Life Cycle Inventory Assessment Research Articles

Life cycle assessment of lattice structures: Balancing mass saving and productivity

Additive Manufacturing has revolutionized manufacturing processes, offering design flexibility and advances in various applications. The integration of lattice structures into lightweight designs has attracted attention due to their ability to optimize properties such as stiffness, strength and energy absorption. This paper explores the trade-off between mass reduction and productivity while evaluating the environmental sustainability of lattice structures manufactured with Laser-based powder bed fusion for metals Using Life Cycle Assessment, two design variants for an automotive component are compared: a topologically optimized version with a solid bulk section, and a second design with lattice structures for additional weight reduction. Experimental measurements and a detailed analysis of the laser strategy were performed to build the Life Cycle Assessment inventory. The integration of lattice structures allowed a weight reduction of 6 %, but resulted in a significant decrease in productivity and a higher environmental impact. Surprisingly, lattice geometries, often perceived as green solutions, can have negative sustainability implications due to longer manufacturing times and impact of auxiliary equipment. Successful implementation of environmentally sustainable designs requires a balance between mass reduction and productivity while addressing potential environmental consequences.

A multi-criteria framework for the ecodesign of bio-based materials at early development stages

Ex-ante life cycle assessment (LCA) allows for a holistic environmental evaluation of novel products at research and development (R&D) stages when the potential for environmental improvement is higher. Multi-criteria decision analysis (MCDA) incorporates techno-economic attributes and considers decision-makers’ (DMs) perspectives. Thus, integrating ex-ante LCA and MCDA is key for R&D ecodesign. This article proposes a framework combining ex-ante LCA with multi-attribute value theory and stochastic multi-acceptability analysis (SMAA) for novel bio-based materials in four steps: i) Problem structuring, ii) LCA scope, inventory, and scale-up, iii) Performance table, elicitation, and MCDA calculations, and iv) Interpretation and recommendations. The LCA-MCDA framework provides a structured way to model upscaled environmental impacts and encompass technical and economic performances in a global value while considering novel materials' potential application and functionality. The framework is applied to lab-scale starch films for food packaging, comparing them with commercial polymers for cost, environmental, and technical criteria according to three DMs' perspectives (biopolymer/sustainability researchers). Materials, formulations, and scenarios are assessed on a 1-kg basis with properties as technical criteria. The commercial films outperform the novel films, primarily due to technical performance. Scale-up and plasticizer scenarios show potential for reducing environmental impacts but do not alter the ranking of alternatives. SMAA shows that the ranking highly depends on the criterion weights; conversely, individual DM's perspectives lead to similar results. Materials are also compared for equivalent properties (stiffness, strength, and moisture barrier) by applying material substitution factors. The most favorable results for the starch films are achieved for equivalent stiffness, thus suggesting further investigation for rigid applications. Furthermore, suggestions for applying the framework to other cases are provided. The LCA-MCDA framework facilitates the communication of LCA results with cost and technical performance, supporting R&D in dealing with trade-offs and identifying pathways toward more sustainable and competitive production of bio-based materials.

Integrated environmental accounting of a geothermal grid

The worldwide energy consumption shows a significant increasing demand and is still projected to grow in the next years. This is causing increased pollution and environmental degradation. The energy sector is one of the major contributors to the emissions of greenhouse gases and pollutants. A fair access for everyone to energy sources capable of meeting the global needs without further degrading the ecosystems is of paramount importance. In this work, a sustainable medium enthalpy geothermal system to produce electric and thermal energy is assessed. The case study is located in Campania region, Southern Italy, in an area famous for its volcanic activity. The system is composed by an Organic Rankine Cycle for electricity production and a grid for district heating and cooling. The environmental performances are assessed using the Emergy Accounting (EMA) systemic approach. The calculation of the EMA conversion factors, the so-called Unit Emergy Values (UEVs), could benefit from the use of appropriate inventories. The databases used within the Life Cycle Assessment (LCA) method provide a huge amount of reliable, peer reviewed inventories. This work proposes the use of LCA inventories to calculate UEVs, comparing them to literature ones. The performance of the investigated system is calculated and compared to current and improved strategies for heating and cooling and electricity production. The calculated UEVs seem to be reliable when compared to literature values, strengthening the link between LCA and EMA methods. The obtained results confirm the environmental feasibility of the analyzed system and its beneficial environmental performance, when compared to fossil based and other renewable energy production systems. The electricity, heating and cooling produced by the investigated system has UEV values of respectively 1.0E+04, 7.6E+03 and 1.1E+04 sej/J, validating its fitness within a perspective of improved sustainability.

Life cycle assessment of microgreen production: effects of indoor vertical farm management on yield and environmental performance

The global production of plant-based foods is a significant contributor to greenhouse gas emissions. Indoor vertical farms (IVFs) have emerged as a promising approach to urban agriculture. However, their environmental performance is not well understood, particularly in relation to operational choices where global warming potentials (GWP) can vary between 0.01–54 kg CO2e/kg−1 of leafy greens produced. We conducted a life cycle assessment (LCA) of a building-integrated IVF for microgreen production to analyse a range of operational conditions for cultivation: air temperature, CO2 concentration, and photoperiod. We analyzed a dynamic LCA inventory that combined a process-based plant growth model and a mass balance model for air and heat exchange between the chamber and the outside. Results showed that the GWP of IVFs can vary greatly depending on the operation conditions set, ranging from 3.3 to 63.3 kg CO2e/kg−1. The optimal conditions for minimizing GWP were identified as 20 ℃, maximum CO2 concentration in the chamber, and maximum photoperiod, which led to a minimum GWP of 3.3 kg CO2e/kg−1 and maximum production of 290.5 kg fresh weight week-1. Intensification of production thus led to lower impacts because the marginal increase in yield due to increased resource use was larger than the marginal increase in impact. Therefore, adjusting growing conditions is essential for the sustainability of urban food production.

Characterization Factors to Assess Land Use Impacts on Pollinator Abundance in Life Cycle Assessment.

While wild pollinators play a key role in global food production, their assessment is currently missing from the most commonly used environmental impact assessment method, Life Cycle Assessment (LCA). This is mainly due to constraints in data availability and compatibility with LCA inventories. To target this gap, relative pollinator abundance estimates were obtained with the use of a Delphi assessment, during which 25 experts, covering 16 nationalities and 45 countries of expertise, provided scores for low, typical, and high expected abundance associated with 24 land use categories. Based on these estimates, this study presents a set of globally generic characterization factors (CFs) that allows translating land use into relative impacts to wild pollinator abundance. The associated uncertainty of the CFs is presented along with an illustrative case to demonstrate the applicability in LCA studies. The CFs based on estimates that reached consensus during the Delphi assessment are recommended as readily applicable and allow key differences among land use types to be distinguished. The resulting CFs are proposed as the first step for incorporating pollinator impacts in LCA studies, exemplifying the use of expert elicitation methods as a useful tool to fill data gaps that constrain the characterization of key environmental impacts.

Sustainability of photovoltaic technologies in future net‐zero emissions scenarios

AbstractPhotovoltaic installed cumulative capacity reached 849.5 GW worldwide at the end of 2021, and it is expected to rise to 5 TW by 2030. The sustainability of this massive deployment of photovoltaic modules is analysed in this article. A literature review, completed with our own research for emerging technologies has been carried out following life cycle assessment (LCA) methodology complying with ISO 14040 and ISO 14044 standards. Different impact categories have been analysed for five commercial photovoltaic technologies comprising more than 99% of current market (crystalline silicon ~94% and thin film ~6%) and a representative of an emerging technology (hybrid perovskite). By using data from LCA inventories, a quantitative result for 15 impact categories has been calculated at midpoint and then aggregated in four endpoint categories of damage following ReCiPe pathways (global warming potential, human health damage, ecosystems damage and resources depletion) in order to enable a comparison to other renewable, fossil fuel and nuclear electricity production. In all categories, solar electricity has much lower impacts than fossil fuel electricity. This information is complemented with an analysis of the production of minerals with data from the British Geological Survey; the ratio of world production to photovoltaic demand is calculated for 2019 and projected to 2030, thus quantifying the potential risks arising from silver scarcity for c‐Si technology, from tellurium for CdTe technology and from indium for CIGS and organic or hybrid emerging technologies. Mineral scarcity may pose some risk for CdTe and CIGS technologies, while c‐Si based technology is only affected by silver dependence that can be avoided with other metals replacement for electrodes. When the risks grow higher, investment in recycling should boost the recovery ratio of minerals and other components from PV module waste.

Automated Life cycle inventories for existing buildings – a parametric reference model approach

Buildings account for 40% of global Greenhouse gas (GHG) emissions. In heating-dominated climates, most building-related emissions originate from building stock operational energy, especially from buildings constructed before energy requirements were introduced. Renovation can mitigate operational emissions, however, materials should be included to increase the mitigation potential. Life-cycle assessment (LCA) includes emissions from materials and energy but are time-consuming in renovations because BIM-aided approaches for automating inventories are inaccessible for existing building fabric. This paper proposes a parametric inventory-generator for existing buildings, which defines material quantities through few key variables, which are accessible in early design stages, and which relate to a reference model for a specific building type. The generated model includes LCA inventory data such as service life, replacements, and End of Life from a generic impacts database. The model is adjustable and can be supplied with predefined renovation interventions and new components. The proposed simplification has potential to facilitate modelling of LCA inventories for every existing building, and makes LCA feasible for more than deep renovations, offering a base for the proposed renovation pass by the EU commission. Future research will add building types and explore implementing default inventories based on cadastre data as public resource.

Regionalized chemical footprint method to identify aquatic ecotoxicity hotspots of hard disk drive rare-earth magnets.

The chemical footprint (ChF), which combines life cycle assessment (LCA) and quantitative risk assessment principles, shows promise for exploring localized toxicity impacts of manufacturing processes, which is not achievable with LCA alone. An updated ChF method was applied to the global annual production of a hard disk drive (HDD) rare-earth element (REE) magnet assembly, assuming a supply chain in East and Southeast Asia. Existing REE magnet assembly LCA inventories were combined with supplier manufacturing locations to create a cradle-to-gate spatial unit process inventory. Emissions from the electricity grid for each manufacturing site were downscaled to hydrobasins of interest using the Global Power Plant Database. The predicted no effect concentration (PNEC) was chosen as the ecotoxicity pollution boundary to determine the threshold for dilution of each chemical of concern (CoC) and to calculate the ChF. Finally, a high-resolution hydrological database provided volumes of the freshwater river reach draining each hydrobasin and was used to calculate the dilution capacity (DC), that is, the volume required to remain at or below the PNEC for each CoC. The total ChF of annual REE magnet assembly production was 6.91E12 m3 , with hotspots in watersheds in China and Thailand where REEs are processed and steel metalworking takes place. Metals were the primary CoCs, with cadmium and chromium(VI) comprising 77% of total ChF. Dilution factors ranged from 5E-09 to 9E + 03 of the DC of the waterbody, reflecting the spatial variability in both emissions and DC. An advanced ChF method was demonstrated for HDD REE magnets. Scoping is a key step required to reduce model complexity. The use of regionalized fate factors and standardized hydrological data sets improves the comparability of ChFs across hydrobasins. Additional work to combine data sets into readily available tools is needed to increase usability and standardization of the ChF method and promote wider adoption. Integr Environ Assess Manag 2023;19:272-283. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Integrated Carbon Footprint and Economic Performance of Five Types of Dominant Cropping Systems in China’s Semiarid Zone

Crop production requires large areas of land and makes an important contribution to greenhouse gas emissions. Cleaner production of all crop types could be of great significance to realizing carbon neutrality as soon as possible. The present study adopted life cycle assessment (LCA) combined with the profit accounting method of input-output to compare the differences in greenhouse gas emissions in the entire life cycle of apple (Malus pumila Mill.), grain maize (Zea mays L.), wheat (Triticum aestivum L.), silage maize (Zea mays L.), and alfalfa (Medicago sativa Linn.) production in eastern Gansu Province with three functional units, including per ha of land, per ton of product, and per 10,000 yuan of output value. The results showed that apple had the largest carbon footprint per ha. Wheat had the largest carbon footprint per ton of product and per 10,000 yuan output. The results of LCA inventory sensitivity analysis showed that the main sources of greenhouse gas emissions for all crops were the production process of agricultural materials such as chemical fertilizer, machinery, and agricultural film. In particular, the excessive input of chemical fertilizer was the driving factor resulting in greenhouse gas emissions. Based on the study results, this paper also puts forward certain suggestions on the future land use of the cropping systems in the study area.

Comparing greenhouse gas emissions and nutritional values based on Korean suggested meal plans and modified vegan meal plans.

Producing animal products from farm to table emits massive amounts of greenhouse gases (GHGs). Modified meal plans, mainly including vegetables and grains, have been recommended to reduce GHG emissions. However, these meal plans have not been developed with regard to the micronutrient content, but rather with regard to the energy requirements of grains and vegetables, which could result in a nutritional imbalance. For this reason, we investigated a common Korean suggested meal plan (SMP) from the National Institute of Agricultural Sciences, in which nutritional conditions were considered, and evaluated its GHG emissions using the Life Cycle Assessment Inventory Database and nutritional values. The SMP, which included meat, was based on the Korean Nutrition Society for adult men age 19 to 29, and was changed to a vegan meal plan (VMP). Animal-based protein sources were substituted for meat alternatives, such as beans and tofu, for which carbon footprint data was available. To compare the nutritional differences, the 9th Korean Food Composition Tables I and II were consulted. To calculate GHG emissions, the carbon footprint data of the food was converted to a CO2 equivalent (CO2e) using a procedure from the Foundation of Agriculture Technology Commercialization and Transfer. It was found that GHG emissions per calorie were 18% lower for the VMP when compared to the SMP. However, if GHG emissions per total amino acids were evaluated, the VMP GHG emissions per total amino acids were 0.12 g CO2e/mg, while the corresponding value for the SMP was 0.06 g CO2e/mg. The Korean daily meat intake reported by the Korea Agricultural Statistics Service was 37.1% lower than in the SMP, but when converted to a protein intake the figure was 17.0% lower. It was found that each SMP resulted in more GHG emissions than the VMP, but when considered as GHG emissions per total amino acids, the opposite pattern was apparent. There is a need to conduct more detailed studies of the variation in GHG emissions with different meal plans, using the daily meat intake per person.

Integration of life cycle assessment, artificial neural networks, and metaheuristic optimization algorithms for optimization of tomato-based cropping systems in Iran

The main purpose of this study was to evaluate the use of an integrated life cycle assessment (LCA), artificial neural network, and metaheuristic optimization model to improve the sustainability of tomato-based cropping systems in Iran. The model outputs the combination of input usage in a tomato cropping system, which leads to the highest economic output and the least environmental impact. The LCA inventory was created using data from 114 open-field tomato farms in the Alborz Province of Iran during one growing period in 2015. Among all management components, the main focus was on irrigation management systems. The optimization problem was designed by integrating three indicators: carbon footprint (CF), benefit-cost ratio (BCR), and energy use efficiency (EUE) as the objective of field tomato production. The functional unit was 1 kg of tomato aligned with the system boundary of the cradle to market life cycle. Three artificial neural networks (ANNs) were applied to model relationships between the inputs and three indices (CF, BCR, and EUE) as the objective functions. Multi-objective genetic algorithm (MOGA) and multi-objective particle swarm optimization (MOPSO) were used to minimize the CF and maximize the BCR and EUE indicators. The abovementioned aims have been pursued by developing codes in MATLAB software. CF, BCR, and EUE were calculated to be 0.26 kg CO2−eq (kg tomato)−1, 1.8, and 0.5, respectively. MOGA results envisage the possibility of an increase of 86% and 50% in the EUE and BCR and a 43% reduction in the CF of tomato production systems. Moreover, EUE and BCR increased by 83% and 49%, and CF was reduced by 39% from the optimum results obtained from the MOPSO algorithm. It was revealed that in order to optimize field tomato production with the target objectives of this study, a large additional use for irrigation pipes, plastic, and machinery in comparison to current situation is required, while a large reduction of biocide, chemical fertilizer, and electricity consumption is indispensable. According to the results of our study, it was concluded that the optimal solutions require a modernization of irrigation systems and a decrease in the consumption of chemical fertilizers and pesticides. The implementation of management options for such solutions is discussed.

Give them credit‐the greenhouse gas performance of regional biogas systems

AbstractAnaerobic digestion to produce biogas is an important decentralised renewable energy technology. Production varies extensively between different countries and within countries, as biogas production is heavily dependent on local and regional feedstocks. In Germany, distinct regional differences can be observed. Therefore, understanding the kinds of biogas systems operating within a region is crucial to determine their greenhouse gas (GHG) mitigation potential and carbon neutrality. This is the first study to conduct an integrated life cycle assessment of biogas configurations in the landscape (biogas plants and their biomass catchments) for an entire region. RELCA a ‘REgional Life Cycle inventory Assessment’ approach was used to model the GHG mitigation potential of 425 biogas plants in the region of Central Germany (CG), aggregated to nine biogas clusters, based on feedstock mix (e.g. animal manures and energy crops) and installed capacity. GHG emission profiles were generated to compare and to identify the role of GHG credits and size of installed capacity on the mitigation performance of the regional biogas clusters. We found that smaller scaled slurry dominant clusters had significantly better GHG mitigation performance (−0.1 to −0.2 kg CO2eq kWhel−1), than larger energy crop dominant (ECdom) clusters (0.04–0.16 kg CO2eq kWhel−1), due to lower cultivation emissions and larger credits for avoided slurry storage. Thus, for the CG region larger ECdom clusters should be targeted first, to support GHG mitigation improvements to the overall future electricity supplied by the regional biogas systems. With the addition of GHG credits, the CG region is producing biogas with GHG savings (−0.15 kg CO2eq kWhel−1, interquartile range: 0.095 kg CO2eq kWhel−1). This infers that biogas production, as a waste management strategy for animal manures, could have important ramifications for future policy setting and national inventory accounting.

Life Cycle Assessment of Large-scale Compressed Bio-natural Gas Production in China: A Case Study on Manure Co-digestion with Corn Stover

Compressed bio-natural gas (CBG) production from large-scale systems has been recognized as promising because of the abundance of manure and crop residue feedstocks and its environmental friendliness. This study is a life cycle assessment using the local database of an operating large-scale CBG system of manure co-digestion with corn stover in China and eBalance software. The results showed that the system’s Primary Energy Input to Output (PEIO) ratio was 20%. Its anaerobic digestion process was the main contributor to energy consumption, accounting for 76%. Among the six environmental impacts investigated in this study, the global warming potential (GWP) was the major environmental impact, and the digestate effluent management process was the main contributor to the GWP, accounting for 60%. The mitigation potential of the system, compared with reference case for GWP, was 3.19 kg CO2-eq for 1 m3 CBG production. In the future, the GWP mitigation could be 479 × 106 metric tons CO2-eq with 150 × 109 m3 yr−1 CBG production from the entire China. This study provides a reference on large-scale CBG production system for establishing a localized life cycle assessment inventory database in China.

Life cycle assessment of asphalt pavement recycling for greenhouse gas emission with temporal aspect

Abstract This paper quantifies greenhouse gas emission of asphalt pavements containing reclaimed asphalt pavement using life cycle assessment with temporal aspect. The life cycle stages include raw material acquisition, plant production, construction, maintenance, and end-of-life. The time-dependent decay function of carbon dioxide was adopted to capture time effect in life-cycle inventory assessment. The case study of runway rehabilitation demonstrates that four critical factors may affect environmental impact of pavement recycling, including recycled material content, blending efficiency of virgin and recycled binder, moisture content of recycled aggregate, and pavement performance levels. As recycled material content increases, the reduction of greenhouse gas emission increases accordingly. However, the benefits of raw material saving can be compensated by the increased moisture content of recycled aggregate and the shorter life of pavement with reclaimed asphalt pavement. As the moisture content of recycled aggregate increases, the performance of recycled asphalt pavement need reach a higher level in order to avoid environmental burden. On the other hand, the results indicate that the environmental impact of asphalt pavement recycling is overestimated if temporal aspect is not considered. This finding reinforces the importance of physical decay pattern of greenhouse gas emissions along time in life cycle assessment for global warming potential.

Environmental assessment at the urban level combining LCA-GIS methodologies: A case study of energy retrofits in the Barcelona metropolitan area

This study proposes a combined life cycle assessment (LCA) and Geographical Information Systems (GIS) methodology to develop complex LCA inventories for multiple applications. The study focusses on the environmental implications of buildings retrofits, especially in the European context, where the building sector is one of the largest energy consumers. In this context, a new and holistic perspective is needed that expands from the building scale to the urban scale.The combination of LCA and GIS methods includes the development of an urban characterization model based on bottom-up methodologies. The environmental implications associated with increasing the thermal insulation of existing buildings to the current standard are determined based on LCA methods. In this step, common construction systems for building retrofits are used, and insulation materials are compared. Then, absolute and relative extrapolations are performed considering different urban morphologies.The results confirm the importance of the energy retrofitting of residential buildings in large functional urban areas such as the Barcelona metropolitan area, which is examined as a case study. The LCA results indicate that the selection of proper construction systems and thermal insulation materials is important to the environmental performance of building retrofits, and these selections can lead to CO2 emission differences of up 16% in the region. The relative extrapolation results indicate significant environmental differences between urban morphologies. The LCA results show the potential strategic impacts of the inclusion of LCA methods in retrofit policies at the urban scale.

Life Cycle Inventory Assessment as a Sustainable Chemistry and Engineering Education Tool

Chemists and chemical engineers are involved in and responsible for the life of a product from the discovery stage to manufacturing, market introduction, and end of life. They participate in and contribute to all segments of the supply chain, from cradle to grave. In the industrial sector, they work hand in hand with other professionals in engineering, business, intellectual property, and environmental safety and health. To better prepare students to understand industry-focused grand challenges and contribute to the long-term sustainability of the enterprise, we designed a course for advanced undergraduate and graduate students in the Schools of Chemistry & Biochemistry and Chemical & Biomolecular Engineering at the Georgia Institute of Technology. The pilot class of 26 students was introduced to chemical manufacturing, the eight sustainability grand challenges, intellectual property, regulatory and registration, and process hazard and safety. Invited speakers from industries such as Albemarle, BASF, Dow,...

Life cycle assessment of a future central receiver solar power plant and autonomous operated heliostat concepts

Abstract Up-scaling in power plant size and new innovative concepts in the solar field design are among the most promising ways to reduce the costs of future concentrated solar tower power plants. Besides the economic benefits, the knowledge about the ecological impacts of new concepts is of increased interest in view of the climate targets set. This paper aims to assess the ecological impacts of two autonomous operated heliostat concepts within a future solar tower power plant. Both concepts include a photovoltaic (PV) energy supply for the heliostats, combined with either an LiFPO4 or an LiNMC battery system. Both are compared with a conventional energy supply system. The analysis for comparing the different heliostat concepts is embedded in a life-cycle assessment (LCA) of a 440 MW solar tower plant with a 12,166 MWhth molten salt thermal storage. For the solar tower power plant and the autonomous operated heliostat concepts new LCA inventories were developed. The environmental impacts assessed include the Global Warming Potential (GWP), which is found between 15 and 105 gCO2eq/kWhel, for the entire solar plant depending on the share of fossil fuel co-firing. Indirect life cycle emissions excluding fossil fuel co-firing and thus associated with the life-cycle of the power plant components show, that the conventional solar field is the main contributor to GWP with 9.5 gCO2eq/kWhel. Results for both autonomous concepts demonstrate, that reductions in the impact on climate change are at about 10% compared to the solar field with conventional heliostats. Thus it is demonstrated, that heliostat concepts with an autonomous renewable energy supply lead to considerable reductions in life cycle emissions.

Incorporating denitrification-decomposition method to estimate field emissions for Life Cycle Assessment

This study focuses on a detailed Life Cycle Assessment (LCA) for flax cultivation in Northern France. Nitrogen related field emissions are derived both from a process-oriented DeNitrification-DeComposition (DNDC) method and the generic Intergovernmental Panel on Climate Change (IPCC) method. Since the IPCC method is synthesised from field measurements at sites with various soil types, climate conditions, and crops, it contains significant uncertainties. In contrast, the outputs from the DNDC method are considered as more site specific as it is built according to complex models of soil science. As it is demonstrated in this paper the emission factors from the DNDC method and the recommended values from the IPCC method exhibit significant variations for the case of flax cultivation. The DNDC based emission factor for direct N2O emission, which is a strong greenhouse gas, is 0.25–0.5%, significantly lower than the recommend 1% level derived from the IPCC method. The DNDC method leads to a reduction of 17% in the impact category of climate change per kg retted flax straw production from the level obtained from the IPCC method. Much higher reductions are recorded for particulate matter formation, terrestrial acidification, and marine eutrophication impact categories. Meanwhile, based on the DNDC and IPCC methods, a comparative LCA per kg flax straw is presented. For both methods sensitivity analysis as well as comparison of uncertainties parameterisation of the N2O estimates via Monte-Carlo analysis are performed. The DNDC method incorporates more relevant field emissions from the agricultural life cycle phase, which can also improve the quality of the Life Cycle Inventory as well as allow more precise uncertainty calibration in the LCA inventory.

Life cycle inventory assessment of carrot crops in France

Life cycle inventory assessment of carrot crops in France

A step toward regionalized scale‐consistent agricultural life cycle assessment inventories

Life cycle inventory (LCI) regionalization (i.e., the determination of input and output flows from production processes at a subcountry scale) is a priority in life cycle assessment (LCA) studies, particularly in the agri-food sector. Many regionalized LCAs fail to ensure that microlevel inventories are consistent with country-level aggregated data-or "scale consistent." They also fail to construct LCIs using international reference guidelines and trustworthy standardized data sources. This failure generates inaccuracies and biases in inventories and can compromise comparability among international LCA studies. Our study introduces scale consistency as a principle for regionalized agri-food LCIs. We present a generic procedure that defines how scale-dependent LCI flows should be regionalized, depending on data availability. We then present a list of inventory flows that require regionalization and their suggested calculation procedures (methods and models) from 2 methodological guides developed by projects Agribalyse and World Food LCA Database. As proof of concept, we apply the procedure to Portugal and assess whether the methods and models proposed for each type of inventory flow in both guides can potentially be applied consistently with the data available. For 17 inventory flows, we apply calculated scale-consistent inventory flows for Portuguese agriculture, covering 260 products that can be used in future LCA studies. Comparing results with international databases, we show that this procedure can improve country-level estimates significantly. Our study is the first step in introducing scale consistency as a guiding principle for regionalized LCIs for agri-food LCA studies. Integr Environ Assess Manag 2017;13:939-951. © 2017 SETAC.