Emergy Theory Research Articles

Emergy-Based Evaluation of Xiaolangdi Reservoir’s Impact on the Ecosystem Health and Services of the Lower Yellow River

The disturbance in river ecosystems caused by reservoirs and dams has become a critical topic, attracting increasing attention. However, the extent to which reservoir and dam construction and operation impact downstream river ecosystem health and ecosystem service functions is not fully understood. This research examines the Xiaolangdi Reservoir and the Lower Yellow River (LYR) ecosystem in China as a case study. We analyzed the complex material and energy flows in the LYR ecosystem using emergy theory and developed a set of emergy-based indicators for the quantitative assessment of river ecosystem health and services under reservoir operation interference. The results indicate that the total natural capital and environmental endowments of the LYR ecosystem have remained relatively stable after the operation of the Xiaolangdi Reservoir, with an increase in renewable emergy input. The ecosystem’s vigor decreased slightly, while the biomass emergy diversity index remained stable. However, the total emergy inputs increased significantly, with external feedback inputs becoming the most important emergy source for the LYR ecosystem. The resilience of the LYR ecosystem improved, with a significant increase in emergy density and a decrease in the emergy sustainability index. These findings suggest that although the river ecosystem continues to provide supporting services to human society, the extent of these services has diminished compared to pre-perturbation levels. In this research, a methodology for analyzing the impact of key reservoir operations on the ecosystem health and services of a large river is proposed to provide support for large river sustainable development studies.

Rethinking the China-U.S. Trade balance from 2001–2020 based on emergy perspective

In the year 2018, escalating trade imbalances between China and the United States led to a trade war over tariffs and trade policies that garnered global attention. While trade deficits are primarily reflected in currency terms, trade involves a broader exchange of different resources. Hence, this study employs Emergy Accounting approach (EMA), an environmental quality-oriented assessment method, to collect official statistical data from both countries and consider differences in statistical data weight. Utilizing the NEAD V2.0 database, this research calculates and discusses the total emergy flow, trade imbalances, and structures in China-U.S. trade from 2001 to 2020. Additionally, it computes and analyzes emergy indicators, delving into the dynamic changes in the emergy values of various categories of goods. The results indicate a gradual balance in the emergy trade deficit between China and the United States, with both countries benefiting from the trade. Specifically, China benefits from importing raw materials from the United States, while the U.S. gains from importing inexpensive embodied labor from China. Considering differences in data statistical calibers and applying the EMA contribute to a more accurate understanding of the trade situation and the correction or prevention of errors. The Emergy theory provides a new perspective for a comprehensive assessment of trade relationships. China and the United States have the potential to establish a fairer, more balanced, collaborative, and sustainable trade relationship, contributing to global sustainable development.

Study on the Structure, Efficiency, and Driving Factors of an Eco-Agricultural Park Based on Emergy: A Case Study of Jinchuan Eco-Agricultural Park

The eco-agricultural park is a new comprehensive agricultural technology system integrating agricultural production, rural economic development, ecological environment protection, and efficient resource utilization. Therefore, an in-depth analysis of the ecosystem structure of eco-agricultural parks will help achieve the goal of coordinated symbiosis between human development and environmental protection. This study takes the research area of the Eco-agricultural Park of Jinchuan Town, Huinan County, a typical town in the Changbai Mountains of Northeast China. Based on field surveys, market research, farmer consultation, and related data collection, emergy theory and methods are used to construct an emergy model for the park. The value evaluation index system integrates the unique emergy index of the agricultural ecosystem with the traditional emergy index system to conduct a targeted evaluation of the park’s functional structure and sustainable development capabilities in order to improve the efficiency of material and energy use and provide technical reference for ecological construction and comprehensive development of agricultural industry in mountainous areas in northern China. The research results show that: (1) The annual input total emergy of the eco-agricultural park is 4.04E+24 sej/a, and the emergy of labor input, electricity input, and topsoil loss is relatively high. The park is in a labor-intensive stage. The annual output total emergy is 5.09E+24 sej/a, the park is dominated by planting and forestry industries. (2) The park’s emergy utilization intensity is high—production efficiency is high, economic development is advanced, and the system’s self-control, adjustment, and feedback functions are vital—and plays a significant role in promoting the development of the regional economy. However, the park relies more on investment from external resources, and production in the park puts pressure on the environment. (3) The current sustainable development capability of the study area is weak, and the factors affecting the sustainable development capability are mainly energy loss and uneven distribution of industrial areas in the park. Effective measures to promote the transformation of the park to develop technology-intensive industries and improve the sustainable development performance of the park were proposed. These include: adjusting the proportion of industries in the park; reducing high-energy external input emergy, such as industrial auxiliary emergy; reducing the loss of non-renewable natural resources through ecological engineering measures, such as reducing the depth of slope runoff in the park; and combining modern resource-based production technology and environmentally sound management methods to reduce energy loss and rational use of natural resources.

Research on the sustainability assessment of sponge cities

Faced with abnormal global climate change, sponge cities are an effective response. The design of sponge cities can enhance the sustainability of the entire city, although specific quantitative effects are yet to be determined. According to the emergy theory, this article conducts a sustainability study on selected sponge city facilities in Zhenjiang City. The research results show a significant improvement in the sustainability of the study objects. Using the sustainable parameter of emergy as an evaluation criterion, there is a noticeable improvement from an initial value of 0.07 to 1.21 after the implementation of sponge measures. Additionally, the overall project design has significantly improved the sustainability of the design.

Evaluation of sustainability development of the eco-economic system of water and soil resources based on emergy analysis

Abstract Due to the swift progress of the economy and society and the rapid escalation of urbanization rates, the sustainable examination of individual water or land resources is no longer adequate to satisfy the rational allocation demands of urban development concerning the water and soil resource framework. To enhance the efficiency of utilizing water and land resources comprehensively and the rationality of the joint allocation of these resources, this paper presents a comprehensive analysis of the eco-economic system of water and land resources, encompassing six key aspects: system emergy flow, water resources subsystem, land resources subsystem, economic subsystem, ecological subsystem, and social subsystem. By considering three types of land use (construction land, agricultural land, and unused land), we constructed a sustainable evaluation index system for the eco-economic system of water and land resources based on the emergy theory. We employ the emergy theory analysis method to provide a comprehensive assessment of the sustainable development status and development trend of the Luoyang City from 2011 to 2020. The results show that Luoyang belongs to the consumer economy and the development of water and soil resources of the ecological economic system in Luoyang is in a critical state of unsustainable and mild sustainability from 2011 to 2020.

Quantifying multi-dimensional services of water ecosystems and breakpoint-based spatial radiation of typical regulating services considering the hierarchical clustering-based classification

This study proposes a set of water ecosystem services (WES) research system, including classification, benefit quantification and spatial radiation effect, with the goal of promoting harmonious coexistence between humans and nature, as well as providing a theoretical foundation for optimizing water resources management. Hierarchical cluster analysis was applied to categorize WES taking in to account the four nature constraints of product nature, energy flow relationships, circularity, and human social utility. A multi-dimensional benefit quantification methodology system for WES was constructed by combining the emergy theory with multidisciplinary methods of ecology, economics, and sociology. Based on the theories of spatial autocorrelation and breaking point, we investigated the spatial radiation effects of typical services in the cyclic regulation category. The proposed methodology has been applied to Luoyang, China. The results show that the Resource Provisioning (RP) and Cultural Addition (CA) services change greatly over time, and drive the overall WES to increase and then decrease. The spatial and temporal distribution of water resources is uneven, with WES being slightly better in the southern region than the northern region. Additionally, spatial radiation effects of typical regulating services are most prominent in S County. This finding suggests the establishment of scientific and rational intra-basin or inter-basin water management systems to expand the beneficial impacts of water-rich areas on neighboring regions.

Hidden Costs Associated with Smallholder Family-Based Broiler Production: Accounting for the Intangibles

The contractual relationship between the processing firm and the broiler smallholder presents incessant conflicts of interest and inequality due to technical and economic discrepancies, leading to an undervaluation of the producers’ remuneration. This study aims to deepen the discussion on searching for a more balanced monetary exchange between processing firms and broiler smallholders based on scientific aspects. For this, the emergy theory and its concepts are used while considering a representative broiler production system at Concórdia, Brazil. The results indicate the importance of including cultural information in the emergy-based model calculation, which achieved the highest emergy contribution (~63%; transformity = 1.73 × 108 sej/J) for the broiler smallholder. On the other hand, the cultural information was not sufficient to increase the sustainability of the broiler production system. The results show an imbalance in the monetary exchange between the processing firm and broiler smallholder from both perspectives (the economic and emergy-based ones), which indicates higher values (USD 0.32/broiler and EmUSD 1.62/broiler) than the practiced payment value of USD 0.24/broiler. Evaluating the “(eco)cost” from an emergy-based accounting perspective recognizes that production depends not only on tangible physical resources but also on knowledge, skills and information (“iceberg of value” thinking). Policy and decision makers must therefore consider the promotion of public policies that subside initiatives, including social and environmental welfare programs.

Coupled patterns of natural and anthropogenic resources in typical ecosystems in coastal areas of China

The coastal area of Yancheng, China, is one of the hotspots for ecological research. Under the coupling of human and natural ecosystems, the region has gradually evolved into a coexistence of aquatic, agricultural and mudflat ecosystems. What are the patterns of natural and artificial resource inputs and patterns of change in ecosystems? How can ecological flows be analyzed at a uniform scale? Here, we selected six typical local ecosystems, namely, rice‒wheat for enterprises (RWE), rice‒wheat for smallholder households (RWS), chrysanthemum‒wheat (CW), fish polyculture (FP), juvenile crab farming (JF) and clam polyculture (CP), and analyzed their energy flow flux and sustainability based on emergy theory. The results showed that anthropogenic resource inputs were higher than natural resource inputs in all ecosystems, and the inputs of aquatic ecosystems were greater than those of agroecosystems. The greatest total input was 2.0 E+17 seJ/ha/yr for FP, and the lowest was 1.9 E+16 seJ/ha/yr for RWE. The proportions of renewable and artificial inputs for RWE, RWS, CW, FP, JF and CP were 32.8% vs. 96.1%, 40.3% vs. 96.5%, 34.7% vs. 97.0%, 32.6% vs. 99.4%, 55.1% vs. 98.5%, and 62.5% vs. 98.6%, respectively. The highest input to agroecosystems was nitrogen fertilizer, while in JF and CP, it was water, and feed (63.3%) accounted for the highest percentage of input in FP. JF and CP had lower environmental loads and higher sustainability than other ecosystems, but this still represents a high input compared to agroecosystems. Human-led resource coupling profoundly affects ecosystem sustainability, and various thresholds of energy use and ecological sustainability need to be studied in depth. Continuous exploration of methods and mechanisms for the maintenance and evolution of ecosystems with low total inputs and low inputs of non-renewable resources can contribute to high-quality sustainable development of an area or region.

Evaluation of water resources sustainable development in karst area based on the improved emergy ecological footprint model: A case study of Yunnan Province

Abstract This study combined emergy theory with water ecological footprint to analyze and evaluate the sustainable development status of water resources in Yunnan Province from 2012 to 2021. The water pollutant account and the water product account were supplemented to the water ecological footprint. The results showed that the water resources in Yunnan Province were generally in an ecological deficit during the study period, but their absolute values were very small. The ecological pressure index of water resources was high, while the sustainable utilization index of water resources was low, indicating that the water resources were in a state of unsustainable utilization. However, the emergy ecological footprint of water resources and the emergy ecological footprint of water resources of 10,000 Yuan GDP showed a decreasing trend, and the eco-economic coordination index of water resources was relatively high, indicating that the water resources will show a sustainable development trend in the future. The sustainable development of water resources was influenced by both natural ecological factors and social factors. Therefore, suggestions such as improving the utilization rate of water resources development, developing a green low-carbon economy, preventing and controlling water pollution, and protecting the water environment are conducive to promoting the sustainable development of water resources.

Assessment and Suggestions on Sustainable Development of Regional Ecological Economy Based on Emergy Theory: A Case Study of Henan Province

A rapid development in regional economy is often accompanied by an increase in energy consumption and the intensification of environmental pollution, which brings great pressure to the social economy and the natural environment. In order to solve the integrated problem of economic, social, and natural factors, we propose an evaluation method for the sustainable development of the regional economy, based on emergy. By analyzing the statistical data of Henan’s economic development from 2010 to 2018, an evaluation index system of regional eco-economic sustainable development was constructed based on four aspects: natural subsystem, economic subsystem, social subsystem, and sustainable development index. The index system was then used to measure and comprehensively evaluate the sustainable development of the ecological economy and the environmental friendliness of Henan Province. The assessment results showed that the emergy self-sufficiency rate decreased, indicating decreased self-sufficiency. Moreover, the environmental load rate was high, indicating high environmental pressure. The emergy currency rate declined with a rise in the emergy investment rate, indicating economic growth. Additionally, the population carrying capacity was consistently > 1, indicating that the population was overloaded. Collectively, the emergy-based evaluation method of regional economic sustainable development in this study provides a comprehensive and scientific evaluation framework, which can help decision makers and researchers better understand and evaluate the problems brought about by the rapid development of regional economy, and provide targeted decision making suggestions. It includes four sub-systems: natural, economic, social, and sustainable, which have important theoretical and practical significances, while also serving as a useful reference for the evaluation of the sustainable economic development of similar regions.

Does economic agglomeration affect the sustainable intensification of cultivated land use? Evidence from China

The sustainable intensification (SI) of cultivated land use (CLU) is important for achieving global sustainable development goals (SDGs). However, in the rapid advancement of agglomeration economies, it remains unclear whether economic agglomeration (EA) affects SI. Combined with emergy theory, this study utilized socioeconomic and natural environment data from 31 provincial administrative regions from 1990 to 2017 to evaluate the SI level in China. It further analyzed the impact of EA on SI using a spatial econometric model that includes mediating effects. The results showed that the EA level in China continued to rise, whereas the SI level continued to decline from 1990 to 2017. The mediating effect analysis showed that fiscal support for agriculture and agricultural labor productivity have a suppression effect of |−4.186|% and |−2.002|% in the local region, while cultivated land-use intensity has partial mediation of 6.350% in the local region; and agricultural labor productivity has a suppression effect of |−4.680|% on the surrounding region, while cultivated land-use intensity has stronger partial mediation relative to the local region, even up to 10.402% on surrounding regions. This implies that the impact of EA on SI involves complex paths and spatial differences. This study provides a better understanding of the reasons for the continuous decline in the SI in agglomeration-type economic development and feasible policy proposals.

Suitable water surface area of the tail lake under the constraint of water diversion scheme in arid areas based on emergy theory

Study regionThe East Juyan Sea (Inner Mongolia, China) Study focusMaintaining a certain water surface area in the East Juyan Sea is the main sign of the success of the Heihe River water diversion. However, under the realistic constraint of limited water resources, the maintenance of the lake's water surface area and the oasis ecological water are in conflict. Through comprehensively considering various factors such as ecology, economy, and water resources, this study focused on the relationship between the East Juyan Sea's ecological service value and water surface area, which was investigated with emergy theory. Meanwhile, based on the status of local water resources and the principle of water diversion, the suitable water surface area of the East Juyan Sea's was given. New hydrological insights for the regionThe results indicated the optimal water surface area of the East Juyan Sea is approximately 40 km2. In addition, we can observe that the value of ecological services of a specified area increases infinitely with the expansion of its water surface area. But, within a certain threshold value, the amount of its value will become stabilize. Below or beyond this threshold, the value of regional ecological services will increase at a faster rate. However, the larger is not always better. The larger the water surface area, the easier it is to create competition for water with the oasis vegetation, which will be detrimental to the ecological health and stability of this region. Thus, the appropriate water surface area needs to be determined comprehensively by considering various factors such as ecology, economy, and water resources.

Sustainability Assessment of Urban Waterscape Belt Ecological Reconstruction Based on LCA–Emergy–Carbon Emission Methodology

Rivers play a key role in regulating urban ecology, which can improve urban climate while slowing the heat island effect. As one of embodied energy in the field of ecology, emergy theory can be used to quantitatively evaluate the ecological characteristics of a system. This will help to further explore urban ecological sustainability in this article. In this study, four ecological riverbank reconstruction projects have been executed to restore the ecology along the banks of the Jinchuan River in Nanjing, China, which focus on the key river–lakeside and waterfront space in the main urban area. The LCA–emergy–carbon emission method was applied through a series of indicators, including emergy indexes and carbon emission indicators. It is important to distinguish prior research, and few have utilized this approach on urban waterways and waterscapes. The results illustrate that the reconstruction system has obvious improvement significance to the whole river ecology. This change can also be seen when using LCA–emergy analysis. In a 20-year cycle, the emergy of the material production stage and maintenance phase account for a major emergy share, followed by the construction stage, transportation process, and design process stage. The sustainability (ESI indicator) has been improved after carrying out the reconstruction projects. By choosing water and gravel as the primary material, the carbon emission can be reduced. The water treatment process accounts for the vast majority of carbon emissions. Secondly, gravel also plays an important role in carbon emission. Finally, an improved measure (clean energy reuse) was conducted to enhance the ecology of the reconstruction projects and obtained a significant ecological sustainability boost.

Multi-dimensional interest game between reservoir and city stakeholders in the Yellow River Basin: a case study of the lower reaches

Reservoirs in sediment-laden rivers can bring multiple benefits, and the calculation and redistribution of these considerable benefits are the premises to ensure the efficient operation of reservoirs. Firstly, the benefits of social economy, ecological environment, flood discharge, and sediment transport under the joint operation of reservoirs are uniformly measured based on the emergy theory. Secondly, the stakeholders are divided into reservoir and city groups. A two-tier gains allocation model is established based on the Nash bargaining model and multi-attribute decision making theory. Finally, taking the lower reaches of the Yellow River, Sanmenxia Reservoir, and Xiaolangdi Reservoir as cases, the multi-dimensional benefits of reservoirs under the two operation modes in the face of typical floods are calculated, and the gains are distributed among stakeholders. The results show that: (1) Although the overall benefit of the system is optimal under one scheduling mode, 7/17 of the stakeholders prefer another mode. (2) Comparing the two operation modes of the reservoir group, it is found that XLD and SMX can improve the overall benefit of 4.12E + 09yuan at the cost of their sediment discharge benefits of 3.08E + 09yuan and 2.82E + 06yuan. (3) After gains distribution, the profit of all stakeholders can be optimized to varying degrees. This study broadens the dimension of benefit accounting under the joint operation of cascade reservoirs and the category of stakeholders in the gain allocation, which is conducive to promoting the ecological protection and sustainable development of sediment-laden rivers.

Spatiotemporal evolution of water ecological footprint based on the emergy-spatial autocorrelation method.

To quantify and analyze the human demand for water resources and the available supply of water resource systems, this study combined emergy analysis and spatial autocorrelation analysis to establish a quantification and analysis system for water ecological footprint (WEF). First, the emergy theory of ecological economics and WEF were combined to propose an emergy quantification method for WEF and water ecological carrying capacity (WEC). Based on the spatial autocorrelation method, three-dimensional ecological footprint indicators (footprint size and depth) were introduced to analyze the spatial correlation and spatial aggregation of capital flow occupation and capital stock consumption in the water resource system. Using the Yellow River Basin (YRB) as the study area to verify the applicability of the WEF quantification and analysis system based on the emergy-spatial autocorrelation method, the following results were obtained. (1) From 2003 to 2018, the per capita WEF of the YRB generally showed a slow growth trend. (2) Compared to the upper and lower reaches of the YRB, the middle reaches had a higher WEF, and the WEC of the YRB was generally high in the west and low in the east. (3) Utilization of the water resources capital in the basin was generally unsustainable. It is necessary to take measures to promote rational allocation and efficient utilization of water resources for the coordinated development of society, the economy, and the environment in the YRB. (4) The emergy-spatial autocorrelation method is applied to basin/region water sustainability studies for decision makers.

Emergy evaluation of biogas production system in China from perspective of collection radius

Biogas production has become one of the main renewable energy utilization modes in Chinese rural areas. In this study, emergy theory was employed to assess the ecological sustainability of biogas production system based on the case of Weilai energy company. Emergy radius formulas derived from biogas production characteristics were constructed to illustrate the relationship between the degree of system development and biomass supply distance. The calculated emergy results showed that the biogas production system required an average of 1.98 E+14sej emergy inputs in the process of utilizing one-ton agricultural waste. And the emergy indicators implied that the system had a low degree of social resource input and environmental loading, indicating that the system could keep high output efficiency and ecological sustainability. The biomass recycling distance (9.93 km) which was calculated from emergy radius demonstrated better ecological performance and higher waste utilization degree than that of economic recycling distance (7.57 km). Biomass recycling distance based on emergy theory would provide a comprehensive understanding for the biogas production development.

Quantitative study on eco-economic compensation for water rights trading along the South-to-North Water Diversion Project in China

Abstract The completion of the South-to-North Water Diversion Project (SNWDP) of China has necessitated water rights trading along the route. However, water rights trading generally results in an externality loss for the seller. The scientific compensation of water rights trading should be considered from the aspects of economy, society and eco-environment. In this study, we quantified the water rights trading compensation along the route from economic, social, and environmental aspects, using a method based on emergy theory. Taking Pingdingshan-Xinmi water rights trading as an example, the eco-economic compensation of Pingdingshan was quantified and analyzed. The results showed that the impact of water rights trading on Pingdingshan was mainly social and ecological in the short term, and the average social and ecological compensation was 0.027 ¥/m3 and 0.32 ¥/m3 respectively. As the economic loss caused by water shortage becomes more prominent in the long term, the social, ecological and economic compensation were shown to be 0.028 ¥/m3, 0.30 ¥/m3 and 4.55 ¥/m3 respectively in 2030. The economic impact of water rights trading on the water seller will become more and more obvious, and reasonable compensation is the key to the sustainable development of the water market.

Emergy analysis-based study of the sustainable development of Kunming’s urban eco-economic system

ABSTRACT We studied Kunming’s urban eco-economic system’s evolution from 2009 to 2018, using the emergy theory and method; with the entropy evaluation method, we analyzed the system’s natural, social and economic subsystems to know its sustainable development capacity. The results show that the system’s emergy structure has clearly improved, and its renewable resources’ emergy has been rationally employed. The environment load ratio, after reaching its peak in 2011, has been decreasing, and the environment stress has becoming lower year by year, as is conducive to sustainable development. Its eco-economic system, however, is highly dependent on the internal resources; its emergy self-sufficiency ratio indicates that it does not see sufficient utilization of imported emergy and feels excessive stress on its internal resources. It witnesses relatively high emergy intensity. The current population is about twice of its renewable resources’ population carrying capacity, and its dramatically growing population is presenting even high pressure on its social subsystems. This indicates that the living standard per capita in Kunming is lower than the national average. All of these factors will hinder the sustainable development of Kunming’s urban eco-economic system. Our analysis of attribute classification shows that it is more appropriate to calculate the tourist revenue by taking into account export emergy. At the same time, the analysis results of sustainable development emergy indexes obtained by ESI, EISD, euehi, euehi’ and entropy method are compared, which shows that the entropy method is able to better reflect the dynamic changes of the sustainable development capacity of its urban eco-economic system because it introduces all indicators of social, economic and natural subsystems for evaluation. In a word, sustainable development capacity represents the outcome of tradeoff and coordination of the three subsystems of society, economy and nature, and we can formulate corresponding strategies based on the above research findings.

Sustainable Management and Environmental Protection for Basin Water Allocation: Differential Game-based Multiobjective Programming

It is important to manage water resources via emergy theory and its implementation mechanism for water dispatching while considering both economic development and environmental needs. The contribution of this paper is to propose a multi-objective dynamic differential game that can determine the optimal tax rate (OTR), optimal trading quantity of water (OTQW) in each province, and optimal bargain price (OBP) to balance resource consumption, economic development and environmental protection. Considering the sustainability of the ecological environment, the quantification of negative sewage value and net carbon emission constraints are introduced into the water allocation. To maximize the target revenue functions, minimize the net carbon emission constraints and obtain sustainable equilibrium solutions in this triple-level game, the costate function, Hamiltonian, and Lagrangian multiplier method are introduced. Then, a water dispatching structure is constructed for error correction between the predicted and actual runoff of the YRB. Taking the Yellow River Basin as an example, the validity of the proposed framework and solution method were verified under different hydrological years, with 6.5% ~ 9.1% higher economic benefits than other schemes and 4.3% ~ 5.9% lower net carbon emissions than other schemes. Compared to previous studies, this scheme can better meet the requirements of sustainable development and environmental protection.

Solution of issues in emergy theory caused by pathway tracking: Taking China's power generation system as an example

Emergy theory is effective to evaluate sustainabilities by tracking all the resources of a product formation process and converting them to solar emergy baseline. Emergy transformity (Tr) is essential to obtain the emergy value of a product. However, a secondary product coming from different production pathways will have various Trs, making it difficult to select a representative Tr when it is used as an input of other systems. Different methods for representative Tr are used in previous studies without considering the characters of different pathways. A method to obtain representative Tr is proposed in this study by classifying the pathways for a secondary product into the technological-impacted-systems and environmental-impacted-systems with the advanced and average values adopted as the representative Trs, respectively. Based on the market share and representative Tr of each pathway, the weighted average value could be obtained as the representative Tr of the product. The on-grid power generation system of China is taken as a case study. The nuclear and coal-fired power generation systems belong to technological-impacted-systems, while the renewable power generation systems belong to environmental-impacted-systems. According to the proposed method, the representative Tr of electricity generated in China is 1.13 × 105 sej/J.