Hybrid Life Cycle Assessment Research Articles

The Façade of Green Lifestyles: Outdoor Recreation and Greenhouse Gas Emissions in Norway

Outdoor recreation is a popular leisure activity many consider to be an environmentally friendly practice that promotes care for the natural world. This study uses a survey to investigate transportation use and gear purchasing habits among Norwegians who participate regularly in outdoor life. Using a hybrid life-cycle assessment, it was estimated that the average participant releases between 3.4 and 4.7 tons of carbon dioxide equivalent emissions per year due to outdoor recreation activities. This is equal to around one fifth of the average Norwegian’s yearly greenhouse gas emissions and is more than double the per capita boundary required to limit global temperature rise to 2 degrees Celsius. Regression analysis highlights level of disposable income as the best predictor of environmental load. This indicates that the façade of a green lifestyle based on ecological values masks the global environmental consequences of excessive consumption related to outdoor recreation activities.

A household-scale life cycle assessment model for understanding the food-energy-water nexus

The household is an important locus of decision-making regarding food, energy, and water (FEW) consumption. Changes in household FEW consumption behaviors can lead to significant reductions in environmental impacts, but it can be difficult for consumers to compare the relative impacts of their consumption quantitatively, or to recognize the indirect impacts of their household consumption patterns. We describe two novel tools designed to address this problem: A hybrid life cycle assessment (LCA) framework to translate household consumption of food, energy, and water into key environmental impacts including greenhouse gas emissions, energy use, and water use; and a novel software application called HomeTracker that implements the framework by collecting household FEW data and providing environmental impact feedback to households. We explore the question: How can a life cycle assessment-based software application facilitate collection and translation of household consumption data to meaningful environmental impact metrics? A case study in Lake County, Illinois is presented to illustrate use of the HomeTracker application. Output data describing environmental impacts attributable to household FEW consumption in the study area are shown in order to illustrate key features and trends observed in the case study population. The framework and its associated output data can be used to support experimental research at the household scale, allowing for examination of what users purchase and consume over an extended period of time as well as increased understanding of household behavior trends and environmental impacts, and as future work.

Carbon footprints of travel to World Heritage Sites: communicating climate to potential tourists through a consumption-based life-cycle assessment

ABSTRACT In this study, an input-output-based hybrid life cycle assessment method is used to calculate the carbon footprint of a tourist’s travel to sixteen United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Sites (WHS) including direct and indirect emissions. The carbon footprint of three trip styles (budget, mid-range expenses, and high-end) is calculated for each WHS, reflecting options available to heritage tourists. This study is part of a more extensive study that created a climate communication recognition scheme (CCRS) for UNESCO WHS to communicate information about climate change to potential tourists and heritage site managers, elaborating and extending upon communication tools such as environmental product information schemes, certifications, and ecolabels. The results are intended for educational purposes and contribute to a holistic approach to carbon management in heritage tourism. The results are available online as an ArcGIS StoryMap titled Climate Footprints of Heritage Tourism.

Understanding the link between industrial stimulation effect and environmental impact of sponge city: With a focus on the construction phase

‘Sponge City’ has been widely accepted as a green transformation direction of China's urbanization. Such a mid-to long-term construction strategy will bring about prominent economic stimulation effects and complicated environmental impacts, whereas the research is far from sufficiency. This study developed a methodology based on the Hybrid Life Cycle Assessment to quantify the impact of the entire supply chains and relevant pollution processes, by disaggregating nine Sponge City construction sub-sectors from the construction sector in Input-Output table and parameterizing a specific environmental matrix focusing on water and air pollutants and CO2 emission. Taken the Sponge City pilot area of Pingxiang City as a case, the evaluation of direct and overall industrial stimulation effects and embodied pollutant discharges, as well as analysis of the implicit connections, were carried out. It is found that the total inputs stimulated by Sponge City construction could reach 4.4 times of the direct input, while pollution involved by the supply chains amounts to 3%∼6% of total emission of the pilot city. The primary industry providing direct input and the service industries as indirect supporters became the main sources of water pollution. Although the inputs from the secondary industry brought about a more remarkable industrial stimulation effect, direct and indirect inputs from non-metallic mineral products, indirect inputs from metal products and the electricity industry led to noteworthy air pollution problems and global warming potential. The outcomes help promote more holistic understanding of the Sponge City construction as an emerging industry and facilitate comprehensive decisions for the sake of sustainable urban development.

Emissões de carbono das famílias brasileiras por meio da POF e da matriz de insumo-produto

Abstract This study aims to comprehensively assess the carbon footprint of Brazilian households using data from the 2008 and 2018 Household Budget Survey (POF). Employing a hybrid Life Cycle Assessment methodology, our analysis reveals noteworthy insights. In 2008, households within the lower income bracket emitted approximately 4.04 tCO2e/year, decreasing to 3.81 tCO2e/year by 2018. Conversely, higher-income households emitted significantly more, with emissions of around 28.73 tCO2e/year in 2008, decreasing to 25.94 tCO2e/year by 2018 - almost seven times the emissions of their lower-income counterparts. Intriguingly, although constituting merely 2.47% of all families in 2018, the wealthiest households were responsible for 8.31% of total emissions, while the poorest, representing 24.25%, contributed to 11.97% of emissions. The imperative for affluent families, who exert a disproportionate environmental impact, lies in reconsidering consumption habits and actively seeking low-emission alternatives to curtail their carbon footprint.

69 Animal Sourced Foods Role in Sustainable Nutrition

Abstract Amid growing concern regarding the food system are calls to reduce or eliminate animal sourced foods (ASF) from human diets. Despite the green revolution and consequent increase in crop yields, nutrient deficiencies are still problematic, particularly in developing regions. In the US, ASF provide 24% of energy, 48% of protein, approximately 50% of the essential amino acids and essential fatty acids as well as the micronutrients (White and Hall, 2017). This presentation introduces a framework for evaluation and discusses remaining knowledge gaps regarding the role of ASF in sustainable food systems that provide nutritious diets. Lifecycle assessment (LCA) was used to provide an accounting of environmental and sustainability characteristics of food production systems. LCA has an explicit goal the identification of tradeoffs between stages in the supply chain and tradeoffs across environmental dimensions. In a published study (Kim et al., 2020) using a hybrid lifecycle assessment technique, it was shown that while vegetarian diets resulted in lower environmental impacts across several environmental categories, that the US non-vegetarian recommended dietary guidelines led to increases for many categories. This is driven by the increased consumption of less calorically dense foods and changes in the patterns of food loss and waste. Ongoing studies of US beef production systems are providing insight into factors behind the variability in sustainability driven by practice and location. One management practice receiving attention is Adaptively Managed Paddocks (AMP). Sequestration estimates were combined with process model simulations of cow calf finishing operations. One system used conventional grain finishing and the other used grass finishing. The potential mitigation of GHG emissions from the potential sequestration is significant. Complete assessment of the role of ASF in healthy diets from sustainable food systems requires a full understanding of the benefits and costs of alternatives and informed decisions based on understanding of tradeoffs.

When will China's passenger vehicle sector reach CO2 emissions peak? A life cycle approach based on system dynamics

The Chinese automobile industry is taking steps to reduce sectoral carbon dioxide (CO 2 ) emissions by electrifying the passenger vehicle fleet in light of the carbon emission peak commitment. As most studies either focus on the fuel use or apply static inputs, there is a lack of dynamic fleet-based analysis considering every life-cycle phase. In this study, a hybrid life-cycle assessment is combined with a system dynamics model to simulate changes in the number of vehicles in different life-cycle phases in order to produce a more accurate estimation of sectoral CO 2 emissions and the peak time for the passenger vehicle sector. The detailed data on vehicle sales, in use, and disposal is collected, and a scenario analysis is constructed, considering two crucial factors: the future market share of electric vehicles (EV) and projected improvements in fuel consumption. The results indicate that for different market shares, peak time is estimated to be between 2029 and 2031, with sectoral CO 2 emissions peak ranging from 1196 to 1253 million tons. However, if fuel consumption does not improve as in the real world, the passenger vehicle sector will be unable to reach the CO 2 emissions peak within the simulation period, ending up with 1513 million tons by 2035, despite the sectoral CO 2 emissions curve appearing smooth in the simulation period's final years. These findings suggest that the market share of EVs has a modest impact on CO 2 emissions, and fuel consumption is more crucial for achieving the peak. There is a need to establish a public platform to monitor the gap between certified and real-world fuel consumption.

Hybrid life cycle assessment at the neighbourhood scale: The case of Ydalir, Norway

The focus of this study is Ydalir, a neighbourhood in Norway currently in the early planning stages. Ydalir aims to produce its energy locally based on renewable sources, has passive house standards or higher for all its buildings, uses timber or other materials with low embodied greenhouse gas emissions (EGHGE) as its main building materials and prioritises low emissions solutions for the mobility of its inhabitants. Because of those characteristics, the EGHGE related to the operational phases at Ydalir will be low and the relative importance of the EGHGE related to the materials will increase. The EGHE at Ydalir should thus be quantified in a comprehensive manner. Hybrid life cycle assessment (hLCA), which combines process-based life cycle assessment (pLCA) with economic input-output (IO) data is well-suited for this task because a better system boundary completeness is achieved while maximizing the use of typically more reliable process data. Regionalized (Norway) hybrid EGHGE coefficients are compiled for all the main construction materials. The proportion of the IO data (10–78%, average of 34%, and median of 24%) demonstrates the signification truncation associated with traditional pLCA. The EGHGE related to the construction materials, the transport needed along the value chains and to the construction site, and the use of fossil fuels along the value chains (in particular coal) is significant and must be addressed as part of a holistic approach to reducing the EGHGE of our buildings and neighbourhoods, in- and out-land.

Carbon footprint of drinking water over treatment plant life span (2025–2075) is probably dominated by construction phase

Drinking water companies must limit their effects on climate change. Therefore, in this study, we conducted a hybrid life cycle assessment (LCA) for a new drinking water treatment plant (DWTP) to be built in 2025 and expected to be operational until 2075. We focused on obtaining a nearly complete carbon footprint (CF), including both construction (activities and materials) and operation phases. We compared three DWTP concepts: (i) conventional treatment followed by granular activated carbon (GAC) and ultrafiltration; (ii) conventional treatment followed by reverse osmosis; and (iii) capillary nanofiltration followed by GAC. As the DWTP is to be built in The Netherlands, we considered the current plans of the European Union for reducing CFs using two future scenarios (reductions of 80% and 100% in 2050). We found that the CF of the construction over the lifetime of the DWTP accounts for 20–70% of the total (excluding beneficial effects), depending mainly on the electricity used (Dutch mix, solar, or wind) and the future scenario. This means that the construction phase should be investigated in detail to obtain a complete and accurate estimate of the total CF of drinking water production for new DWTPs. • Life cycle assessment (LCA) of a future DWTP was conducted. • We focused on carbon footprint (CF) and construction and use phases were included. • We considered the EU path to become carbon neutral by 2050. • The CF of construction widely varies and can be 20–70% of the total. • The CF of the construction phase should be investigated in detail in LCAs.

Toward a Sustainable Municipal Solid Waste Incineration Fly-Ash Utilization Network: Integrating Hybrid Life Cycle Assessment with Multiobjective Optimization

Toward a Sustainable Municipal Solid Waste Incineration Fly-Ash Utilization Network: Integrating Hybrid Life Cycle Assessment with Multiobjective Optimization

Impacts of Energy Transition on Life Cycle Carbon Emission and Water Consumption in Japan’s Electric Sector

The United Nations (UN) proposed the Sustainable Development Goals (SDG 17) in 2015, together with The Paris Agreement endorsed by 195 signatories and state parties, to address sustainable development-related issues through ambitious and dynamic actions. The transition of the energy system is at the heart of greenhouse gas (GHGs) mitigation which is required to achieve those goals and the electric sector is the core of energy system of interest while the GHG with the largest contribution to rising temperature is carbon dioxide. However, in addition to being centrally relevant for carbon emissions, the electric sector is also an important water consumer. This study applied a hybrid life cycle assessment (LCA) model with the disaggregated electric sector to investigate the impacts on carbon emission and water consumption of the energy transition in Japan under the Sixth Strategic Energy Plan. The results indicate that the electricity mix under the Nationally Determined Contribution (NDC) scenario can cut 50% of existing carbon emissions while intensifying the water consumption by 36% from the life cycle perspective in which 30% are foreign water footprints. The Kaya identity analysis confirmed this conclusion and explained the impacts of four driving factors (population, economy, electricity intensity, and electricity mix) qualitatively and quantitatively showing that the development of technologies and continuous efforts in energy saving can provide a substantial contribution to sustainable development. The results confirmed that the efforts proposed by Japan’s NDC for emission reduction through an energy transition in the electric sector can meet the expectation of achieving the Paris Agreement goals but will also pose greater challenges to the future global water demand in the energy system and regional water stress.

Energy, water, and environmental impacts assessment of electricity generation in Iran

This paper uses a hybrid life cycle assessment method to assess the energy, water, and environmental impacts of high-voltage electricity generation in Iran based on Cumulative Energy Demand and ReCiPe 2016 methods. The aim is to determine the share of renewable and nonrenewable technologies in the associated impacts in order to inform policymakers about proper mitigation strategies. Assessments based on a cradle-to-gate approach showed that producing 1 kWh high-voltage electricity by Iran’s public sector is accompanied by 511 g-CO2-eq. greenhouse gas emissions, 9.52 MJ energy consumption, and 37 l water use. Natural-gas-firing single-cycle power plants (PPs), followed by natural-gas-firing combined cycle PPs, have the highest contributions to the life-cycle impacts of electricity generation in this country. Moreover, the consumption of liquid fossil fuels (diesel and heavy fuel oil) during the shortage of natural gas in cold seasons further escalates their contributions. The share of wind and hydropower plants in the resulting impacts was trivial by comparison. Findings suggested that an adequate supply of PPs with natural gas during clod seasons can partly lower water and environmental impacts of high-voltage electricity generation, but increasing the share of renewables in the electricity mix can considerably reduce most energy, water, and environment-related impacts.

Recent advances in carbon footprint studies of urban ecosystems: overview, application, and future challenges

Urban ecosystems are complex systems with anthropogenic features that generate considerable CO2 emissions, which contributes to global climate change. Quantitative estimates of the carbon footprint of urban ecosystems are crucial for developing low-carbon development policies to mitigate climate change. Herein, we reviewed more than 195 urban carbon footprint and carbon footprint related studies, collated the recent progress in carbon footprint calculation methods and research applications of the urban ecosystem carbon footprint, analyzed the research applications of the carbon footprint of different cities, and focused on the need to study the urban ecosystem carbon footprint from a holistic perspective. Specifically, we aimed to: (i) compare the strengths and weaknesses of five existing carbon footprint calculation methods [life cycle assessment, input–output analysis, hybrid life cycle assessment, carbon footprint calculator, and Intergovernmental Panel on Climate Change (IPCC)]; (ii) analyze the status of current research on the carbon footprint of different urban subregions based on different features; and (iii) highlight new methods and areas of research on the carbon footprint of future urban ecosystems. Not all carbon footprint accounting methods are applicable to the carbon footprint determination of urban ecosystems; although the IPCC method is more widely used than the others, the hybrid life cycle assessment method is more accurate. With the emergence of new science and technology, quantitative methods to calculate the carbon footprint of urban ecosystems have evolved, becoming more accurate. Further development of new technologies, such as big data and artificial intelligence, to assess the carbon footprint of urban ecosystems is anticipated to help address the emerging challenges in urban ecosystem research effectively to achieve carbon neutrality and urban sustainability under global change.

Environmental benefits of material-efficient design: A hybrid life cycle assessment of a plastic milk bottle

Over a million plastic bottles are bought around the world every minute, 20,000 every second. While there is agreement that single-use plastics should be phased out, records of plastic pollution point in the opposite direction. Until the phasing-out of single-use plastics materialises, there is an immediate opportunity to mitigate the environmental impacts of plastic use through better design, that is to improve material efficiency without affecting function or performance. In this article, we focus on a standard plastic milk bottle, which we redesign based on a previously developed shape factor for the sustainability of forms, achieving a ∼13% material reduction. Environmental benefits are evaluated globally through hybrid life-cycle assessment (LCA) both in the 10 countries in which the original plastic bottle is used and the other 22 countries upstream in the supply chain. Results obtained through hybrid LCA are 17.3% higher than those obtained through process-based LCA. Environmental benefits arising in the 22 countries in the upstream supply chain are twice as much as those observed in the 10 countries where the original bottle is used. Overall, our findings show a potential annual reduction of ∼1.9 Mt CO 2 e, equivalent to approximately 415,000 cars taken off the road, thus proving the substantial and viable benefits that can be achieved by material efficiency through redesign.

How does COVID-19 affect the life cycle environmental impacts of U.S. household energy and food consumption?

The COVID-19 pandemic has reduced travel but led to an increase in household food and energy consumption. Previous studies have explored the changes in household consumption of food and energy during the pandemic; however, the economy-wide environmental implications of these changes have not been investigated. This study addresses the knowledge gap by estimating the life cycle environmental impacts of U.S. households during the pandemic using a hybrid life cycle assessment. The results revealed that the reduction in travel outweighed the increase in household energy consumption, leading to a nationwide decrease in life cycle greenhouse gas emissions (−255 Mton CO2 eq), energy use (−4.46 EJ), smog formation (−9.17 Mton O3 eq), minerals and metal use (−16.1 Mton), commercial wastes (−8.31 Mton), and acidification (−226 kton SO2 eq). However, U.S. households had more life cycle freshwater withdrawals (+8.6 Gton) and slightly higher eutrophication (+0.2%), ozone depletion (+0.7%), and freshwater ecotoxicity (+2.1%) caused by increased household energy and food consumption. This study also demonstrated the environmental trade-offs between decreased food services and increased food consumption at home, resulting in diverse trends for food-related life cycle environmental impacts.

Environmental and economic performances of municipal solid waste incineration fly ash low-temperature utilization: An integrated hybrid life cycle assessment

Detoxification and utilization of municipal solid waste incineration fly ash (MSWIFA) with low temperature pretreatment, low environmental burden and low cost have become more and more popular topics in the world. Based on integrated hybrid life cycle assessment, this study compares the environmental and economic performance of MSWIFA low-temperature utilization with the cement kiln co-processing technique when the scenarios with or without salt recovery were considered. The result shows that the hybrid integrated life cycle assessment captures larger environmental and economic benefits of MSWIFA utilization than traditional method due to extending the system boundary to the entire economy. Especially, the avoiding in global warming, primary energy demand and human toxicity from the economic input-output system account for 15%–53%, 26%–65%, and 93%–96% of total impacts, respectively. Additionally, the hybrid model captures a considerable avoidance of cost for MSWIFA treatment. When adopting salt recovery, except for human toxicity, the environmental credit of low-temperature utilization is 3.19–12.64 times higher than that of cement kiln co-processing. Moreover, because of the saving of chemicals and energy, the environmental and economic credit of scenarios without salt recovery is significantly higher than that of scenarios with salt recovery. Findings of this study provide scientific foundations to promote the low-temperature utilization of MSWIFA, as well as multiple solutions on ash-washing wastewater treatment.

Quantification of Building Carbon Emissions in China a Using Hybrid LCA Model

During their life cycle, buildings not only consume a lot of resources and energy, but also produce a large amount of carbon emissions, which have a serious impact on the environment. In the context of global emissions reduction, the trend has been to low carbon buildings. As a major carbon emitting country, it is urgent to promote emission reduction in the construction industry and to establish a model for carbon emissions and calculation in buildings. To this end, this paper collates life cycle carbon emission calculation methods based on life cycle theory and establishes a mixed life cycle carbon emission calculation model for buildings to provide ideas for low carbon buildings in China. A case study of a hospital in Guangming City, Anhui Province is also conducted to verify the feasibility of the model. The results show that the total carbon emission of the hospital is 43283.66 tCO2eq, with the production phase, construction phase, use and maintenance phase and end-of-life phase accounting for 9.13%, 0.35%, 90.06% and 0.46% of the total carbon emission respectively. An analysis of the factors influencing carbon emissions at each stage is presented, and recommendations are given for corresponding emission reduction measures. The carbon emission calculation model based on the hybrid LCA proposed in this study enables a more comprehensive consideration of carbon emissions in the life cycle of a building, and has implications for the study of building carbon emission calculation.

A Novel Hybrid Life Cycle Assessment Approach to Air Emissions and Human Health Impacts of Liquefied Natural Gas Supply Chain

Global interest in LNG products and supply chains is growing, and demand continues to rise. As a clean energy source, LNG can nevertheless emit air pollutants, albeit at a lower level than transitional energy sources. An LNG plant capable of producing up to 126 MMTA was successfully developed and simulated in this study. A hybrid life cycle assessment model was developed to examine the social and human health impacts of the LNG supply chain’s environmental air emission formation. The Multiregional Input–Output (MRIO) database, the Aspen HYSYS model, and the LNG Maritime Transportation Emission Quantification Tool are the key sources of information for this extensive novel study. We began our research by grouping environmental emissions sources according to the participation of each stage in the supply chain. The MDEA Sweetening plant, LNG loading (export terminal), and LNG transportation stages were discovered to have the maximum air emissions. The midpoint air emissions data estimated each stage’s CO2-eq, NOx-eq, and PM2.5-eq emissions per unit LNG generated. According to the midpoint analysis results, the LNG loading terminal has the most considerable normalized CO2-eq and NOx-eq emission contribution across all LNG supply chain stages. Furthermore, the most incredible intensity value for normalized PM2.5-eq was recorded in the SRU and TGTU units. Following the midpoint results, the social human health impact findings were calculated using ReCiPe 2016 characterization factors to quantify the daily loss of life associated with the LNG process chain. SRU and TGTU units have the most significant social human health impact, followed by LNG loading (export terminal) with about 7409.0 and 1203.9 (DALY/million Ton LNG produced annually), respectively. Natural gas extraction and NGL recovery and fractionation units are the lowest for social human health consequences.

Spatial disparity of life-cycle greenhouse gas emissions from corn straw-based bioenergy production in China

Crop straw can be converted into bioenergy through various conversion pathways. Assessing the spatial disparity of greenhouse gas (GHG) emissions under different bioenergy conversion pathways could support region-specific policy decisions. This study assessed GHG emissions of seven corn straw-based bioenergy conversion pathways across 30 provinces in China, using a hybrid life-cycle assessment method based on a multi-regional input–output model. The results showed that, due to spatial disparity of economic supply chains, life-cycle GHG emissions of seven bioenergy conversion pathways clearly differed across 30 provinces and ranged within 82–439 kg CO2-eq per tonne of fresh corn straw with 80% moisture. Most of the bioenergy conversion pathways yielded GHG mitigation benefits across 30 provinces, except for electricity through biogas burning pathway in 3 provinces and bio-natural gas pathway in 28 provinces. Additionally, due to the spatial teleconnection of economic supply chains, bioenergy production occurring in one province could lead to GHG emissions in other provinces. The highest interprovincial embodied GHG emissions primarily occurred in Shandong. In 2012, the maximum GHG mitigation potential from corn straw-based bioenergy using straw burnt in field and abandoned amounted to 253 million tonne CO2-eq in China and interprovincial embodied GHG emissions amounted to 1.8 million tonne CO2-eq in Shandong. The findings support region-specific policymaking in the selection of suitable corn straw-based bioenergy conversion pathways and national policies for the promotion of interprovincial collaboration to reduce bioenergy-related GHG emissions.

Price Variance in Hybrid-LCA Leads to Significant Uncertainty in Carbon Footprints

Hybrid Life Cycle Assessment (HLCA) methods attempt to address the limitations regarding process coverage and resolution of the more traditional Process- and Input-Output Life Cycle Assessments (PLCA, IOLCA). Due to the use of different units, HLCA methods rely on commodity price information to convert the physical units used in process inventories to the monetary units commonly used in Input-Output models. However, prices for the same commodity can vary significantly between different supply chains, or even between various levels in the same supply chain. The resulting commodity price variance in turn leads to added uncertainty in the hybrid environmental footprint. In this paper we take international trading statistics from BACI/UN-COMTRADE to estimate the variance of commodity prices, and use these in an integrated HLCA model of the process database ecoinvent with the EE-MRIO database EXIOBASE. We show that geographical aggregation of PLCA processes is a significant driver in the price variance of their reference products. We analyse the effect of price variance on process carbon footprint intensities (CFIs) and find that the CFIs of hybridised processes show a median increase of 6–17% due to hybridisation, for two different double counting scenarios, and a median uncertainty of −2 to +4% due to price variance. Furthermore, we illustrate the effect of price variance on the carbon footprint uncertainty in a HLCA study of Swiss household consumption. Although the relative footprint increase due to hybridisation is small to moderate with 8–14% for two different double counting correction strategies, the uncertainty due to price variability of this contribution to the footprint is very high, with 95% confidence intervals of (−28, +90%) and (−23, +68%) relative to the median. The magnitude and high positive skewness of the uncertainty highlights the importance of taking price variance into account when performing hybrid LCA.