Absolute Environmental Sustainability Research Articles

Enabling comprehensive assessment of marine eutrophication impacts and their evaluation against regional safe operating space

Abstract Purpose Nitrogen emissions from human activities are contributing to elevated levels of eutrophication in coastal ecosystems. Mechanisms involved in marine eutrophication show strong geographical variation. Existing life cycle impact assessment (LCIA) and absolute environmental sustainability assessment (AESA) methods for marine eutrophication do not adequately represent this variability, do not have a full global coverage, and suffer from other limitations, such as poor estimation of coastal residence times. This study aims to advance LCIA and AESA for marine eutrophication. Methods We aligned and combined recent advancements in marine eutrophication LCIA and AESA methods into one method. By re-running models underlying the combined methods and incorporating additional data sources, we included marine regions missing in previous methods and improved fate modeling, with the inclusion of denitrification and plant uptake in the air emission-terrestrial deposition pathway. To demonstrate and validate our method, we applied it in a case study. Results The developed method allows the assessment of marine eutrophication impacts from emissions to soil, freshwater, and air at high resolution (0.083° and 2° × 2.5° for inland and air emissions, respectively) and spatial coverage (all ice-free global continents). In the case study, we demonstrate the added value of our method by showing that the now quantified spatial variability within spatial units, e.g., river basins, can be large and have a strong influence on the modeled marine eutrophication from the case study. Compared to existing methods, our method identifies larger occupations of safe operating space for marine eutrophication, mainly due to the high resolution of the coastal compartment, reflecting a more realistic areal extent of marine eutrophication impacts. Conclusions Although limited by factors such as simulations based on a single reference year for modeling inland and air fate, our method is readily applicable to assess the marine eutrophication impact of nitrogen emitted to any environmental compartment and relate it to the safe operating space. With substantial advancement of existing approaches, our method improves the basis for decision-making for managing nitrogen and reducing emissions to levels within the safe operating space.

Towards a unified absolute environmental sustainability decoupling indicator

AbstractManufacturing firms are facing the critical need to manage their business growth while staying within the biophysical limits of the planet. Absolute environmental sustainability decoupling (AESD) combines these goals and is one of the keys for manufacturing firms to achieve their sustainable transition. This study offers an initial contribution to categorise decoupling at the firm level while incorporating absolute environmental sustainability goals. It also explores the role of design in achieving AESD and opens doors for further research on manufacturing firms' sustainability transition.

Embedded but overlooked values: Ethical aspects of absolute environmental sustainability assessments

AbstractCurrently used sharing principles (grandfathering and final consumption expenditure) do not align with the purpose of Absolute Environmental Sustainability Assessments (AESAs)—enabling all to meet basic needs within the planetary limits. This discrepancy, though niche within life cycle engineering, demands attention due to the integration of the sharing principles in the widely adopted Science Based Targets initiative, embraced by 4000+ companies, representing over a third of the global economy. This paper suggests operationalizing sufficientarianism as a fair sharing principle for AESAs guaranteeing a minimum threshold of well‐being for all. The theory of human needs is highlighted to distinguish luxuries from necessities. This is vital when assigning shares to products/companies, as there's no room for luxuries (products for someone which cause others to fall short), given the extremely limited individual safe operating space, regardless of the sharing approach. This paper argues that sufficientarian‐based sharing principles must overlook historically skewed material welfare distributions to ensure no one falls below the minimum threshold. It underscores the need for an interdisciplinary approach to sharing principles, acknowledging and discussing diverse value perspectives on equal grounds. The focus is to inform and discuss the development of new sharing principles, which introduces initial steps toward a sufficientarian‐based approach. The paper concludes that recognizing embedded values is paramount in sharing principle development. Failing to do so risks letting quantifiable metrics dictate the values integrated into AESAs without open discourse.

A stepwise approach for determining absolute environmental sustainability targets for an electric vehicle battery

The transition from the ‘Holocene-like’ interglacial state towards the Anthropocene epoch, driven by human activities, poses risks of triggering tipping points of the Earth system. Such risks create the need for target-based product design strategies, that are aligned with the environmental carrying capacities, such as the planetary boundaries framework. In this study, we introduce a stepwise approach to determine absolute environmental sustainability targets during the product development process. The approach integrates top-down factors such as planetary boundaries, IPCC carbon budgets and sharing principles shaping these targets. Furthermore, we assess the influence of bottom-up factors such as the selection of raw material suppliers and production location in achieving them. The application of the approach is illustrated for the case study of a traction battery. The potential future applications and limitations of the proposed stepwise approach are discussed.Electric vehicle; Sustainable development; Absolute sustainability

Evaluating the Environmental Sustainability of Alternative Ways to Produce Benzene, Toluene, and Xylene.

The petrochemical industry can reduce its environmental impacts by moving from fossil resources to alternative carbon feedstocks. Biomass and plastic waste-based production pathways have recently been developed for benzene, toluene, and xylene (BTX). This study evaluates the environmental impacts of these novel BTX pathways at a commercial and future (2050) scale, combining traditional life cycle assessment with absolute environmental sustainability assessment using the planetary boundary concept. We show that plastic waste-based BTX has lower environmental impacts than fossil BTX, including a 12% decrease in greenhouse gas (GHG) emissions. Biomass-based BTX shows greater GHG emission reductions (42%), but it causes increased freshwater consumption and eutrophication. Toward 2050, GHG emission reductions become 75 and 107% for plastic waste and biobased production, respectively, compared to current fossil-BTX production. When comparing alternative uses of plastic waste, BTX production has larger climate benefits than waste incineration with energy recovery with a GHG benefit of 1.1 kg CO2-equiv/kg plastic waste. For biomass (glycerol)-based BTX production, other uses of glycerol are favorable over BTX production. While alternative BTX production pathways can decrease environmental impacts, they still transgress multiple planetary boundaries. Further impact reduction efforts are thus required, such as using other types of (waste) biomass, increasing carbon recycling, and abatement of end-of-life emissions.

A Consumption‐Based Integrated Framework for Subnational Absolute Environmental Sustainability Management

AbstractAs human consumption expands, four environmental footprints (EFs) exceed the planetary boundaries (PBs) at the global scale. Managing absolute environmental sustainability (AES) based on PBs and EFs at the subnational level is crucial for policy insights. However, a consumption‐based AES management framework still needs to be developed. A framework, including five nexus environmental pressures embodied in the supply chain, was developed and tested in our study across China's 30 provinces to address this knowledge gap. The framework involved three steps: (a) assessing AES for five environmental pressures, (b) measuring environmental surplus and overshoot and composition of EFs, and (c) identifying priority areas for AES management. The results showed that only some provinces are sustainable for three impact‐oriented indicators, especially those with larger populations. Moreover, the embodied environmental pressure mainly flows from the Northwest to Southeast China. For two resource‐oriented indicators, over 74% of provinces are absolutely sustainable. From a nexus perspective, Shandong and Shanghai are identified as priorities for AES management due to their low IESI values of 0.32, 0.33, and 0.40, respectively, which means the worst performance. To improve their IESI, Shanghai needs to control the consumption of blue water‐intensive products, while Shandong and Henan should consume fewer CO2 emissions and N‐ and P‐loss‐intensive products. This framework can clarify subnational responsibilities of environmental overshoots, guide sustainable development, and be widely used at the subnational level in countries worldwide.

An absolute environmental sustainability assessment of food

AbstractThe food sector is a major user of land and freshwater and a source of considerable greenhouse gas (GHG) emissions. This puts pressure on Earth systems and jeopardizes the future of food production. The environmental impact of foods is well understood, but our interpretation lacks the context to judge whether those impacts are sufficiently small to describe a food as environmentally sustainable or not. In this work, we describe a metric that converts the environmental impact of foods into a quantitative environmental sustainability scale (performance‐weighted environmental sustainability, PwES). Land use, freshwater use, and GHG emission impacts of common foods have been weighted by their nutritional content and normalized so that values greater than 100% are considered unsustainable. Our findings concur with the conventional wisdom that the high impact of meat is unsustainable, whereas vegetables are typically produced sustainably. Further to this, the PwES metric was used to establish rational targets for sustainable food supply and design nutritious and environmentally sustainable meal plans. It was found that without reductions to the environmental impact of food, it is very difficult to eat sustainably. A high‐bread vegan diet could be found that provided minimum nutritional requirements and was environmentally sustainable.

Are Existing LCIA Methods Related to Mineral and Metal Resources Relevant for an AESA Approach Applied to the Building Sector? Case Study on the Construction of New Buildings in France

Considering the challenges that mineral and metallic resources represent for the building sector, there is a need to propose decision-support tools to building stakeholders. One of the possibilities could be to integrate an indicator of pressure on mineral resources in an absolute environmental sustainability assessment (AESA) approach, using life cycle impact assessment (LCIA) methods. This paper will analyze the existing LCIA indicators that can be used to represent the impact on mineral resources of new constructions, with a case study on new buildings in France in 2015. This analysis aims to find out whether the existing LCIA methods dealing with mineral and metallic resources issues are adapted to the specific stakes of the building sector in an AESA approach. The AESA approach considered is the one proposed by Bjørn and Hauschild. Several steps are detailed in this paper. Firstly, bibliographic research was carried out to identify existing LCIA methods related to the mineral resources. Secondly, selection criteria were defined in order to select those LCIA methods relevant for the building sector. Thirdly, the scope of the case study was defined and its inventory analysis was conducted using the Ecoinvent 3.5 database, selecting only the mineral and metallic input flows. Finally, the comparison between the inventory of mineral and metallic flows issued from the inventory analysis and the substances considered in the selected LCIA methods was effected. The results show that none of the existing LCIA methods are compatible with the aim of developing an LCIA indicator for mineral and metallic resources that is compatible with an AESA approach, in particular for the building sector.

Ten questions concerning absolute sustainability in the built environment

Concepts for setting carrying capacity-based benchmarking of life-cycle environmental impacts is an ongoing field of research with an emerging industrial uptake in the built environment. This paper is a critical review of this development compiled in the form of 10 questions that discusses issues and challenges related to definitions, methodology, terminology, and uncertainties. The intention is not to discourage the development but to highlight the need for ensuring consensus and alignment on the aforementioned issues both within the research community and when implementing concepts in practice.Concluding that AESA (Absolute Environmental Sustainability Assessment) aims to address the environmental performance of a service, benchmarked against a functional pollution space, using environmental carrying capacities, rather than comparing it to current ‘best practice'. It is crucial to recognize that these carrying capacities are limits, not targets, and whilst allocation of the carrying capacity to services depends on subjective and political decision-making, uncertainties, including subjectivity and emerging scientific data, should be included and communicated clearly in credible AESAs.Collaboration between academia and industry is crucial to align definitions and terminology and avoid misalignments. While AESA lacks a scalable approach for systemic assessments, it serves as a valuable steppingstone for transition, highlighting that achieving a built environment within the currently known functional pollution spaces, requires policy changes and a cultural shift.

Challenges and missing links to assess absolute environmental sustainability

The results of the most prevalent environmental lifecycle assessments represent the relative impact on the environment caused by the object being assessed. Hereby, the object is compared to its alternatives (to derive: Which is the better solution?) rather than to the carrying capacities of nature (to determine: Is it ultimately sustainable or not?). This poses a problem for implementing and assessing the progress towards sustainable development. In connection to this, prior research has started categorizing the constitutive research on lifecycle-based absolute environmental sustainability assessments.This paper adds to these efforts and provides a new point of view by categorizing the absolute environmental sustainability assessment approaches within the driver-pressure-state-impact-response framework. Hereby, we focus on the absolute environmental sustainability assessment approaches of (1.) the precedent methods of absolute pressures, and (2.) the state-of-the-art approaches of the impacts on nature. Their common challenges and limitations are discussed, along with a theoretical example. From there, we conclude the proposal of incorporating the absolute environmental sustainability pressure methods into the current discussion on lifecycle-based absolute environmental sustainability assessment approaches. Ultimately, we conclude that further research is required to connect the approaches to the level of application.

Quantifying pesticide emissions for drift deposition in comparative risk and impact assessment

Estimating emissions of chemical pesticides used in agriculture is an essential component in evaluating the potential toxicity-related impacts on humans and ecosystems in various comparative risk and impact assessment frameworks, such as life cycle assessment, environmental footprinting, absolute environmental sustainability assessment, chemical substitution, and risk prioritization. Emissions related to drift deposition—usually derived from drift experiments—can reach non-target areas, and vary as a function of crop characteristics and application technique. We derive cumulative drift deposition fractions for a wide range of experimental drift functions for use in comparative and mass-balanced approaches. We clarify that cumulative drift deposition fractions require to integrate the underlying drift functions over the relevant deposition area and to correct for the ratio of deposition area to treated field area to arrive at overall mass deposited per unit mass of applied pesticide. Our results show that for most crops, drift deposition fractions from pesticide application are below 0.03 (i.e. 3% of applied mass), except for grapes and fruit trees, where drift fractions can reach 5% when using canon or air blast sprayers. Notably, aerial applications on soybeans can result in significantly higher drift deposition fractions, ranging from 20% to 60%. Additionally, varying the nozzle position can lead to a factor of five differences in pesticide deposition, and establishing buffer zones can effectively reduce drift deposition. To address remaining limitations in deriving cumulative drift deposition fractions, we discuss possible alternative modelling approaches. Our proposed approach can be implemented in different quantitative and comparative assessment frameworks that require emission estimates of agricultural pesticides, in support of reducing chemical pollution and related impacts on human health and the environment.

Automating relative and absolute environmental sustainability assessments of bio-based products

Awareness of long-term environmental challenges has motivated society toward a more sustainable future. Biotechnology is expected to contribute to the transition towards sustainability. Automation can play an important role in this transition, enabling faster decision-making at early stages. Therefore, an automated relative and absolute environmental sustainability assessment is presented to boost innovation in biotechnology. The automated calculation methodology uses computer-aided tools (dedicated software and Python codes) for the fast quantification of the environmental sustainability performance of bio-based products including scenario and uncertainty analysis. Two case studies (i) succinic acid (SA) and (ii) poly-lactic acid (PLA) are evaluated to test the capabilities of the automated assessment. The results show a carbon footprint and land use of 5.46 kg CO2 eq and 1.26 m2a crop eq for SA and 3.82 kg CO2 eq and 0.74 m2a crop eq for PLA. Transgression of planetary boundaries was found in both SA and PLA production.

Spatially-explicit absolute life cycle assessment by multi-regional hybrid modeling: Computational framework

Human activities, environmental impacts, and the provision of ecosystem services vary by region. The existing regional environmental sustainability assessment approaches addressed such regional heterogeneity of inventory data at a single scale (i.e., either process or economy scale). However, depending on regional data availability and the assessment scope, a multiscale modeling approach that integrates existing data and models at various scales needs to be employed. This work introduces a general computational framework for spatially-explicit environmental sustainability assessment based on a multi-regional hybrid modeling approach. The developed framework accounts for regional activities at multiple scales by integrating the existing regional approaches at each scale. Also, the framework integrates the supply of ecosystem services, which vary by region as well, at multiple scales to perform spatially-explicit absolute environmental sustainability assessment. The proposed framework is demonstrated using an illustrative example of corn production in two regions. The results are discussed in comparison to the conventional approaches.

Urea production: An absolute environmental sustainability assessment

The demand for urea, as the most popular global nitrogen fertilizer, is on the rise and as such, its performance in an environmentally sustainable perspective relative to planetary boundaries is high on the agenda. The increasing interest in nitrogen fertilizers is to improve agricultural methods for a better production rate, but can it become environmentally sustainable? Which is due to the significant contribution of fertilizers in the anthropogenic impacts of industrial activities on nature, should be considered. Here, a system analysis based on real data using life cycle assessment linked to the planetary boundaries framework (PB-LCIA) was conducted to study the performance of total urea consumption in Iran, 1.8E+6 metric tons per year. In LCA, midpoint and endpoint methods (ReCiPe 2016) and for AESA, a PB-LCIA methodology was utilized. Results showed that global warming potential, freshwater eutrophication, and marine eutrophication contribute 1.37E+09 kg CO2 eq, 1.63E+04 kg P eq, and 1.28E+04 kg N eq, respectively, while the GHG emissions of combustion, electricity, and natural gas sweetening have the most contribution to global warming by 35, 24 & 15 %, respectively. Regarding absolute sustainability, global warming, ocean acidification, and biochemical N exceed this activity's assigned share of safe operating space (SoSOS). However, choosing different sharing principles can influence to what extent this activity exceeds or stays within the assigned SoSOS; accordingly, the Nitrogen Biogeochemical flows depend on the sharing principle. Ultimately, the total Iranian urea consumption as fertilizer is not absolutely sustainable. The promising point is that producing sustainable electricity and feedstocks could lead to more sustainable urea fertilizers.

Evaluating source separation wastewater systems using traditional life cycle assessment and the planetary boundaries approach

Life cycle assessment (LCA) is a commonly used method for assessing environmental impacts of systems, but cannot produce absolute values, i.e. a comparison with existing calculated values, which represents limits of what can be emitted into the environment. Therefore, absolute environmental sustainability assessments have been developed to assess impacts against the planetary boundaries (PBs) of the safe operating space for humanity. Since PB-LCAs are novel, it is useful to analyze both results from this method and conventional LCAs, something which has not been done before. This study applied both methods to two full-scale sanitation systems in the city of Helsingborg, Sweden. The current conventional system for handling wastewater with active sludge and food waste to biogas production was compared with the novel project H+ source separation system with three pipes (food waste, grey and black water) with increased resource recovery through anaerobic digestion, ammonia stripping, struvite precipitation and pelletization. The Planetary Boundaries LCA (PB-LCA) results showed that both systems exceeded eight of the assigned shares of PBs, including climate change and biogeochemical flows of nutrients. Traditional LCA (ReCiPe impact assessment) showed net savings for the H+ system in a few categories and considerable reductions in several impacts, e.g., global warming potential (GWP), stratospheric ozone depletion, terrestrial acidification, and water consumption. In PB-LCA the H+ system gave additional impacts in both assessments for a few categories, mostly due to high consumption of chemicals in the ammonium stripping process used for nutrient recovery. In conclusion, the combined assessments highlight hot-spots for process optimization in the H+ system. From a methodological standpoint, PB-LCA still needs improvements to better reflect avoided burdens and results from traditional LCA should be fully transparent and analyzed carefully. The assessment methods complement each other and can be combined to better represent environmental performances of systems.

Integrating Absolute Sustainability and Social Sustainability in the Digital Product Passport to Promote Industry 5.0

The establishment of the digital product passport is regarded to be a prominent tool to promote environmental and social sustainability, thus enabling the transition towards Industry 5.0. In this way, it represents a holistic tool for the decision-making process of several actors of a product’s value chain. However, its development is still ongoing and the absolute perspective of environmental sustainability and the social sustainability have been overlooked. The present work aims to fill these gaps and complement the literature currently available on the digital product passport with a threefold purpose. Firstly, by referring to social life cycle assessment methodologies, useful social indicators to include in the digital product passport are discussed and proposed. Secondly, the need for an absolute perspective of environmental sustainability that respects the natural limits of our planet is presented; based on the LCA methodology and the Planetary Boundaries framework, environmental attributes and environmental impact indicators with the corresponding threshold are proposed to be included in the passport and enable the so-called absolute environmental sustainability assessment of products. Finally, a framework based on a cyber-physical system for filling in the digital product passport throughout a product lifecycle is conceived. This work represents an example of how the hallmark technologies of Industry 4.0 can be used towards Industry 5.0.

Evaluation of life cycle impacts of European electricity generation in relation to the Planetary Boundaries

The Planetary Boundaries framework was developed to control the anthropogenic pressure on the Earth system and delimit a safe operating space for humanity. Within the European Union (EU), the energy sector is the most emitting sector. Many studies have investigated life cycle impacts of electricity generation, but assessments of the life cycle impacts of electricity generation in relation to the planetary boundaries are currently limited. Here, we evaluate the life cycle impacts of electricity generation in the EU-28 and relate these impacts to the planetary boundaries. Moreover, we include an assessment of impacts on the planetary boundary biosphere integrity, which has often been omitted due to its complexity and inadequate basis for quantification. Three scenarios (Base, Green, and NZE) for the period 2020–2050 are considered, and two different sharing principles are applied for assigning a share of the safe operating space to the considered system. We found that neither of the three scenarios can be considered within the boundaries of the assigned safe operating space using either of the sharing principles. All three scenarios comply with an equal number of boundaries defined by SoSOS 1 in year 2050 (7 out of 15 boundaries), but in relation to the boundaries defined by SoSOS 2 the Green scenario performs best, complying with 13 out of 15 boundaries. The good performance of the Green scenario in 2050 is especially due to the large share of renewable energy sources (74 %) and nuclear (21 %), and because of the inclusion of BECCS, giving negative impacts on climate change. The results of the study indicate a need for a drastic change in the electricity mix of the EU-28 towards a larger share of renewable energies and emphasize the importance of considering all planetary boundaries to avoid burden shifting and to obtain absolute environmental sustainability for EU-28 electricity generation.

Absolute environmental sustainability assessment of rice in Pakistan using a planetary boundary-based approach

The increasing anthropogenic pressure with high food demands requires fundamental changes in global food production practices while respecting the environmental and resource limits of the Earth. Half of the world population consume rice as a staple food which is grown in more than a hundred countries. This study aimed at evaluating the environmental repercussions of rice production in Pakistan following a novel approach. The adopted methodology, planetary boundary-based life cycle assessment, enabled the evaluation of the sustainable limits while respecting the carrying capacity of the Earth. The results revealed that the rice production had considerable impacts in terms of global warming (5632 ± 17.8 % kg CO2 eq), freshwater eutrophication (0.67 ± 43.5 % kg P eq), and water use (3928 ± 12.7 % m3) per tonne of milled rice; contributing to the triple planetary crisis, viz., global warming and nutrient pollution as well as unsustainable use of valuable resources. Field emissions due to microbial activity of methanogenic bacteria, fossil-based irrigation processes, and agrochemical applications were identified as the hotspots. Sensitivity analysis revealed that yield increment could be a beneficial approach to reduce environmental burdens; particularly where the impacts were surpassing the sustainable limits. Furthermore, sensitivity and uncertainty analyses also confirmed the obtained results for most of the impact categories (global warming, freshwater eutrophication, and water use) were significantly higher than the considered sustainable limits. Environmentally friendly irrigation systems, improved fertilizer use efficiency, and short-duration rice varieties with higher yield were recommended due to the substantial impacts reduction potential.

A new consistent framework for assignment of safe operating space to B2C and B2B industries for use in absolute environmental sustainability assessments

The planetary boundaries define a safe operating space for humanity to act within without potentially destabilizing the planet. The safe operating space is often used a sustainability reference in Absolute Environmental Sustainability Assessments (AESAs) where a share of the safe operating space (SoSOS) is assigned to the assessed activity. An identified challenge is that current methods are suited for business-to-consumer (B2C) industries and companies, but ill-suited for assessments of business-to-business (B2B) as the sharing is often based on the direct value to humans. Thus, this study presents a systematic framework for assigning a SoSOS to both B2C and B2B industries and companies. The framework uses multi-region input-output models to link industries and to estimate the direct and indirect value to humans for both B2B and B2C industries. The framework was tested in a case study for a B2B company to show its application and to evaluate the sensitivity of the framework towards different modelling choices. The results of the case study and sensitivity analyses were used to provide recommendations for further improvement of the framework. While there is still need for improvement and refinement, the framework shows large potential. Mainly because it directly facilitates AESA of B2B industries and companies, in order to help gauging their environmental performance relative to absolute boundaries and, thus, provide better basis supporting strategic sustainability related activities.

Environmental Sustainability Assessment of Hydrogen from Waste Polymers.

The rising demand for single-use polymers calls for alternative waste treatment pathways to ensure a circular economy. Here, we explore hydrogen production from waste polymer gasification (wPG) to reduce the environmental impacts of plastic incineration and landfilling while generating a valuable product. We assess the carbon footprint of 13 H2 production routes and their environmental sustainability relative to the planetary boundaries (PBs) defined for seven Earth-system processes, covering H2 from waste polymers (wP; polyethylene, polypropylene, and polystyrene), and a set of benchmark technologies including H2 from natural gas, biomass, and water splitting. Our results show that wPG coupled with carbon capture and storage (CCS) could reduce the climate change impact of fossil-based and most electrolytic routes. Moreover, due to the high price of wP, wPG would be more expensive than its fossil- and biomass-based analogs but cheaper than the electrolytic routes. The absolute environmental sustainability assessment (AESA) revealed that all pathways would transgress at least one downscaled PB, yet a portfolio was identified where the current global H2 demand could be met without transgressing any of the studied PBs, which indicates that H2 from plastics could play a role until chemical recycling technologies reach a sufficient maturity level.