Carbon Footprint Evaluation Research Articles

Carbon footprint evaluation for electric vehicles considering green electricity trading

Electric vehicles (EVs) are often seen as a symbol of environmental friendliness. However, while EVs themselves do not directly emit carbon, the electricity they rely on may still contribute to carbon emissions. It is challenging to accurately assess the environmental impact of different types of electric energy used in charging stations due to unified pricing transactions. This hinders the precise measurement of each EVs' carbon footprint. To address this issue, this paper proposes a method for evaluating the carbon footprint based on Carbon Emission Flow (CEF) and energy traceability. A carbon integral mechanism is designed based on the China Certified Emission Reduction (CCER) scheme for coupling EVs with green electricity trading. These elements are integrated into the EV carbon footprint evaluation. Furthermore, the EVs' carbon footprint is minimized to select the lowest-carbon charging path for EVs owners. The feasibility of this proposed method is verified using an example from IEEE33 which quantifies EV footprints and indirect carbon emissions within the distribution network, ultimately encouraging consumption of green electricity by EVs and promoting more environmentally friendly modes of travel.

Integrated nutrient management on oat + grasspea intercropping system: an evaluation of system productivity, economics, energetics and carbon footprint

A field investigation took place at Central Research Farm of Bidhan Chandra Krishi Viswavidyalaya, West Bengal, India during winter seasons of 2020–21 and 2021–22 with the aim to evaluate system productivity, economics, energetics and carbon footprint (CF) of oat + grasspea intercropping systems under different integrated nutrient managements (INM). The experiment was executed in split-plot design with 4 cropping systems in main plots and 4 levels of nutrient management in sub plots. The 3:3 intercropping system of oat + grasspea ensured highest system productivity, whereas sole grasspea stood best in terms of economics, energetics and environment safety by lowering CF. Notably, INM involving 75% N through urea + 25% N through vermicompost registered significantly higher system productivity in case of 3:3 oat + grasspea intercropping system (CS4N3) (18.77 q ha−1). Further, this intercropping system yielded high economic profitability (net return: US$ 430.4 ha−1, benefit–cost ratio: 1.71) as well as energy indices (energy output: 71179.1 MJ ha-1, net energy gain: 60352.0 MJ ha−1, energy ratio: 6.57 and energy profitability: 5.57). CF was also found relatively low under CS4N3 (Yield scaled CF: 62.2 kg CO2-e q−1). Furthermore, high carbon efficiency (7.92) and carbon sustainability index (6.92) were also exhibited by CS4N3 as it produced maximum carbon output (1801.2 kg ha−1). In conclusion, the 3:3 oat + grasspea intercropping system using INM can be viable option to ensure economic and energy viability and minimize greenhouse gas emissions without compromising system productivity. Particularly, this intercropping system combined with 75% N through urea + 25% N through vermicompost as INM option can be recommended for the cereal and legume growers of India, specifically under intensive cropping scenario.

Investigation on Surface Roughness and Power Consumption for Sustainability Assessment in Hard Turning of HSLA Steel With SPPP‐AlTiSiN–Coated Carbide Tool Under Various Cooling‐Lubrications

ABSTRACTThe present research analyses the power consumption (Pc) and surface roughness (Ra) in hard turning of high‐strength low‐alloy (HSLA) grade AISI 4140 steel using a recently developed AlTiSiN‐coated carbide tool under different cooling‐lubrication conditions (dry, flooded, nanofluid‐MQL). The nanofluid was prepared by mixing the MWCNT nanoparticles with an eco‐friendly automotive radiator coolant (base fluid). The cooling‐lubrication performance is investigated briefly by comparing the machining responses like machined surface morphology, tool wear, cutting force and temperature. The experiments associated with 46 trials were performed by considering various machining variables, namely cutting speed, nose radius, depth of cut, feed and cooling‐lubrication methods. From the perspective of predictive modelling and multi‐response optimisation, response surface methodology has been employed to minimise power consumption and surface roughness. Thereafter, the predictive modelling and optimisation results are implemented for economic analysis and energy‐saving carbon footprint evaluation. This innovative research also addresses comparative environmental sustainability evaluation in hard turning under different cooling‐lubrication conditions using a life cycle assessment methodology for cleaner and safer production. Results indicate that cutting speed was the most influential item in power consumption enhancement. Furthermore, compared with dry and flooded turning, lower cutting force, reduced cutting temperature, shorter width of flank wear and better surface morphology were obtained under nanofluid‐MQL machining. It has been observed that nanofluid‐MQL machining outperformed sustainability improvement concerning techno‐economically viable societal acceptable and environmental friendliness.

Improving rapeseed carbon footprint evaluation via the integration of remote sensing technology into an LCA approach

Agricultural carbon footprint (CF) evaluation plays an important role in climate change mitigation and national food security. Many studies have been conducted worldwide to evaluate the CF of rapeseed and its byproducts; however, only a few of these studies have considered finer-scale spatial-temporal heterogeneity. Considering the advantages of using detailed crop information extracted by remote sensing (RS) techniques, we attempted to integrate RS into life cycle assessments to improve rapeseed CF evaluation. A case study was conducted from 2021 to 2023 in one of the most important grain- and rapeseed-producing areas in Southwest China, namely, the Chengdu Plain, covering an area of 18,810.00 km2. The results of our study suggest that: (1) the proposed approach is applicable for high-resolution (10 m ∗ 10 m) rapeseed distribution mapping; (2) the farm-based CFs of rapeseed in the studied region range from 3333.08 to 4572.82 kgCO2-eq ha−1, while the product-based CFs (PCFs) vary from 1316.23 to 2443.95 kgCO2-eq t−1. Nitrogen fertilizer processing and its application are identified as the dominant contributors to upstream and downstream greenhouse emissions (GHGs), respectively; (3) the significant role of soil properties and soil organic carbon in influencing crop PCFs indicates good GHG offsets. The method used in the current study has strong adaptability and universality in different areas with various climatic conditions and can provide a solid basis for policymakers to formulate differentiated agricultural carbon reduction policies.

Evaluation of carbon footprint due to household electricity consumption in Iranian provinces

Evaluation of carbon footprint due to household electricity consumption in Iranian provinces

A simplified machine learning product carbon footprint evaluation tool

On the way to climate neutrality manufacturing companies need to assess the Carbon dioxide (CO2) emissions of their products as a basis for emission reduction measures. The evaluate this so-called Product Carbon Footprint (PCF) life cycle analysis as a comprehensive method is applicable, but means great effort and requires interdisciplinary knowledge. Nevertheless, assumptions must still be made to assess the entire supply chain. To lower these burdens and provide a digital tool to estimate the PCF with less input parameter and data, we make use of machine learning techniques and develop an editorial framework called MINDFUL. This contribution shows its realization by providing the software architecture, underlying CO2 factors, calculations and Machine Learning approach as well as the principles of its user experience. Our tool is validated within an industrial case study.

Application and carbon footprint evaluation of lignin-based composite materials

Application and carbon footprint evaluation of lignin-based composite materials

Evaluation of carbon footprint of compression cast waste rubber concrete based on LCA approach

Compression cast waste rubber concrete (CCWRC) is a type of concrete that using waste tire rubber to replace conventional coarse aggregates and adopting the compression cast process to improve the mechanical properties of concrete. This type of concrete has the potential for carbon reduction, however, there is a lack of quantitative research to evaluate the carbon footprint (CFP) of CCWRC. By adopting the life cycle assessment (LCA) method, the CFP and carbon reduction potential of CCWRC are assessed in this study. The results show that the CFP of CCWRC with conventional coarse aggregates decreases by 37%–50% compared to conventional concrete; and decreases by 28%–46% compared to uncompressed rubber concrete. When using conventional recycled aggregate, acetic acid-treated recycled aggregate, and lime-carbonated recycled aggregate as substitutes, and adding 10% rubber in CCWRC, the CFP of CCWRC can be reduced by 28%–34%, and 29%–32% compared to conventional concrete and uncompressed rubber concrete, respectively. The research results can provide theoretical and data basis for the evaluation of CFP of concrete production and promote the application of CCWRC and cleaner production in construction industry.

Carbon Footprint Evaluation in Tunnels Excavated in Rock Using Tunnel Boring Machine (TBM)

The generation of CO2 is an important element in assessing the environmental impact generated in a tunnel construction project, making this knowledge very useful for evaluating different alternatives. In this study, an analysis of the carbon footprint has been carried out, including the main elements during the construction phase of a tunnel employing a tunnel boring machine (TBM). The research proposes several options for an easy and quick calculation of CO2 generation in a design phase. Its determination can be crucial for decision-making before and during the execution of any tunnel in the near future. The estimation models have been validated based on real case studies, defining the carbon footprint of each construction element. The proposed procedure can apply to any tunnel. However, it should be noted that it is an approximate analysis, and the limitations described in each section should be considered. The main CO2 generator found in the construction process is the lining element; the percentage varies between 50% in tunnels with smaller diameters (4–5 m) and 75% for tunnels with larger diameters (9–10 m), followed by the auxiliary elements, 16%, and the operation of the tunnel boring machine itself, 11.2%, while the other parts remain in a range between 1.3 and 5.7%. This knowledge makes it possible to define the aspects on which efforts should be focussed to reduce the carbon footprint of the tunnel construction process.

Regional spatial econometric Analysis of carbon footprint of energy consumption based on clustering algorithm

Abstract The structure of energy consumption and reducing the carbon footprint has become an important issue in the field of carbon and energy conservation. This paper adopts spatial econometric Analysis to construct a framework for analyzing the influencing factors of carbon emissions based on the STIRPAT model. It applies the K-means algorithm to effectively cluster and classify the energy consumption of different regions. Then, the article analyzed these clustering results in depth using the Kaya constant equation to calculate the carbon emissions of each area. The results of the carbon footprint analysis reveal that the Gini coefficient of carbon emissions in the eastern region peaked at 0.352 in 2014, while decreasing to a low of 0.284 in 2019. the western and central areas have the highest Gini coefficients of carbon emissions at 0.271 and 0.248, respectively. furthermore, from 2015 to 2022, the ecological pressure on the carbon footprint of the whole industry has always remained at 3.033 above, reaching a historical high of 3.433 in 2022.The application of this paper not only helps to solve the problems in the existing carbon footprint evaluation methods, but also provides a scientific basis for more effective management and reduction of carbon emission.

ANALYSIS ON POWER CONSUMPTION FOR LIFE CYCLE SUSTAINABILITY ASSESSMENT IN HARD TURNING OF AISI 4140 STEEL USING SPPP—AlTiSiN-COATED CARBIDE TOOL UNDER VARIOUS CUTTING ENVIRONMENTS

High strength low alloy (HSLA) AISI grade 4140 is grabbing the eyes of automobile industries for its superior properties. However, the production of finished components of HSLA steel by machining under dry environment is challenging owing to high cutting temperature and friction. The usage of low-cost coated carbide tools and environment-friendly cooling-lubrication approach are thereof being given importance for the past few decades for economic and sustainable machining. In this study, the power consumption (Pc) during the hard turning process of AISI 4140 steel was analyzed using an AlTiSiN-coated carbide tool under various cutting environment conditions, including dry cutting, flooded cutting, and nanofluid-MQL cutting. For this study, the nanofluid was prepared by blending MWCNT nanoparticles with an environmentally friendly automotive radiator coolant, which served as the base fluid. Briefly, the cooling-lubrication performance is investigated by comparing the machining responses like machined surface morphology, tool wear, cutting force, and temperature. The variance analysis was adopted to determine the significance level of experimental parameters (speed, feed, nose radius, depth of cut, cutting environments) affecting the Pc. To predict and optimize Pc during hard turning with machining variables, the response surface method (RSM) was proposed. Following the predictive modeling and optimization, the results were applied for economic assessment and for energy saving carbon footprint evaluation. This innovative research also addresses comparative sustainability evaluation in hard turning under different C/L environments using life cycle assessment (LCA) towards cleaner and safer production. Results indicate that cutting speed was the most influential item on Pc enhancement. Furthermore, as compared to dry and flooded turning, lower cutting force, reduced cutting temperature, shorter width of flank wear, and better surface morphology are obtained under nanofluid-MQL machining. It is experienced that nanofluid-MQL machining outperformed towards sustainability improvement concerning techno-economically viable societal acceptable and environment friendliness.

Importance of process design on carbon footprint from drinking water treatment by enhanced coagulation-filtration

Abstract There are several process design options for enhanced coagulation-filtration in drinking water treatment plants (DWTPs). This study compares the carbon footprint and economic impact of two common process designs based on enhanced coagulation-filtration with pH, Ca, and alkalinity adjustment for corrosion control. The process designs are direct filtration (DF) using Al coagulant with limewater (DF-Al) and contact filtration (CF) using Fe coagulant with alkaline filter layers (CF-Fe). The operational data are retrieved from full-scale DWTPs. The results show that the carbon footprint from operations is five times larger for the DF-Al compared to the CF-Fe. Operational costs covering chemicals and energy are almost 30% higher for the DF-Al. Simplified material intensity estimations for the construction phase show that the carbon footprint and investment cost increase with increasing process area, which are larger for the DF-Al. Therefore, to reduce environmental impacts and costs, the design of drinking water treatment processes should be carefully considered even for very similar processes. The results should motivate both water professionals and decision-makers to include a carbon footprint evaluation as a routine step in the DWTP selection and design phases.

Carbon footprint evaluation of routine anatomic pathology practices using eco-audit: Current status and mitigation strategies

Because of global warming, integrating an ecological dimension to the practice of pathology is crucial, as already performed in other medical specialties. The aim of the study was to estimate the greenhouse gas emissions (GHE) of one biopsy/surgical specimen hematoxylin-phloxine-saffron (HPS) slide, one frozen section examination, and one immunohistochemistry (IHC) slide, and to propose environmentally friendly recommendations.The different steps of the pathological procedures, from sample transport to slide/block destruction, were considered for the GHE evaluation. Consumables and reagents used at each step were noted, as well as the electricity consumption of the premises/equipment, specific wastes, and staff travel. The GHE analyses were performed according to the eco-audit method.The GHE attributable to one HPS slide of a biopsy, one HPS slide of a surgical specimen, one frozen section examination, and one IHC slide were 0.589 kgCO2e (CO2 equivalent), 0.618 kgCO2e, 1.481 kgCO2e, and 0.363 kgCO2e, respectively. For a one-year activity in the pathology department, the GHE for HPS was estimated at 91,897 kgCO2e, equivalent to 422,321 km of thermal car ride. The main GHE sources were staff travel for one biopsy HPS slide (34.2 %) and one surgical specimen HPS slide (32.6 %), materials (39.1 %) and staff travel (27.2 %) for one frozen section examination, and staff travel (28.2 %) and reagents and their packaging (44.9 %) for one IHC slide.The present study highlighted the most significant sources of GHE for routine practices in a pathology department, underlining that, from pathologists to policy makers, each actor has a responsibility to implement sustainable changes.

Methodological introduction to the carbon footprint evaluation of intermodal transport

Managing logistics processes from an environmental perspective is increasingly important in international supply chains. Essential elements of global logistics are supply chains based on intermodal logistic units. The specificity of this type of shipment, which often involves several modes of transport, requires a precise definition of model boundaries and identification of specific factors determining the level of carbon footprint. This research is focused on identifying the specific emissivity level of each intermodal transport stage. The conducted study refers to the international emission evaluation guidelines gathered in the UN GHG Protocol. The carbon footprint (CF) evaluation commenced during the case study indicated the need to consider the specificity of the assigned modes of transport. Hence selected emission factors such as US DEFRA, US EPA, KOBiZE and UNFCCC were engaged for better carbon footprint evaluation related to each stage of the intermodal transport process. In the summary part, the environmental efficiency level of each mode of transport has been compared. The sea freight mode was indicated as the most efficient in terms of overall kg*eCO2 per kilometre. The study shows that intermodal maritime transport, taking into account the weight of the goods transported and the distance, is approximately 68% more efficient than road transport. However, it must be mentioned that to identify the differences comprehensively, transshipment operations must also be taken into account in each scenario. Further research steps and recommendations have been presented in the last section of this research.

Discussion on key issues of carbon footprint accounting for bast fiber textiles

Bast fiber textiles have become increasingly popular as a sustainable alternative in recent years. Although the carbon emissions of bast fiber textiles have been studied using life cycle assessment method, there is a lack of comprehensive literature analyzing and summarizing the results. This study reviews the current state of research on the carbon emissions of bast fiber textiles. Compared to other plant fibers, there are fewer studies on the carbon footprint or life cycle assessment of bast fiber textiles, and these studies lack a comprehensive “cradle to grave” or “gate to grave” analysis. In addition, inconsistencies exist in the allocation methods used for carbon footprint assessments. This study suggests a combination of physical and economic allocation to conduct a more accurate environmental impact assessment of bast fiber textiles. On the basis of the above review, this study modularizes the process of the entire life cycle of textiles and analyzes the carbon sequestration and emission characteristics to determine the main considerations for carbon footprint assessment. The carbon sequestration effect of bast fiber textiles should be analyzed at the raw material extraction stage and at the end-of-life stage. Oxygen release and consumption are also considered as additional factors to be quantified and analyzed in this study. In the future, the modular method should be used for all carbon footprint evaluation reports for bast fiber textiles. This method helps to comprehensively quantify and evaluate the carbon footprint of bast fiber textiles throughout their entire life cycle. It can provide recommendations for green design, green production and sustainable consumption.

Achieving significant carbon emission reduction by chemical conversion of calcium carbide furnace gas reforming to higher alcohols

China is the world's largest producer and consumer of calcium carbide, but the inefficient and uneconomical utilization of carbide furnace gas (CFG), which is rich in CO and H2, hinders the development of the calcium carbide industry. This study aims to solve this issue by using CFG through chemical conversion to synthesize clean fuel higher alcohols (HAS). The carbon emission reduction effect of the synthesis process was thoroughly analyzed using the atom economy evaluation, energy analysis, carbon metabolism evaluation, and carbon footprint evaluation methods. In this work, the HAS synthesis process ultimately released only 1.89% of the carbon in CFG as CO2. Compared with the direct emission of CFG without utilization, the direct carbon footprint of greenhouse gas emissions after HAS synthesis decreased by 87.68%. The chemical conversion of CFG into HAS is beneficial to carbon emission reduction and clean fuel production in the calcium carbide industry.

Fabrication of a bamboo-based glulam based on reconstitution unit innovation: Mechanical property investigation and carbon footprint evaluation

The development of high-quality, large format bamboo structural materials is a hot spot. Here, we fabricated a flattened bamboo board (FB) with a large size, which was further laminated and lengthened to prepare FB-based glulam. Two kinds of FBs were fabricated based on different flattening methods: notched-FB and smooth-FB. Compared with the notched-FBs, the modulus of rupture (MOR) and modulus of elastic (MOE) values of smooth-FBs which were previously softened at 175 °C increased by 9.2% and 7.7%, respectively. The FB-based laminated boards whose middle bonding layer is yellow surface to yellow surface show the best mechanical properties among all the three candidates, with dry shear strength, compressive strength parallel to grain, tensile strength parallel to grain, MOR and MOE values of 20.7 MPa, 52.5 MPa, 115.6 MPa, 119.6 MPa and 14.2 GPa, respectively. Finally, two lengthening methods of horizontal and vertical finger connections were introduced to enlarge the size. The results indicate that the FB-based glulam with extension interfaces near to the two terminal points of each laminated boards exhibits better bending resistance with a MOR value as large as 95.9 MPa, being attributed to the corresponding distributed stress and extended the stress transmission distance. The FB-based glulam is proved to be a carbon-neutral product with a carbon footprint value of − 1.12 kg CO2/t. This work is the first time to use FBs as reconstituted units for bamboo glulam. We hope to discuss the effects of changes in process parameters and methods at different manufacturing stages on the physical and mechanical properties of the material, thus providing an experimental and theoretical basis for the application of FBs in the field of large-scale bamboo-based structural materials and also broadening the application field of bamboo with high added value.

Study on the Effect of Flattening Modification on Bamboo Cutting Board and Corresponding Carbon Footprint Evaluation

Bamboo, as a renewable biomass material, has received wide public attention. However, due to the thin-walled and hollow structure of bamboo, the mainstream processing method is complex and requires splitting the bamboo into narrow strips and then gluing them together for further manufacturing products. In addition, the surface glue residue makes the safety of indoor applications a concern, especially for cutting boards that come into contact with food. In response to the above problems, this paper introduces a bamboo flattening technology, which can flatten and unfold the pre-treated bamboo into a large-size flattened bamboo board (FBB). The results show that, compared to untreated bamboo, the dimensional stability of the FBB was improved and the flexural strength and elastic modulus of the FBB were increased by about 8.0%. The flattened bamboo cutting board was manufactured with the FBB as the surface layer and had a moisture content and hardness value of 9.2% and 5080 N, respectively, and the accumulated dip peel length of any glue layer was less than 25 mm. The flattened bamboo cutting board is proved to be a carbon-neutral product with a carbon footprint value of −42.92 kg CO2/t. This work provides a theoretical basis for the fabrication of large-size unspliced bamboo boards and provides new ideas for the scenario-specific application of FBBs. Using a FBB to make cutting boards can avoid contact between food and adhesives, making them more hygienic. The findings of this research can be used to make bamboo cutting boards more hygienic, environmentally friendly and possess excellent physical and mechanical properties.

Carbon footprint assessment of face masks in the context of the COVID-19 pandemic: Based on different protective performance and applicable scenarios

Widespread concerns have been raised about the huge environmental burden caused by massive consumption of face masks in the context of the COVID-19 pandemic. However, most of the existing studies only focus on the environmental impact associated with the product itself regardless of the actual usage scenarios and protective performance of products, resulting in unrealistic conclusions and poor applicability. In this context, this study integrated the product performance into the existing carbon footprint assessment methodology, with focus on the current global concerns regarding climate change. Computational case studies were conducted for different mask products applicable to the scenarios of low-, medium- and high-risk levels. The results showed that reusable cotton masks and disposable medical masks suitable for low-risk settings have a total carbon footprint of 285.484 kgCO2-eq/FU and 128.926 kgCO2-eq/FU respectively, with a break-even point of environmental performance between them of 16.886, which implies that cotton masks will reverse the trend and become more environmentally friendly after 17 washes, emphasizing the importance of improving the washability of cotton masks. Additionally, the total carbon footprints of disposable surgical masks and KN95 respirators were 154.328 kg CO2-eq/FU and 641.249 kg CO2-eq/FU respectively, while disposable medical masks and disposable surgical masks were identified as alternatives with better environmental performance in terms of medium- and high-risk environments respectively. The whole-life-cycle oriented carbon footprint evaluation further indicated that the four masks have greater potential for carbon emission reduction in the raw material processing and production processes. The results obtained in this study can provide scientific guidance for manufacturers and consumers on the production and use of protective masks. Moreover, the proposed model can be applied to other personal protective equipment with similar properties, such as protective clothing, in the future.

Poly(vinyl acetate-co-crotonic acid) from bio-based crotonic acid: synthesis, characterization and carbon footprint evaluation

Poly(vinyl acetate-co-crotonic acid) is synthesised starting from crotonic acid obtained from sewage sludge through the integration of (thermo)chemical and biological approaches, resulting in the valorization of a waste into a resource in a circular economy perspective.