Accounting Of CO2 Emissions Research Articles

Accounting Method and Indicators of Multilevel CO2 Emissions Based on Cost During Construction of Shield Tunnels

With the rapid expansion of shield tunnel projects in China, precise accounting of CO2 emissions throughout the entire process is essential for advancing green and low-carbon construction practices. This paper introduces an innovative CO2 accounting methodology utilizing a cost-based carbon emission coding system. It adopts a multilevel approach to carbon emission accounting, aligned with this coding system, which facilitates a detailed examination of carbon emission ratios and characteristics across various construction techniques. The analysis includes six typical shield tunnel projects varying in diameter, focusing on sub-projects to scrutinize CO2 emissions and establish specific indicators. The findings indicate that CO2 emissions per 10,000 yuan of investment, approximately 30.25% (or 3025 kgCO2e/10,000 yuan), are more consistent than those per unit of length. Moreover, the study highlights differing CO2 emission trends among sub-projects compared to whole tunnel projects, assessing emission indicators and distribution patterns in four sub-projects: shield excavation, segmental lining, internal structure, and tunnel reinforcement. From these findings, the paper suggests more precise and tailored strategies for CO2 reduction. This research provides a theoretical basis for future construction planning and carbon management strategies.

Reducing Measurement Costs of Thermal Power: An Advanced MISM (Mamba with Improved SSM Embedding in MLP) Regression Model for Accurate CO2 Emission Accounting.

Current calculation methods for the carbon content as received (Car) of coal rely on multiple instruments, leading to high costs for enterprises. There is a need for a cost-effective model that maintains accuracy in CO2 emission accounting. This study introduces an MISM model using key parameters identified through correlation and ablation analyses. An Improved State-Space Model (ISSM) and an IS-Mamba module are integrated into a Multi-Layer Perceptron (MLP) framework, enhancing information flow and regression accuracy. The MISM model demonstrates superior performance over traditional methods, reducing the Root Mean Square Error (RMSE) by 22.36% compared to MLP, and by 9.65% compared to Mamba. Using only six selected parameters, the MISM model achieves a precision of 0.27% for the discrepancy between the calculated CO2 emissions and the actual measurements. An ablation analysis confirms the importance of certain parameters and the effectiveness of the IS-Mamba module at improving model performance. This paper offers an innovative solution for accurate and cost-effective carbon accounting in the thermal power sector, supporting China's carbon peaking and carbon neutrality goals.

Improving Volume and Biomass Equations for Pinus oocarpa in Nicaragua

We present a new set of equations for tree level volume and aboveground biomass estimation for ocote pine (Pinus oocarpa Schiede ex Schltdl). These equation systems are the first developed for this species in Nicaragua. The first system includes a taper function, a merchantable volume equation, and volume equations for stem, coarse branches, and whole trees. The second system estimates whole tree and individual tree component biomass (stem wood, bark, branches, and needles). Data from 112 sampled trees were used for models’ development. Seemingly Unrelated Iterative Regression and the Generalized Method of Moments were used to simultaneously fit the volume and biomass equations systems, respectively; both methods ensure additivity and compatibility between equations. Weighted regression and a second-order continuous autoregressive error structure were used to correct heteroscedasticity and autocorrelation within the hierarchical dataset. The predictive power of the new proposed equations is higher than the currently used models for P. oocarpa in the country. These equation systems represent a scientific advancement that will enhance forest inventories, optimize timber management of the species, and facilitate accurate monitoring of forest carbon dynamics. Additionally, the new equations will contribute to a more precise accounting of CO2 emissions from the country’s forestry sector.

CO2 emission accounting and emission reduction analysis of the steel production process based on the material-energy-carbon correlation effect.

This paper develops a process-level carbon emission calculation model for iron and steel enterprises through the carbon emission mechanism of the whole production process. The relationship between material, energy and carbon flows is considered and combined. The carbon emissions of enterprises are divided into industrial emissions and combustion emissions, and the indirect emissions of purchased intermediate products and electricity purchased from the grid are also considered. Carbon emission targets and corresponding emission reduction strategies are formulated at the enterprise and process levels. For example, consider an iron and steel enterprise. The different types of carbon emissions are accounted for, with their reduction potential analysed based on the carbon material flow analysis method. The results show that the carbon emission of this enterprise is 1930.87 kgCO2/t (CS), and the combustion emission caused by energy flow is the main contributor to the enterprise's carbon emission, accounting for 57.02% of the total emission. The carbon emission during iron-making accounts for 69.06% of the entire process and is critical in any carbon emission reduction of the enterprise. Among them, process emissions from the blast furnace process account for 81.79% of industrial emissions of the whole process, which is 356.51 kgCO2/t (CS), and is the main challenge of low carbon transformation in this extensive process. This study highlights that increasing the integrated steel-making scrap ratio and electric furnace steel production can break through the existing emission reduction limits. A 65.02% carbon emission reduction can be achieved, and using green electricity can reduce emissions by 24.15%. Reasonably determining the amount of purchased coke and paying attention to the high-value recycling of byproduct gas resources in the plant are essential to achieve low-carbon economic development of steel.

Traffic ahead: Navigating the road to carbon neutrality

The journey to carbon neutrality will require trillions of dollars of capital investment over many years. Analytical models based on foresight offer guidance, but an overreliance on them can lead to a myopic focus on a single pathway. Some argue that the solution is to develop higher-resolution models, fed with increasingly granular data. Here, we note that real-time feedback is an important and underappreciated complement to this approach.We discuss how nations and corporations are currently embarking on the energy transition with the equivalent of a high-level map. The ambition is clear, but there is a lack of confidence in the best route. Routing options and conditions are changing rapidly. We outline the features of a navigation app for the energy transition that offers real-time, actionable guidance for the energy transition would be hugely beneficial. The essential function of such an app would be to collect, secure, process, and present data in a way that can support decisions by relevant actors. Such a capability would require three essential elements: route topology awareness with high-resolution details of the benefits and costs of different decarbonization options; data platforms that provide insight into the real-time situation; and trade-off tools that readily convey accurate, up-to-date, and easily-interpretable estimates of switching costs. These elements exist at varying levels of maturity, and improvement and integration is needed to deliver the utility and convenience of a road travel app.This Perspective draws on our collective experience mapping paths to carbon neutrality for the Princeton Net-Zero America study and one of China's largest energy companies (China Energy) to develop the idea of navigation apps for the energy transition. Starting with a resolved accounting of CO2 emissions, we illustrate the importance of accounting for differing motivations and leverage among actors. We discuss the essential features of a navigation app and show how progress in these areas can help address bottlenecks in large-scale clean energy deployment. We conclude with a call for increased collaboration with tech companies to accelerate development of these capabilities.

Emission accounting and drivers in 2004 EU accession countries

The ten countries that joined the European Union (EU) in 2004 (Cyprus, Czechia, Estonia, Hungary, Lithuania, Latvia, Malta, Poland, Slovakia, and Slovenia) have experienced faster economic growth and slower declines in energy consumption than traditional EU members. As designing of low-carbon policies requires accurate CO2 emission accounting, this study describes the evolving trajectories of CO2 emissions from 2005 to 2017 of 2004 EU accession members by providing detailed emission inventories by 28 types of energy and 47 socioeconomic sectors. We further quantify the contributions of four socioeconomic drivers (i.e., economic growth, energy structure, carbon intensity, and energy intensity) to the emission changes. The results show that the total CO2 emissions of the ten countries decreased by 7.50% from 2010 (506.81 Mt) to 2016 (468.78 Mt), which is lower than the average decline rate of other EU members (10.52%). Although the effect of economic growth contributed the most to emission increase (15.44%), it is completely offset by the decline in carbon intensity (-18.82%). We also discuss potential roadmaps towards carbon neutrality by designing 33 scenarios based on the European Union Low-Carbon Development Map 2050. We find that carbon neutrality cannot be achieved unless the share of renewable energy sources reaches 60% and more than half of existing coal and gas power plants are upgraded to Carbon Capture Storage (CCS) technology. These changes require the implementation of both short-term and long-term strategies.

Spatial and structural characteristics of CO2 emissions in East Asian megacities and its indication for low-carbon city development

The identification of CO2 emissions in megacities is vitally important to promote a transition to low-carbon city. This study aims to analyze the CO2 emission characteristics and spatial distribution in megacities among different countries, which is important for climate change mitigation. In this study, 12 megacities from China, Japan, and South Korea were selected as typical case studies for analysis. Results show that Chinese cities’ CO2 emissions are among the top four cities studies and are much higher when compared to the other sample cities in Japan and South Korea. Chongqing, Incheon, Tianjin, and Shanghai were the top four cities with the highest carbon intensity. The spatial distribution of urban carbon emissions varies widely. In Seoul, Tokyo Metropolis, and Beijing, 90% of carbon emissions are concentrated on 74.17%, 55.95% and 8.93% of the land area, respectively. The results of the driving forces and emission reduction targets analysis indicate that the three countries face different challenges and there are different action plans in each city accordingly. This study proposed the carbon emissions reduction targets and countermeasures in different industrial sectors, including an increased rate of the standardization of city CO2 emission accounting systems and the decarbonization of the power industry, among others. These countermeasures will not only contribute to the analysis of CO2 emissions but will also promote to the low-carbon city development and encourage the realization of urban sustainable development goals.

CO2 emissions and their spatial patterns of Xinjiang cities in China

City-level CO2 emission accounting is necessary to identify the different energy circumstances among all cities. However, due to a lack of data, energy consumption and emission statistics are not well documented. Focusing on the industrial production using fossil fuels, our work provides the first detailed city-level estimation of production-based sectoral CO2 emissions in the Xinjiang Uygur Autonomous Region. In 2010, 15 cities in Xinjiang emitted a total of 304.06 million tonnes CO2, and 97.7% of those emissions were related to fossil fuel combustion (i.e. energy-related emissions), with the remaining 2.3% from industrial processes associated with the production of cement (i.e. process-related emissions). The consumption of raw coal and crude oil were the main sources of Xinjiang’s emissions (50.3% and 23.0%, respectively), whereas ‘petroleum processing and coking’ and ‘power and heat production’ were the two sectors that contributed the largest emissions at 32.6% and 27.9%, respectively. The cities in Xinjiang presented considerable variations in the total CO2 emissions and emissions per capita. The emissions intensity and emissions per capita shared similar distributions, and the emissions are significantly spatial autocorrelated. Cities whose economies relied on emission-intensive pillar industries and/or energy mainly sourced from raw coal tended to have high emissions per capita and high emissions intensities. Those cities included Altay, Changji, Hami and Shihezi. We also examined the time-series emissions of Urumqi, the largest city, from 2005 to 2015. Urumqi presented a generally rising trend in CO2 emissions over the decade, with emissions increasing by 324.2%. The major driving sector was ‘power and heat’, which showed increases in the total CO2 emissions and percentage of Xinjiang’s emissions. Based on the findings, policy recommendations for emission reductions and low-carbon development for the cities in Xinjiang are provided, including adjusting the energy structure and introducing multiple industries.

Drivers of CO2 emissions from power generation in China based on modified structural decomposition analysis

Currently, over 20% of global electricity and 30% of global CO2 emissions from fuel combustion are generated in China. Understanding the driving forces of CO2 emissions from power generation is critical for both decarbonizing the power sector and achieving national carbon reduction targets. The objectives of this study were to identify critical driving forces behind changes in CO2 emissions from the power sector and to propose appropriate decarbonization pathways. First, the generation and demand structures of the power sector were introduced into a CO2 emission accounting model and decomposition analysis. Instead of traditional input–output analysis, structural decomposition analysis modified using a power transmission table was used to investigate the impacts of five driving factors of CO2 emissions from China’s power generation. The five driving factors comprised the proportion of thermal power, power generation technology, power generation structure, power demand structure and power demand, whereby the latter was divided further into nine detailed parts. Considering five regional power grids in China, the contributions of these factors were analyzed at both national and regional level. The results showed that the majority of the increase in CO2 emissions during 2007–2012 could be attributed to electricity generation (96.2%) driven by changes in power demand, which should be the key to power sector decarbonization. By contrast, 30.7% of emissions were offset by changes in the proportion of thermal power and technology, demonstrating the obvious effects of China’s policy on clean energy transition. Additionally, all power grids exhibited an increase in CO2 emissions from electricity generation, with the east and central grids accounting for 64% of the national increase. Power transmission structure had only a small impact on CO2 emissions from power generation. By using the electricity transmission table, we modified SDA to overcome the time lag issues and eliminate the reliance on IO data, and continuous annual data rather than aggregated five-yearly data can be used to capture the structural effects, thus providing more precise results for the driving forces of emission changes. Our case study shows that there is huge potential in extending the IO-based SDA method to other trade-related studies.

Reply to the Comment by Zhang and Fang (2019) on Consumption-Based Versus Production-Based Accounting of CO2 Emissions

Zhang and Fang (2019) criticize our finding (Franzen and Mader 2018) that there is (on average) no carbon leakage from developed to developing countries. In the paper we show that countries’ GDP per capita is statistically not related to the ratio of consumption-based (CBA) to production-based (PBA) accounting of CO2 emissions. Hence, the ratio of the two accounting schemes does not differ between richer and poorer countries or, put differently, does not depend on a country’s GDP per capita. Zhang and Fang (2019) have two concerns with our paper: First, they believe that we should have used the Global Carbon Atlas (GCA) for both CBA and PBA and should not have mixed the data with the Emissions Database for Global Atmospheric Research (EDGAR); we used the EDGAR to obtain countries’ PBA and the GCA to obtain their CBA. Second, the authors argue that we should not have used the ratio of CBA to PBA but the difference of CBA – PBA for our analyses. In what follows, we respond to both concerns.

Consumption-based accounting of CO2 emissions in the sustainable development Goals Agenda

ABSTRACTIn 2017 the paper ‘The Sustainable Development Oxymoron: Quantifying and Modelling the Incompatibility of Sustainable Development Goals’ was published, showing that there is a conflict between socio-economic development goals and ecological sustainability goals using cross-country time-series data. The authors looked at production-based CO2 emissions to measure and model the 13th SDG goal addressing climate change. Their models showed that production-based CO2 emissions were stalling or even decreasing in rich countries, which suggests that other countries are also likely to see stalling and decrease in their CO2 emissions once they become rich. However, this conclusion can be challenged when accounting for consumption-based CO2 emissions rather than production-based CO2 emissions. In this follow-up paper, we re-run some of the analyses performed in the original paper making use of consumption-based CO2 emissions. The analysis confirms the inherent SDG conflict between socio-economic and ecological SDGs. But, this new analysis demonstrates that from a consumption perspective the trend of stalling or decreasing CO2 emissions is reversed, with natural depletion costs being exported to poorer countries. Despite this new perspective on CO2 emissions, the conflict between SDG goals can still be avoided by making investments in public health, education and renewable energy, as suggested in the original paper.

Comparative analyses of different biogenic CO2 emission accounting systems in life cycle assessment

The biomass-derived CO2 emission is usually treated as neutral to climate change. However, due to the stay of biomass-derived CO2 in the atmosphere, many researchers believe that biomass-derived CO2 also has climate change benefit. Therefore, many methods to account the global warming potential of biomass-derived CO2 (GWPbio) were proposed. Based on those new methods, we developed an accounting system for climate change impact of biomass utilization in this study, and compared it with the conventional accounting system which follows the carbon neutral assumption. A case study of caragana-to-pellet bioenergy production system was simulated to test the performance of the GWPbio accounting system. The CENTURY model was used to simulate carbon dynamics of caragana plantation in the Loess Plateau in China, and life cycle assessment (LCA) model was developed to estimate the life cycle emissions of the caragana-to-pellet system. Attributed to short rotation of caragana plantation and fast biomass accumulation after harvest, the GWPbio values around 0.044 were obtained. When the GWPbio was applied to LCA, significant high life cycle CO2 emission was found in comparison to the conventional method. However, the GWPbio accounting system has lower positive climate change impact than the conventional accounting system in assessing the overall impact of biomass utilization. This indicated that the application of GWPbio accounting system would encourage the utilization of biomass and allow a fair comparison with fossil fuels. In the sensitivity analysis, we found the accounting system was sensitive to biomass accumulation and all the corresponding factor affecting biomass accumulation.

Consumption-Based Accounting of CO2 Emissions in the Sustainable Development Goals Agenda

In 2017 the paper Sustainable Development Oxymoron: Quantifying and Modelling the Incompatibility of Sustainable Development Goals (Spaiser et al. 2017) was published, showing that there is a conflict between socio-economic development goals and ecological sustainability goals using cross-country time-series data. The authors looked at production-based CO2 emissions to measure and model the 13th SDG goal addressing climate change. Their models showed that production-based CO2 emissions were stalling or even decreasing in rich countries, which suggests that other countries are also likely to see stalling and decrease in their CO2 emissions once they become rich. However, this conclusion can be challenged when accounting for consumption-based CO2 emissions rather than production-based CO2 emissions. In this follow-up paper, we re-run some of the analyses performed in the original paper making use of consumption-based CO2 emissions. The analysis confi rms the inherent SDG conflict between socio-economic and ecological SDGs. But, this new analysis demonstrates that from a consumption perspective the trend of stalling of decreasing CO2 emissions is reversed, with natural depletion costs being exported to poorer countries. Despite this new perspective on CO2 emissions, the conflict between SDG goals can still be avoided by making investments in public health, education and renewable energy, as suggested in the original paper.

Consumption-based versus production-based accounting of CO2 emissions: Is there evidence for carbon leakage?

Lately, a controversial debate has evolved regarding consumption-based accounting (CBA) versus production-based accounting (PBA) of CO2 emissions. So far, the debate has been predominately theoretical and has inspired only a few empirical studies. In this article, we compare production-based versus consumption-based emissions, and for the first time analyze reasons for the differences. In particular, we focus on whether there is evidence for carbon leakage from developed to developing countries. We use the newest available data for 110 countries and analyze whether there are differences between OECD and non-OECD members. Furthermore, we compare the within-country differences for the time span of 1997 to 2011 via fixed effects panel regression models in order to investigate whether increases in GDP per capita result in higher imported emissions. The results suggest that for most countries the differences depending on accounting schemes are small. Furthermore, we find no evidence for carbon leakages. In particular, the ratio of CBA to PBA is not driven by OECD membership or GDP per capita. Instead, the ratio is greater for countries with high energy efficiency and high import rates. Given the small differences between PBA and CBA, we suggest keeping the production-based accounting of CO2 emissions.

Value-Added-Based Accounting of CO2 Emissions: A Multi-Regional Input-Output Approach

In the era of globalization and international trade, the production-based CO2 emissions accounting system, proposed by United Nations Framework Convention on Climate Change, can easily lead to a “carbon leakage” issue. Thus, the accounting of consumption-based carbon emissions and carbon emissions embodied in international trade has received considerable research attention. Nevertheless, researchers also indicated that the consumption-based principle has some weaknesses, for example, it leads the producers inert on reducing carbon emissions while gaining economic benefits. To share carbon emissions responsibilities between producers and consumers is widely recognized. So, setting an income-based emissions accounting method as to producer is a necessary complement for accounting national carbon emissions. This study promoted a model, called the value-added-based accounting of CO2 emissions method, to account for anthropogenic CO2 emissions within the context of the economic benefit principle. Based on the global multi-regional input-output table and national carbon emissions database, we calculated the national/regional carbon emissions based on the value-added accounting approach as well as the amount of global carbon emissions embodied in value-added chains. If the results are served as a supplement for calculating the amount of CO2 emissions reduction that a country is responsible for, problems such as carbon leakage and resistance to improving the energy efficiency of exporting sector may be solved, because all the supply chains emissions associated with the economic growth of a country would be considered.

Commitment accounting of CO2 emissions

The world not only continues to build new coal-fired power plants, but built more new coal plants in the past decade than in any previous decade. Worldwide, an average of 89 gigawatts per year (GW yr–1) of new coal generating capacity was added between 2010 and 2012, 23 GW yr–1 more than in the 2000–2009 time period and 56 GW yr–1 more than in the 1990–1999 time period. Natural gas plants show a similar pattern. Assuming these plants operate for 40 years, the fossil-fuel burning plants built in 2012 will emit approximately 19 billion tons of CO2 (Gt CO2) over their lifetimes, versus 14 Gt CO2 actually emitted by all operating fossil fuel power plants in 2012. We find that total committed emissions related to the power sector are growing at a rate of about 4% per year, and reached 307 (with an estimated uncertainty of 192–439) Gt CO2 in 2012. These facts are not well known in the energy policy community, where annual emissions receive far more attention than future emissions related to new capital investments. This paper demonstrates the potential for ‘commitment accounting’ to inform public policy by quantifying future emissions implied by current investments.

A life cycle carbon dioxide inventory of the Million Trees Los Angeles program

Purpose This study seeks to answer the question, “Will the Million Trees LA (Million Trees Los Angeles, MTLA) program be a carbon dioxide (CO2) sink or source?” Because there has never been a full accounting of CO2 emissions, it is unclear if urban tree planting initiatives (TPIs) are likely to be effective means for reaching local reduction targets. Methods Using surveys, interviews, field sampling, and computer simulation of tree growth and survival over a 40-year time period, we developed the first process-based life cycle inventory of CO2 for a large TPI. CO2 emissions and reductions from storage and avoided emissions from energy savings were simulated for 91,786 trees planted from 2006 to 2010, of which only 30,813 (33.6 %) were estimated to survive. Results and discussion The MTLA program was estimated to release 17,048 and 66,360 t of fossil and biogenic CO2 over the 40-year period, respectively. The total amount emitted (83,408 t) was slightly more than the −77,942 t CO2 that trees were projected to store in their biomass. The MTLA program will be a CO2 sink if projected 40-year-avoided fossil fuel CO2 emissions from energy savings (−101,679 t) and biopower (−1,939 t) are realized. The largest sources of CO2 emissions were mulch decomposition (65.1 %), wood combustion (14.5 %), and irrigation water (9.7 %). Conclusions Although trees planted by the MTLA program are likely to be a net CO2 sink, there is ample opportunity to reduce emissions. Examples of these opportunities include selecting drought-tolerant trees and utilizing wood residue to generate electricity rather than producing mulch.

Production and consumption accounting of CO2 emissions for Xiamen, China

Abstract Consumption accounting of urban greenhouse gas emissions is preferable to production accounting, because cities are open systems which depend on the import of large quantities of externally produced goods. In this paper we use environmental input–output analysis to construct CO 2 production and consumption accounting inventories for Xiamen, a rapidly developing coastal city in southeast China. We found that, in 2007, total emissions embodied in production were 21.8 Mt CO 2 , of which 17.1 Mt CO 2 were embodied in exports and 4.7 Mt CO 2 resulted from local demand on local production. If the large amounts of emissions embodied in the Xiamen reprocessing trade are excluded from the analysis, total imported emissions were 12.2 Mt CO 2 , consumption emissions were 16.9 Mt CO 2 , and Xiamen was a net exporter of 4.9 Mt CO 2 . Although Xiamen's rapid economic growth is dependent on large-scale flows of embodied emissions, most of these emissions are not produced or consumed within the city system.

BiotecVisions 2012, February

BiotecVisions 2012, February

Consumption-based accounting of CO 2 emissions

CO(2) emissions from the burning of fossil fuels are the primary cause of global warming. Much attention has been focused on the CO(2) directly emitted by each country, but relatively little attention has been paid to the amount of emissions associated with the consumption of goods and services in each country. Consumption-based accounting of CO(2) emissions differs from traditional, production-based inventories because of imports and exports of goods and services that, either directly or indirectly, involve CO(2) emissions. Here, using the latest available data, we present a global consumption-based CO(2) emissions inventory and calculations of associated consumption-based energy and carbon intensities. We find that, in 2004, 23% of global CO(2) emissions, or 6.2 gigatonnes CO(2), were traded internationally, primarily as exports from China and other emerging markets to consumers in developed countries. In some wealthy countries, including Switzerland, Sweden, Austria, the United Kingdom, and France, >30% of consumption-based emissions were imported, with net imports to many Europeans of >4 tons CO(2) per person in 2004. Net import of emissions to the United States in the same year was somewhat less: 10.8% of total consumption-based emissions and 2.4 tons CO(2) per person. In contrast, 22.5% of the emissions produced in China in 2004 were exported, on net, to consumers elsewhere. Consumption-based accounting of CO(2) emissions demonstrates the potential for international carbon leakage. Sharing responsibility for emissions among producers and consumers could facilitate international agreement on global climate policy that is now hindered by concerns over the regional and historical inequity of emissions.