and services dental clinics buy) and 15.3% related to energy use.Discussion The results are estimates of carbon emissions based on a number of broad assumptions. More research, education and awareness is needed to help dentistry develop low carbon patient pathways.