Activity-based allocation and optimization for carbon footprint and cost in product lifecycle

Product design stage has a profound impact on a product's carbon footprint in its life cycle. Existing low-carbon design approaches are either not able to achieve low-carbon design solutions in product life cycle or prone to a loss of optimal solutions with the consideration of product life cycle. At each stage of product life cycle, there are several alternative design solutions, which can provide extra design space and bring more opportunities for low-carbon design. In this paper, a feature-based carbon footprint element model is proposed to estimate the carbon footprint at each stage of product life cycle. A five-layer weighted directed graph-based life cycle decision space is also proposed to represent the alternative life cycle paths. The low-carbon design process is to search the design solution with the lowest carbon footprint based on the mapping between design solution space and life cycle decision space. The proposed design process is to provide an integrated approach to enumerate and combine alternative solutions at each stage of product life cycle. The low-carbon design of a cold heading machine is given as an example to demonstrate the design methodology.

Low-carbon design is a design process for a product with the consideration of greenhouse gas emissions during its entire life cycle, which has an essential effect on product carbon footprint. However, existing approaches for low-carbon product design are either inextensible to achieve low-carbon design solutions in product life cycle or prone to a loss of optimal solutions under the dual consideration of carbon footprint and cost in product life cycle. This paper is devoted to a systematic Lagrange Relaxation-based approach to cost-constrained low-carbon product design for product life cycle. After the calculation model of carbon footprint for product life cycle is proposed, network-based representation model for low-carbon product design under the consideration of carbon footprint and cost in product life cycle is proposed. A Lagrange Relaxation-based constrained shortest path algorithm is then applied to produce design solutions with the consideration of carbon footprint and cost in product life cycle. The cost-constrained low-carbon product design of cold heading machine tool is given as an example, which demonstrates that the methodology is helpful to produce valuable solutions with the dual consideration of product carbon footprint and cost in product life cycle.

To mitigate global warming, companies are being compelled to control greenhouse gas (GHG) emission in the supply chain. As a fundamental quantisation parameter of carbon emission in product life cycle (PLC), carbon footprint (CF) captures the interest of governments, firms and consumers. However, calculating CF is a prerequisite to confirm or refute best practices and policies for controlling CF. This research examines the method of calculating CF of tobacco industry based on PLC. For different stages of PLC, it presents different models to measure CF at four stages respectively, through which firms especially tobacco industry could find out where carbon emits too much and then could implement corresponding measures to control or even reduce CF. Customers could consider the low-carbon product through carbon labels. For government or related organisations, it could open a new way to promote efficient emission reduction policies, which can control GHG and mitigate global warming.

Purpose – The current study focuses on determining the carbon cost of a company which operates in iron and steel sector within the scope of cost accounting. As a result of approval of Kyoto Protocol by several countries, carbon focused inquires such as; carbon trade, carbon tax, investing in low carbon technologies, decreasing carbon emission and calculation of carbon cost have been essential issues that companies must concentrate on. Within this context, “Carbon Accounting” which is considered as a new concept has increasingly been significiant for the companies. Design/methodology/approach – In this study, case study method were used in a company which operates in iron and steel sector for carbon accounting. By means of this case study, first, company’s existing production and accounting systems were examined then carbon emissions, carbon footprint and share of carbon emissions in total production cost were calculated for 2016 and 2017 years. Findings – By means of this case study, emissions from the process and combustion were determined. Emissions from the process were examined by total value ,not detailed sub group, and emissions from combustion were composed of coal and natural gas. Mass balance method has been used by company to determine carbon foot print and it was determined that carbon footprint is 4,78 ton CO2 emission for year 2016 but 4,22 ton CO2 emission for year 2017. Beside, it was calculated that unit carbon cost is 128,04 TL/ton for year 2016 but 117,95 TL/ton for year 2017. Additionally, in this company emission cost were comprised of % 99 of total environmental cost for 2016 and 2017 years. However the percentage of carbon emission cost in unit production cost was approximately % 9 for year 2016 while this percentage was decreased to approximately % 8 for year 2017 in this company. Discussion – By this case study which was performed in a company operating in iron and steel sector it was explored that carbon foot print and unit carbon emission cost decreases and also the percentage of unit carbon cost in unit production cost decreases in 2016-2017. Beside, carbon cost constitute a significiant part of environmental cost. Therefore determining, recording, classificiation and reporting of carbon cost are crucial for companies. This study may be a referance for companies and another studies to determine carbon cost.

Key parts refer to the problematic parts which have higher carbon emissions and need to be further optimized in low-carbon design. However, it is difficult to pick them out for designers because the quantitative relationship and unified connection between product life cycle stages and carbon emissions are hard to determine. To efficiently and effectively select the key parts of equipment products, this paper presents a selection methodology based on the characteristic of carbon emissions for low-carbon design. First, a low-carbon design framework is constructed to guide the low-carbon design process. Second, an embodied carbon-energy field (ECEF)-based selection method is proposed to help product designers make a decision. The ECEF denotes the carbon emissions distribution on product structures. Based on the temperature field of products, the ECEF can be constructed by integrating the main life cycle stages of products. The definition of ECEF is given initially. Then, the mapping mechanism and process between the temperature field and ECEF are studied. Meanwhile, the mathematical model of the ECEF is also presented to support the mapping process. Thus, the total carbon emissions distribution of every part and every point can be achieved by the ECEF of products and also seen by product designers visually. Therefore, the key parts could be selected easily. Finally, the proposed method is applied to a CNC gantry type honing machine to validate its feasibility and correctness. The result shows the selection method can be used to identify the problematic parts and points effectively and easily.

World agriculture is facing a great joint challenge of ensuring food security and mitigating greenhouse gas emissions under climate change. Characterizing the carbon footprints of crop production by life cycle analysis is be critical for identifying the key measures to mitigate greenhouse gas emission while sustaining crop productivity in the near future. In this chapter, the carbon footprints of bulk crop production; individual staple crops of rice, wheat, and maize; as well as vegetable crops from China were analyzed using data from either statistical archive or of questionnaire survey for quantification of all carbon costs in a whole life cycle. Although the overall carbon footprint of crop production sector of China is much higher than that of the UK and USA, rice and wheat have significantly higher carbon footprints than maize. The nitrogen- fertilizer-induced footprint was shown to be the biggest contributor to the total carbon footprint for all the crops (more than 60 %), leaving a big space for mitigation of luxury emissions of N2O with nitrogen use in excess. Although the carbon footprint has quickly increased since 1970s, crop production did not show a positive response to increasing carbon cost. While reducing nitrogen chemical fertilizer use is apparently a key option to cut down the highly carbon- intensive agriculture, substitution of rice or wheat with maize would offer a final option to ensure both high cereal production and low carbon cost in China’s crop production sector. There is an urgent need to depict the variation of carbon footprints for different cropping and farming systems, climate conditions, and the threshold of nitrogen luxury emissions for a certain crop.

To mitigate global warming, companies are being compelled to control greenhouse gas (GHG) emission in the supply chain. As a fundamental quantisation parameter of carbon emission in product life cycle (PLC), carbon footprint (CF) captures the interest of governments, firms and consumers. However, calculating CF is a prerequisite to confirm or refute best practices and policies for controlling CF. This research examines the method of calculating CF of tobacco industry based on PLC. For different stages of PLC, it presents different models to measure CF at four stages respectively, through which firms especially tobacco industry could find out where carbon emits too much and then could implement corresponding measures to control or even reduce CF. Customers could consider the low-carbon product through carbon labels. For government or related organisations, it could open a new way to promote efficient emission reduction policies, which can control GHG and mitigate global warming.

Insights into carbon and nitrogen footprints of large-scale intensive pig production with different feedstuffs in China

Greenhouse gas emission has become a recent global concern for green manufacturing. As product low-carbon design is an essential approach to achieve low-carbon manufacturing, which has a profound effect on the product carbon footprint, many researches have been focused on it in recent years with a result of valuable contributions. This paper is devoted to presenting a dynamic programmingbased approach to product low-carbon design. After product low-carbon design is characterized by a multi-stage decision process with interaction effects on each other in the product life cycle, a dynamic programming method is used to optimize the total carbon footprint of each stage while considering interaction effects of solutions at each stage in product life cycle. The low-carbon design of a cold heading machine is used to demonstrate the proposed methodology.

Product sustainability is a pressing global issue that requires urgent improvement, and low-carbon design is a crucial approach toward achieving sustainable product development. Digital twin technology, which connects the physical and virtual worlds, has emerged as an effective tool for supporting product design and development. However, obtaining accurate product parameters remains a challenge, and traditional low-carbon product design primarily focuses on design parameters. To address these issues, this paper proposes a method for data collection throughout the product lifecycle, leveraging the Internet of Things. The paper envisions the automatic collection of product lifecycle data to enhance the accuracy of product design. Moreover, traditional low-carbon design often has a limited scope that primarily considers product structure and lifecycle stage for optimization. In contrast, combining digital twin technology with low-carbon design can effectively improve product sustainability. Therefore, this paper proposes a three-layer architecture model of product sustainability digital twin, comprising data layer, mapping layer, and application layer. This model sets the carbon footprint as the iterative optimization goal and facilitates the closed-loop sustainable design of the product. The paper envisions sustainable product design based on digital twins that can address cascading problems and achieve closed-loop sustainable design.

基于土地利用变化的四川省碳排放与碳足迹效应及时空格局

The influence of disclosing product lifecycle carbon footprint information on consumer purchase intentions based on the APE model perspective: An ERP and questionnaire study

Agriculture and animal husbandry increased carbon footprint on the Qinghai-Tibet Plateau during past three decades

In the field of low-carbon design, the collection and quantitative analysis of carbon footprint data are vital for reducing the environmental impact of products. This paper proposes a carbon footprint calculation method based on the product life cycle, using Cleer's STAGE Bluetooth speaker as a case study. By integrating greenhouse gas (GHG) emission data from the GaBi database with the life cycle assessment (LCA) theory and the PAS 2050 standard, a carbon emission quantification model and calculation method for Bluetooth speakers have been developed. Results indicate that the STAGE Bluetooth speaker has a total carbon footprint of 227.01 kgCO₂e across its life cycle. The use stage contributes the most (72.77%, 165.2 kgCO₂e), followed by transportation (25.23%, 57.28 kgCO₂e), raw material acquisition (3.78%, 8.6 kgCO₂e), and production (1.82%, 4.13 kgCO₂e). The recycling of materials results in a net reduction of -3.6% (-8.2 kgCO₂e). The research demonstrates that improving energy efficiency and substituting materials are crucial strategies for reducing the carbon footprint of electronic products. This method offers a theoretical basis for low-carbon design in similar products and serves as a reference for assessing the carbon footprint of other electronic devices in industrial applications.

Land, carbon and water footprints in Taiwan