Carbon Intensity Research Articles

A comparison of deflation methods for carbon footprint calculations using Japanese data

An embodied CO2 emissions intensity database estimated from input–output data at current prices is now available in Japan. This study compares two non-survey methods: The double-deflation (DD) method and an elaborated approach combining the DD method with the generalized RAS method to deflate an input–output table (IOT). We used these methods to estimate new datasets of embodied CO2 emission intensity data in Japan, utilizing Japan's IOTs for 2005, 2011, and 2015 at constant prices in 2015. Furthermore, we compare the estimated data of 367 commodity sectors for a specific year (2005 or 2011). The results reveal that the intensity for certain aggregated sector groups, such as non-ferrous metals and finance and insurance, exhibits higher uncertainty owing to the extreme price homogeneity assumption associated with the DD method. Consequently, we recommend that life-cycle-assessment practitioners use an open database when analyzing changes in the carbon footprint of products over time.

Enterprises’ Emissions Intensity and Financial Performance in Serbia: The Case Study of Wastewater

Untreated industrial and municipal wastewater is the key factor that leads to water pollution in Serbia. The aim of the paper is to examine the impact of environmental performance (using eco-intensity indicators) of enterprises on their profitability in the period 2011-2020 in Serbia in the area of wastewater. Apart from using the panel data technique in the paper, the Generalized Method of Moments (GMM) is also used to estimate the parameters in the model. The results demonstrate that if the eco-intensity indicator increases, the profitability of an enterprise increases significantly, whereas the profitability of an enterprise decreases with the increase in the size of an enterprise. According to the results of the evaluated model, the capital intensity variable has no influence on the profitability of an enterprise. Additionally, it has been determined that the coefficient with the eco-intensity indicator is quite large, indicating the poor eco-efficiency of Serbian enterprises in the area of wastewater.

How does digital finance reduce carbon emissions intensity? Evidence from chain mediation effect of production technology innovation and green technology innovation

The digitalization of finance drives economic development and plays a crucial role in energy conservation and carbon emission reduction. Utilizing carbon emissions data from 2011 to 2020, we find that digital finance development can mitigate carbon emissions intensity (CEI) by approximately 0.14 %. Then, we employ a diverse set of robustness and endogeneity tests to assess the reliability of the empirical findings. Moreover, the study delves into how digital finance impacts CEI through production technology innovation (PTI) and green technology innovation (GTI). The results indicate a positive effect of PTI on CEI. GTI exerts a negative influence on CEI. In addition, there is a chain mediation effect between PTI and GTI in the baseline path. Finally, the impact of digital finance on CEI exhibits apparent regional heterogeneity.

Integrated e-Methanol and Drop-in Fuels Hydrothermal Liquefaction Platform-Techno-Economic and GHG Emissions Assessment for Grid-Connected Plants under Flexible BECCU(S) Operation.

This study examines the combined production of drop-in fuels and methanol using hydrothermal liquefaction (HTL) as a technological basis in the context of bioenergy and power-to-X (PtX) applications. Given the increasing need for flexibility in a system dominated by fluctuating renewable power, we evaluated flexible methanol operation as a strategy to harness global greenhouse gas (GHG) emissions in a grid-connected HTL setup. In this operation, the biogenic CO2 destination is alternated between methanol synthesis bioenergy with carbon capture and utilization and combined underground storage depending on the hourly electricity price and grid carbon intensity. The results indicate that the strategy has potential to maintain the average fuel carbon intensity within the 65% GHG reduction threshold set by the renewable energy directive III at a minimum methanol price of 870 EUR/t. This approach could facilitate implementation as it does not require dedicated renewable power generation and hydrogen storage, potentially decreasing costs compared to semi-islands and off-grid PtX systems.

Energy and GHG emissions assessment for biochar-enhanced advanced biofuels value chains

Biochar has an enormous potential to store carbon in the long-term. Differently than BioEnergy Carbon Capture and Storage (BECCS) technologies, biochar incorporates biogenic carbon in a solid form that offers multiple benefits as carbon sink, soil improver or for advanced materials production. The present study proposes an innovative approach, where carbon sequestration through biochar is obtained through the integration of slow pyrolysis with fast pyrolysis in decentralised biorefining systems, and then converted producing drop-in fuels from pyrolysis oil hydrotreating or gasification and Fischer-Tropsch (FT) synthesis. The scope is either to achieve negative GHG emissions assigned to advanced biofuels, or to export the generated carbon credit for the carbon markets (i.e. outside the biofuels carbon intensity). The innovative concept entails process integration and optimisation for the different stages of biomass drying, conversion and upgrading into biofuels in a way to reduce fossil-based inputs, applying a full value chain approach. Methodological choices for the assumptions on life cycle emissions calculation are discussed, evaluating the environmental performances by comparing the new concept to traditional biofuels value chains. Using a tailored lifecycle accounting methodology, this paper demonstrates that high GHG emissions savings can be achieved. The improved scenario shows how the carbon sequestration with biochar further reduces the carbon intensity up to –4.2 gCO2e MJ−1 for pyrolysis oil-based fuels, and to −20.2 gCO2e MJ−1 for FT-based fuels: this demonstrated that carbon negative sustainable biofuels can be obtained. The study demonstrates that an integrated biorefinery of 100 MW capacity can deliver additional 13.3 and 6.8 ktons of CO2e of GHG savings of per year, from drop-in fuels made of hydrotreated pyrolysis oil and FT synthesis, respectively.

Is it possible for semiconductor companies to reduce carbon emissions through digital transformation? Evidence from China

The semiconductor industry serves as both a driver of digital transformation (DT) and a bearer of energy preservation and lower emissions. This study focuses on the Chinese-listed semiconductor businesses from 2013 to 2021, delving into the mechanism of digital transformation on reducing carbon emissions. It validates the moderating function of supply chain configuration and reveals heterogeneity at both the regional and corporate levels. The following important results are reached by this work: Among semiconductor enterprises, firstly, digital transformation considerably reduces enterprises' carbon emission intensity, a conclusion that stands robust after robustness checks. Secondly, digital transformation achieves carbon mitigation by improving both green and traditional innovation efficiency. Thirdly, the increased centralization of supply chain configuration propels enterprises to achieve carbon reductions through digital transformation. Lastly, heterogeneity research finds that digital transformation in the eastern area inhibits the increase in carbon intensity, while the central-western and northeastern regions do not exhibit a similar trend. At the enterprise level, the carbon mitigation effect of digital transformation is especially noticeable in semiconductor enterprises that are highly labor-intensive, large in size, have high environmental uncertainty, and are state-owned. These findings provide empirical evidence for semiconductor enterprises to implement differentiated digital transformation practices and coordinate the creation of green transformation policies.

Effectiveness of carbon dioxide emission target is linked to country ambition and education level

In response to the Paris Agreement, a growing number of countries, 123 in total, have committed to carbon reduction targets. While existing research has assessed various policies’ effectiveness in achieving these targets, the potential of the act of goal-setting itself as a policy instrument has been underexplored. Here we leveraged a comprehensive panel dataset spanning 163 countries from 2011 to 2022 and employed a rigorous difference-in-difference model. Empirical findings reveal that both proposing carbon reduction targets and setting higher targets effectively reduce emissions intensity. The mechanism driving the impact of carbon reduction targets on CO2 emissions centers on the level of education, rather than renewable energy capacity, requiring further investigation to the mechanism. Subsequent analysis establishes connections between target levels and renewable energy capacity. Our results advocate for dynamic updates of carbon reduction targets aligned with renewable energy capacity when formulating climate objectives.

Trade flows, carbon leakage, and the EU Emissions Trading System

The EU Emission Trading System (EU ETS) has been shown to have reduced emissions in the participating countries and industries since its adoption in 2005. However, there is less evidence on the shifting of production outside EU to avoid emission controls. We study this so-called carbon leakage with gravity analysis of international trade flows and carbon intensities of trade. We utilize the gravity model on a sectoral level and study its implications empirically. Our findings with new OECD data indicate that some carbon leakage has in fact occurred due to the EU ETS, resulting in higher carbon content of imports to the EU. At the same time, we show that the EU ETS has induced lower carbon content of exports from the EU. In further analysis, we show that the carbon leakage we find has caused a moderate increase in total carbon content embodied in the EU’s trade, despite the decreases in exported carbon.

The impact of green finance on renewable energy development efficiency in the context of energy security: Evidence from China

The influence of green finance (GF) on renewable energy development efficiency (REDE) has garnered considerable attention from both academia and society. To study the changes in China's REDE in recent years and GF's effect on it, this research first evaluates 30 provinces’ REDE from 2010 to 2019 using a non-radial directional distance function (NDDF) based on global technical assumptions. Second, we evaluate the direct impact of GF on REDE. Finally, we explore the internal mechanism for how GF influences REDE. The results of this study are as follows. (1) GF has a significant promoting effect on REDE. (2) The improvement of renewable energy (RE) technological innovation level and the increase of foreign investment strengthen GE's promoting effect on REDE. (3) The positive effect of GF on REDE is prominent in regions with lower environmental regulations and carbon intensities and higher financial development levels. This paper offers relevant policy suggestions to improve REDE and to enhance GF development.

Carbon neutrality in Malaysia and Kuala Lumpur: insights from stakeholder-driven integrated assessment modeling

Introduction: Several cities in Malaysia have established plans to reduce their CO2 emissions, in addition to Malaysia submitting a Nationally Determined Contribution to reduce its carbon intensity (against GDP) by 45% in 2030 compared to 2005. Meeting these emissions reduction goals will require a joint effort between governments, industries, and corporations at different scales and across sectors.Methods: In collaboration with national and sub-national stakeholders, we developed and used a global integrated assessment model to explore emissions mitigation pathways in Malaysia and Kuala Lumpur. Guided by current climate action plans, we created a suite of scenarios to reflect uncertainties in policy ambition, level of adoption, and implementation for reaching carbon neutrality. Through iterative engagement with all parties, we refined the scenarios and focus of the analysis to best meet the stakeholders’ needs.Results: We found that Malaysia can reduce its carbon intensity and reach carbon neutrality by 2050, and that action in Kuala Lumpur can play a significant role. Decarbonization of the power sector paired with extensive electrification, energy efficiency improvements in buildings, transportation, and industry, and the use of advanced technologies such as hydrogen and carbon capture and storage will be major drivers to mitigate emissions, with carbon dioxide removal strategies being key to eliminate residual emissions.Discussion: Our results suggest a hopeful future for Malaysia’s ability to meet its climate goals, recognizing that there may be technological, social, and financial challenges along the way. This study highlights the participatory process in which stakeholders contributed to the development of the model and guided the analysis, as well as insights into Malaysia’s decarbonization potential and the role of multilevel governance.

Identifying drivers of county-level industrial carbon intensity by a generic machine learning framework

Carbon intensity has been recognized as a measure of the relative change between carbon emissions and economic development in numerous policy documents at multiple levels. Counties as the basic governmental units for policy formulation and implementation remain largely unexplored in climate governance. This study makes an effort to fill in this gap by examining the dynamics and drivers of industrial carbon intensity (ICI) at the county level. Given the data limitations at both county and industrial levels, we develop a data-driven method that evaluates six commonly used machine learning algorithms to study county-level ICI accounted by statistical data. We find that energy consumption and labor scale are two consistent and significant drivers of ICI across all results, especially, energy consumption acts as the crucial driver. Accordingly, we divide the overall industrial sector into small and large sub-sectors to provide differentiated policy implications. Small sub-sectors with low energy and labor inputs prioritize production-driven ICI reduction strategies, because increasing energy consumption by introducing automated machinery leads to rapid economic growth and thereby negatively impacts ICI. For large sub-sectors with high energy and labor inputs, efficiency promotion through technological innovation is required for ICI reduction. As an example of scenario analysis, we show that an integrated intensity reduction scenario by reducing energy consumption and short-term increasing labor scale and industrial scale will make it possible for Manufacture of Furniture sub-sector in the studied county to achieve an ICI reduction of 68.7% by 2060 compared to the 2015 level. Overall, this study provides an integrated and generic framework for predicting ICI at the county level to overcome the context of data scarcity, laying a basis for making differentiated and applicable policies for ICI reduction at the sub-city level.

A study of the relevance of seismic steel structures to urban carbon neutrality

Global warming has triggered dramatic climate change and natural disasters. Since the 21st century, the frequency of all kinds of extreme weather has increased significantly. This study, in accordance with the carbon peak targets and stage requirements, improve the building low carbon building standards system, accelerate the formulation, revision and collation of energy-saving design standards for public buildings energy-saving and carbon reduction standards. The application of earthquake-resistant steel structure of the building, the promotion of green low carbon building materials and green construction methods. Actively promote such buildings, the past sixty years each country's carbon emissions intensity have shown a general downward trend, especially South Korea, South Africa and Brazil and other countries due to economic development began to focus attention on environmental issues. In this study, we take Busan, Korea as an example, and use carbon neutral calculations to realize carbon neutrality by designing superstructures with a reduced degree of intensity, so that the reduction of carbon emissions mainly includes emission reductions brought about by a reduction in the amount of steel and cement used. It is hoped that this study will be taken into account, and that the early realization of peak carbon emissions in South Korea will be the current situation to be realized, and will be a challenge not only for developing countries, but also an important issue to be considered by all countries.

The interactive impact of green finance, ESG performance, and carbon neutrality

China's progress towards carbon neutrality is closely linked to ESG (Environmental, Social, and Governance) principles and the advancement of green finance. However, the underlying mechanisms that drive this integration have not been fully explored. In an era marked by the urgent fight against climate change, understanding these mechanisms is crucial for creating a sustainable economic paradigm that aligns developmental goals with environmental commitments. This study uses data from 30 provinces in China from 2011 to 2020 to construct a two-way fixed effects panel regression model that examines the relationship between ESG performance and carbon neutrality, while also addressing concerns about endogeneity. By incorporating a moderation effect model, the study explores the influence of green finance on this interconnectedness. Additionally, it employs grouped regression models to analyze the differing impacts across regions and industries, and conducts robustness checks across different time frames. The findings highlight the significant inhibitory impact of ESG performance on carbon emission intensity, which is further mitigated by the substantial moderating effect of advancing green finance. Further analysis of heterogeneity reveals that the central and western regions, as well as less industrialized provinces, exhibit a stronger suppressive effect of ESG performance on carbon intensity, which is additionally moderated by the presence of green finance. This study provides new insights into the dynamic relationships between green finance, ESG performance, and carbon neutrality, offering strategic implications for corporations, policymakers, and investors.

Enhancement of Maritime Sector Decarbonization through the Integration of Fishing Vessels into IMO Energy Efficiency Measures

The escalating impact of anthropogenic activities on global climate patterns necessitates urgent measures to reduce emissions, with the maritime industry playing a pivotal role. This article aims to examine the adoption of International Maritime Organization energy efficiency measures for the often-overlooked fishing vessels and their contribution to the overall maritime decarbonization efforts. The article analyzes the attained technical efficiency indices of a case study large-scale fishing vessel and compares them with those of two cargo ships where IMO measures already apply. To support the proposal, a comprehensive analysis of the energy efficiency indices of eight large purse seine fishing vessels is also presented. The results show that large-scale fishing vessels of 400 GT and above could be subject to the IMO energy efficiency measures. The operational challenges, unique to the fishing sector, suggest that sector-specific considerations may be required to integrate the fishing fleet into the already existing IMO energy efficiency guidelines. Looking ahead, this article explores the benefits of aligning Regulation (EU) 2023/957 and IMO guidelines, as well as applying the IMO Carbon Intensity Indicator (CII) in assessing the operational environmental impact of fishing operations, emphasizing the importance of including these vessels in the current regulatory frameworks to promote decarbonization.

Analysis of Factors Influencing the Spatial and Temporal Variability of Carbon Intensity in Western China

Analysis of Factors Influencing the Spatial and Temporal Variability of Carbon Intensity in Western China

Exploring the Impact of the Digital Economy on China's Export Implied Carbon Intensity: A Provincial Panel Data Analysis

Exploiting the positive effect of digital economy on reducing the implied carbon intensity of exports is an important path to promote the green and low-carbon transformation of China's export trade. In view of this, using the Chinese provincial panel data from 2008 to 2020 to scrutinize the consequential impact and intricate mechanisms at play between these variables. Employing a robust methodology, including fixed-effects models, mediating-effects models, and threshold models, the analysis delves into the multi-faceted impact of the digital economy on export implied carbon intensity. It is found that (1) The enhancement of the digital economy can significantly reduce the implied carbon intensity of exports. (2) The digital economy further diminishes the implied carbon intensity of exports through the mediating influences of industrial structure and technological progress. (3) The relationship between the digital economy, industrial structure, and technological progress exhibits a noteworthy non-linear dynamic concerning export implied carbon intensity.

Shared pooled mobility essential complement to decarbonize China’s transport sector until 2060

Greenhouse gas emission reduction in the passenger transport sector is a main challenge for China’s climate mitigation agenda. Electrification and shared mobility provide encouraging options for carbon emissions reduction in road transport. Based on an integrated scenario-based assessment framework, a provincial-level projection is made for vehicle growth and CO2 emissions in China under shared socioeconomic pathways (SSPs). This work illustrates how passenger car electrification and sharing contribute to China’s “30·60” climate goals (peaking of CO2 emissions by 2030 and carbon neutrality by 2060). The results demonstrate that China is en route to achieving the goal of a 2030 carbon peak (1.0Gt CO2) under current conditions, and could reach peak emissions around 2026 with optimistic growth in EVs and shared mobility. Compared with no policy action, the single EV policy (shifting from ICEVs to EVs) can reduce 71% of emissions by 2060, thus narrowing but not closing the mitigation gap to carbon neutrality in passenger cars (302 Mt CO2). Shared mobility can provide further emission reduction support, reducing emissions by 83% in 2060. Comprehensive climate actions (including electrification, sharing mobility to reduce car use, and improving vehicle efficiency and fuel carbon intensity) are needed to achieve deep decarbonization to net-zero by 2060 in the passenger transport sector.

Towards zero-carbon cities: how does environmental information disclosure impact the risk of carbon locking?

Utilizing panel data from 119 cities spanning from 2013 to 2019, the study rigorously investigates the influence of environmental information disclosure (EID) on mitigating the risk of urban carbon lock-in through the application of both two-way fixed effects and spatial econometric models. The findings robustly indicate that EID plays a significant role in facilitating carbon unlocking within cities, a conclusion that remains steadfast even after addressing potential endogeneity issues. Mechanistically, it is revealed that EID can effectively decrease the risk of carbon lock-in by enhancing urbanization levels and reducing energy intensity. Furthermore, the study unveils that the efficacy of EID in curbing urban carbon lock-in risk is also contingent upon factors such as carbon intensity, population size, and environmental quality, highlighting the multifaceted nature of EID's impact on urban carbon management. Specifically, the increase in carbon intensity, the expansion of population size, and the deterioration of environmental quality will reduce the carbon unlocking effect, which may not be conducive to the achievement of the goal of "carbon neutrality" in cities. The spatial effect test found that EID and carbon locking risk are both spatially significant positive autocorrelation, the deepening of local EID can significantly cut the risk of carbon locking in neighboring cities, and the urbanization pathway and energy saving pathway exist both locally and in neighboring places.

Effect of waste clay brick powder on microstructure and properties in blended oil well cement pastes at HTHP conditions

The use of waste materials to improve the thermal stability of oil well cement (OWC) at high temperature and high pressure (HTHP) conditions has received increasing attention. This study investigated the performance of sustainable blended OWC pastes by recycling waste clay brick powder (CBP) as a partial substitute for commercial high temperature resistant additives (silica flour, SF). The main objective was to assess the impact of these substitutions on the hydration, microstructure and mechanical properties of blended OWC. CBP was incorporated at substitution rates of 25 wt%, 50 wt%, 75 wt% and 100 wt% by weight of SF. These pastes were firstly precured at 50 °C for 7 days (to simulate the primary cementing operation prior to steam injection), and then thermally cycling cured at 300 °C/13.0 MPa (to simulate the steam injection process). The study conducted comprehensive tests and analyses, including compressive strength, gas permeability, hydration products and microstructural analyses. The results showed that the suitable substitution rate of CBP in this study was 25 wt%-50 wt%. At these substitution levels, the blended OWC pastes had good compressive strength (18.5 MPa and 17.9 MPa) and low gas permeability (3.1 × 10−3 mD and 4.51 × 10−3 mD). From the environmental and economic analyses, the energy intensity and CO2 emissions of all blended OWCs were significantly lower compared to those of conventional OWC. Meanwhile, the cost of blended OWC in this study was significantly lower compared to that of the commercial SF-OWC system. Overall, this study highlighted the potential of recycling waste materials to promote raw material sustainability and improve the performance of OWC pastes at HTHP conditions.

A global dataset of carbon pumping by the world’s largest tropical rivers

The eco-morphodynamic activity of large tropical rivers interacts with riparian vegetation causing implications for the carbon cycle within inland waters. Through a multi-temporal analysis of satellite data spanning the years 2000–2019, we analyzed rivers exceeding 200 m in width across the tropical regions, revealing a Carbon Pump mechanism driving an annual mobilization of 12.45 million tons of organic carbon. The study identifies fluvial eco-morphological signatures as proxies for carbon mobilization, emphasizing the link between river migration and carbon dynamics. To enhance accessibility, our results are encapsulated in a visually compelling WebGIS application, offering a comprehensive understanding of the eco-geomorphological influences on the global carbon cycle within large tropical rivers. Our findings are instrumental in determining the carbon intensity of future hydropower dams, thereby contributing to informed decision-making in the realm of sustainable energy infrastructure. This study elucidates the intricate relationships that govern the nexus of tropical river dynamics, riparian ecosystems, and the global carbon cycle.