Life Cycle Assessment Calculations Research Articles

Methodology of Eco-Design and Software Development for Sustainable Product Design

In the face of the growing social recognition of environmental awareness and emerging regulations in countries where targets include the reduction of the CO2 footprint in the industrial sector, several companies are facing the challenge of introducing environmental impacts as new key design criteria. To successfully launch new products with optimized environmental impact, it is crucial to apply Life Cycle Assessment (LCA) during the design phase. However, the design process of any product is a process where materials, production processes, concepts, and various design factors are constantly changing, which requires an agile LCA calculation for its effective inclusion during the iterative design process. This paper presents an eco-design methodology, based on the adaptation of the LCA method to the changing design environment, through the adaptation of LCA stages to the design process, the customization of environmental databases to the product of the company, and the development of a software tool for its application during the earlier design phases. This methodology assists designers to save efforts during the calculation process, with different integration levels of environmental data, according to LCA phases established by ISO 14040 and ISO 14044. The effectiveness of this methodology will be shown with a real case study.

Life cycle assessment and forecasting for 30kW solar power plant using machine learning algorithms

Highly competitiveness of solar power plants in the energy market requires addressing the active research problem of solar energy forecasting. To make precise forecasts, however, historical meteorological, production, or irradiance data is insufficient. As the conservation of these Renewable Energy Sources (RES) is that much essential, the use of Photovoltaic (PV) panels have subsequently increased. The output of these PV panels completely depends on the climate. As the PV panels convert the solar energy to electrical energy, therefore, it produces the most when there is enough sunlight throughout the summer and the least when there is rain. Accurate forecasting of energy generation from solar power plants is crucial in terms of economics due to this uncertainty in the output in different seasons and the change in meteorological conditions. The objective of this paper is to investigate machine learning algorithms can accurately anticipate solar power for the upcoming hour and hourly days in advance. The Naïve Bayes Algorithm, Multilayer Perceptron Theorem (MLP), and Long Short-Term Memory networks (LSTM) are the machine learning algorithms investigated. Both historical weather data and generation data are used in the study. This study also includes the payback period (PB) and life cycle assessment calculation of the roof top solar power plant located in Bhubaneswar India.

Recent Technological Advancements in BIM and LCA Integration for Sustainable Construction: A Review

In the high-energy, high-carbon landscape of the construction industry, a detailed and precise life cycle assessment (LCA) is essential. This review examines the role of building information modeling (BIM) software in streamlining the LCA process to enhance efficiency and accuracy. Despite its potential, challenges such as software interoperability and compatibility persist, with no unified standard for choosing BIM-integrated LCA software. Besides, the review explores the capabilities and limitations of various BIM software, LCA tools, and energy consumption tools, and presents characteristics of BIM-LCA integration cases. It critically discusses BIM-LCA integration methods and data exchange techniques, including bill of quantities import, Industry Foundation Classes (IFC) import, BIM viewer usage, direct LCA calculations with BIM plugins, and LCA plugin calculations. Finally, concluding with future perspectives, the study aims to guide the development of advanced LCA tools for better integration with BIM software, addressing a vital need in sustainable construction practices.

EPiC grasshopper: A bottom-up parametric tool to quantify life cycle embodied environmental flows of buildings and infrastructure assets

Reducing the embodied environmental flows of built assets is becoming increasingly important and is a key priority for actors in the built environment to improve life cycle environmental performance. Policies and related targets for embodied environmental flow reductions are emerging. Despite this, tools for quantifying the life cycle embodied environmental flows of built assets are limited in variety and scope. Parametric life cycle assessment (LCA) tools have emerged to address some of these limitations. These tools can enhance decision making, be embedded directly into CAD programs, and offer real-time LCA calculations across multiple design variations. Yet, existing parametric tools for LCA rely on process-based material environmental flow data, limited geometries, limited real-time data visualisation capacity, and often require specialised technical expertise to use. These gaps limit their ability to provide transparent, robust, and rapid assessments. This paper introduces EPiC Grasshopper, an open-source, open-access, bottom-up, parametric tool that enables the quantification of life cycle embodied environmental flows at the early stages of built asset design, bridging the aforementioned gaps. The key characteristics and functionalities of the tool are described, followed by verification (checking that calculations are correct), validation (checking that results are representative of reality), and demonstration of its application to two built asset case studies, i.e. parametrically-defined Australian house and road. The paper shows how the tool can be used to generate designs to meet specific embodied environmental flow targets as well as streamline and increase the uptake of embodied environmental flow assessment and considerations in built asset design workflows.

A process systems engineering view of environmental impact assessment in renewable and sustainable energy production: Status and perspectives

With the increasing concern for climate change, renewable and sustainable energy production has attracted considerable attention from the scientific community, industrial practitioners, and policy and decision-makers. There are many technological alternatives for each sub-category of complex sustainable energy systems. Life cycle assessment (LCA) can be an effective tool to compare the environmental impacts of each pathway and identify the most promising alternatives from an environmental impact perspective. This contribution first reviews the environmental assessment methods and tools developed over the years. Secondly, a comprehensive review of the contribution of the PSE community to the environmental impact analysis of renewable energy systems is performed. It is observed that while LCA is the preferred method, these studies differed widely concerning the choice of impact assessment method used, the level of details shared concerning the underlying LCA calculations, and whether or not sensitivity and uncertainty analyses were carried out, among many others. This makes the comparison of results from different studies difficult and often impossible. It is clear that the PSE community, with its emphasis on systems thinking and holistic approaches, plays a critical role in the design, integration, and operation of complex sustainable energy systems. However, the thorough calculations necessary to ensure a robust and transparent LCA analysis require a shared methodology and a detailed description of the rules. Such explicit, systematic, and transparent methods will set the bar for a minimum requirement for thorough LCA calculations, ensuring fair comparison and discussions of different technical solutions developed in the wider PSE community for sustainable renewables.

Life cycle assessment of a marine biorefinery producing protein, bioactives and polymeric packaging material

Abstract Purpose Algal research has been dominated by the use of marine biomass (mainly microalgae) as feedstock in the production of second-generation biofuels, albeit with limited economic success. A promising alternative strategy is the valorisation of seaweed (macroalgae), with the cascaded extraction of its high-value components, as well as lower-value components further downstream, under the ‘biorefinery concept’. The goal of this study was to assess the environmental performance of one such marine biorefinery situated in the UK. Methods Attributional life cycle assessment (LCA) was conducted on a hypothetical marine biorefinery coproducing fucoidan, laminarin, protein and alginate/cellulose packaging material (target product), from cultivated Saccharina latissima. The functional unit was the production of 1 kg of packaging material. A total of 6 scenarios were modelled, varying in coproduct management methodology (system expansion, mass allocation or economic allocation) and applied energy mix (standard or green energy). Sensitivity analysis was also conducted, evaluating the systems response to changes in allocation methodology; product market value; biomass composition and transport mode and distance. LCA calculations were performed using OpenLCA (version 1.10.3) software, with background processes modelled using the imported Ecoinvent 3.6 database. Environmental impacts were quantified under ReCiPe methodology at the midpoint level, from the ‘Heirarchist’ (H) perspective. Results and discussion The overall global warming impacts ranged from 1.2 to 4.52 kg CO2 eq/kg biopolymer, with the application of economic allocation; 3.58 to 7.06 kg CO2eq/kg with mass allocation and 14.19 to 41.52 kg CO2eq/kg with system expansion — the lower limit representing the instance where green electricity is used and the upper where standard electricity is employed. While implementing the green energy mix resulted in a 67% reduction in global warming impacts, it also incurred a 2–9 fold increase in overall impacts in the categories of terrestrial acidification, human non-carcinogenic toxicity, land-use and terrestrial ecotoxicity. Economic allocation resulted in burden shifting most favourable to the packaging material pathway. Conclusions This study demonstrates that the road to environmental optimisation in marine biorefineries is fraught with trade-offs. From the perspective of LCA — and by extension, the eco-design process that LCA is used to inform — when evaluating such product systems, it serves to strike a balance between performance across a broad spectrum of environmental impact categories, along with having consideration for the nature of energy systems incorporated and LCA methodological elements. Graphical Abstract

Environmental burdens analysis of current music player devices through Life-Cycle Assessment methodology and optimum lifespan of these apparatus

Listening to music has unavoidable environmental impacts due to the technology used to reproduce it. The primary goal of this research is to calculate the impacts of streaming music data on the latest technological appliances, namely a smart TV (STV) and a smartphone (SPH). Furthermore, we have virtually modelled potential new sustainable scenarios, assessing their entire cradle-to-grave life cycle, through Life-Cycle Assessment (LCA) methodology, in order to understand within how many years of its lifespan an old appliance ought to be replaced with a new one for the purpose of reducing the Global Warming Potential (GWP) affections.According to the results, the selected 6.5-inch-screen smartphone emits 49.28 kg CO2-eq during its lifespan (9.00 g CO2-eq per hour), while the smart TV emits 406.40 kg CO2-eq throughout its average lifetime (32.56 g CO2-eq per hour). More specifically, the impacts associated with their use as music players are 2.58 g CO2-eq per listened hour in the case of the smartphone and 8.18 in that of the smart TV, taking music as occupying 25 % of the use phase of the SPH and 29 % of the use phase of the STV, as global averages. In the sustainable scenarios modelled, when the old appliances are replaced with new more efficient ones (Scenarios 1 and 2), GWP could be reduced by up to 8.82 % and 3.15 % for the SPH and the STV respectively. However, if old appliances are instead run on renewable energy and an efficient use of them is made (Scenarios 3 and 4), GWP could be reduced by up to 9.77 % and 60.75 %, respectively. Meanwhile, the optimum substitution lifespan for the SPH increases from 27.78 to 175.76 years, and that of the STV increases from 4.64 to 29.33 when this renewable energy and efficient use scenario is simulated.Thus, this research serves to confirm that the replacement of appliances is not justifiable as an attempt to reduce their environmental impact, unless renewable energy is used in our music reproduction appliances. Therefore, from an environmental point of view, the environmental effectiveness of substituting old appliances with new ones when listening to music is not supported by the data presented in this research. Rather, this research supports the view that the public funds should prioritise the goal of running appliances on renewable energy, rather than classic “renovation plans” or scrappage schemes of old music player appliances. The research shows how different policy-making strategies could bring numerous GWP reductions on account of the whole life cycle of these appliances, and underlines the significance of LCA calculations in determining public policy.

Investigation of the Carbon Footprint of the Textile Industry: PES- and PP-Based Products with Monte Carlo Uncertainty Analysis

The Carbon Border Adjustment Mechanism was developed to ensure that industrial sectors operating outside the EU follow the same environmental standards and targets while competing with the EU’s carbon market. This mechanism aims to calculate the carbon footprint of goods and services imported into the EU and make carbon adjustments accordingly. The transition phase, starting in 2023, represents the period when the Carbon Border Adjustment Mechanism will be implemented. The completion of the transition phase is targeted for 2025. By this date, the effective implementation of this mechanism is aimed at demonstrating that countries outside of the EU comply with emissions regulations using Carbon at Border certificates. The textile industry’s products have a significant environmental impact throughout their life cycle, from the production of raw materials to the disposal of the finished product. Textile production, especially synthetic yarns, requires large amounts of energy, contributing to greenhouse gas emissions and climate change. In this study, a “cradle-to-customer plus waste” life cycle assessment (LCA) is conducted to evaluate the environmental impacts of two products in the textile sector. The Monte Carlo analysis method can be used to handle uncertainties in LCA calculations. It is a method for modeling uncertainties and statistically evaluating results. In this study, this method is preferred at the stage of determining uncertainties. The processes from chips to yarns are investigated for two synthetic yarns: polyester (PES) and polypropylene (PP). The carbon emissions of PP and PES used in textiles are calculated for the first time in this study using detailed modeling with LCAs and a real application. The main production operations are considered: (i) transport of raw materials and packaging material, (ii) energy consumption during the production process, (iii) transport of products, and (iv) end-of-life steps. When the actual data obtained from a company are analyzed, the carbon footprints (CFs) of the PES and PP are calculated to be 13.40 t CO2-eq (t PES)-1 and 6.42 t CO2-eq (t PP)-1, respectively. These data can be used as reference points for future studies and comparisons. According to the results obtained, when the energy consumption and raw material stages in the production of the PES and PP products are compared, it is seen that the CF of PP yarn is lower, and it is more environmentally friendly. These findings can be utilized to enhance government policies aimed at reducing greenhouse gas emissions and managing synthetic yarn production in Türkiye. Since PP and PES raw materials are predominantly used in synthetic yarns, this study’s objective is to quantify the carbon emissions associated with the utilization of these raw materials and provide guidance to companies engaged in their production.

Evaluating Environmental Impacts with LCA to Achieve Carbon Neutral Societies

This study investigated the Life Cycle Assessment (LCA) of a manufacturing SME engaged in the metal processing industry. According to recent public tenders, LCA has a large influence in deciding whether to support a project. Even when the project describes only a part of the company's operations, LCA is mandatory. The impact of the advanced way of storing industrial gases and the inclusion of new technological equipment on environmental indicators was discussed. Input data was obtained from the company's management and the technical specifications of the new equipment. The LCA calculation was performed in the SimaPro software environment and in the ECOINVENT 3.8 database. The goal of this study was to show a positive impact of LCA even in the case of minor interventions by companies in their production processes, which do not include a comprehensive review of the company. The established practice of analyzing the life cycle of processes for the entire company represents, in the case of minor adaptations of processes, a non-rational treatment of factors that do not affect the improvement of environmental indicators. Carrying out more narrowly focused LCAs brings important information to the company about the rational inclusion of certain optional solutions at each production unit. In this way, the environmental aspect of the project is already included in the planning phase and does therefore not represent subsequently adopted decisions, which are taken simply to achieve the required standards in environmental areas. To help address these gaps, a sensitivity analysis is made on the influential input parameters, and their impact on the environmental parameters is shown. We compared the results before the company's investment (year x) and after the company's investment (year x1). The results show a great positive impact on the reduction of environmental indicators and confirm the applicability of LCA in companies that tend to improve them and achieve a carbon-neutral society. Doi: 10.28991/HEF-2023-04-03-05 Full Text: PDF

Coupling the digital twin technology and life cycle assessment: Carbon dioxide emissions from polysilicon production

With global warming becoming more serious, countries have begun to strengthen the regulation of carbon dioxide (CO₂) emissions, especially in high‑carbon industries such as metallurgy. This paper uses Plant Simulation v14.0 (PS) software to carry out digital twin (DT) modeling of a polysilicon factory in China. In order to study the carbon emissions in the polysilicon production process, and then integrates the calculation logic of life cycle assessment (LCA) into DT technology (DT-LCA) in order to carry out LCA of the modeled factory. As a comparison, eBalance v4.7 (eB) is applied to implement regular LCA of the modeled factory and thorough analysis of CO₂ emission during the production process. As is shown in the contributions analysis, trichlorosilane (TCS) reduction, metallurgical silicon smelting and TCS rectification account for three primary resources for the production of CO₂, with the exact percentage being 59.09 %, 11.50 % and 8.21 % respectively. The sensitivity analysis shows that the consumption sensitivity of electricity and TCS (added) rank at the top in the process of TCS reduction, with the exact numbers being 39.84 % and 18.87 % respectively. Next, the electricity consumption in the metallurgical silicon smelting process and the steam consumption in the TCS rectification process are respectively 7.72 % and 6.47 %. By LCA calculation, the production of 1 kg polysilicon results in up to 113.30 kg CO₂, while, if DT-LCA calculation is applied, 108.93 kg CO₂ is made in the same process. With a 96.14 % of matching between the two results, it has been proved that online monitoring of the total CO₂ emission during the production of polysilicon, which comprises both direct and indirect emissions, can be realized using DT-LCA emissions. This will facilitate the digitization and intelligentization of the domestic silicon industrial chain and provide data support for the establishment of carbon emission benchmark in high‑carbon industries (e.g., polysilicon industry) and promote the expansion of carbon trading market in China. Finally, based on the analysis results, suggestions for further reduction of CO₂ emission were given.

A Parametric BIM Framework to Conceptual Structural Design for Assessing the Embodied Environmental Impact

Decisions made in the early design stage have a significant effect on a building’s performance and environmental impact. In practice, a conceptual design is performed by an architect, while a structural engineer begins to work in later phases when the architectural concept has already evolved. However, the geometry and form of a building directly determine the type of structure and applicable materials; therefore, the conceptual design phase gives rise to examining alternative solutions. This paper presents a method for generating alternative structural solutions in the conceptual design phase and examining their embodied environmental impact by integrating parametric design and building information modeling (BIM). Rhinoceros and Grasshopper were used to develop the parametric script, which includes the generation of geometrical variations, the automatic definition of initial cross sections for the load-bearing elements based on in-built structural design approximations, the datasets for embodied environmental impact of the used building materials, the generation of life cycle inventory (LCI), the automatic calculation of life cycle assessment (LCA) results based on the geometry, and the conversion of the parametric model into building information model. The method was demonstrated using a case study of 48 different alternative solutions for an unheated warehouse made of steel frames. Based on the results, the areas with the greatest energy impact were identified. The case study analysis also illustrated that the applied cross section may have a significant effect on the impact categories. The results draw attention to the complexity of LCA calculations even in the case of a simple structure containing a limited number of variables, where parametric design can serve as an effective tool for a comprehensive environmental impact assessment.

An exploratory study of FA-based hybrid binder with alkaline sulfates as activator

Hybrid binders emerge as an intermediate solution to further decrease the clinker factor in cementitious systems without unfavorable slow development of microstructure. There is an amount of fly ash that is not yet used in the production of cementitious materials due to its limited reactivity. Therefore, by the election of an appropriate activator and small contents of Portland cement, it may be possible to provide an acceptable behaviour in terms of early-age strength and at the same time to achieve a valorization of these supplementary cementitious materials. This paper presents results of an exploratory study for the activation of a low calcium fly ash in hybrid systems. In literature previous studies have proved the synergy effect between GGBFS and FA in AAMs. For these reasons, low amounts of GGBFS with a lower carbon footprint than PC were also incorporated into some mixes. The interaction Portland cement/activator seems to control the early age behaviour. Life Cycle Assessment calculations for mortars are also presented. By comparing the different mixes in a cradle-to-gate oriented analysis, an estimation of the eco-efficiency of each of the systems was obtained. The results demonstrated that the addition of sodium sulfate was the most effective approach for hybrid binders containing FA and GGBFS, increasing not only the heat release but also the compressive strength.

Life cycle assessment of eco-brick production using PET particle reinforced epoxy resin composites

The process of urbanisation contributes to the growth of waste generation and causes environmental pollution. One of the most common plastic waste is polyethylene terephthalate (PET). This plastic waste is often used as mixed material in construction. The use of life-cycle assessment (LCA) is a possible tool to assess the sustainability of a product in the long term. After analysing the latest literature, it was found that the study of PET waste in building materials is one of the sustainable alternatives for waste reduction. This research contributes to the improvement of sustainability in alternative building materials through LCA. A gate-to-gate approach is adopted in this research. LCA Calculations for the production of eco-bricks were carried out in accordance with ISO 14044. GaBi software was used to identify and quantify impacts within the system boundaries. The calculations were based on the EDIP 2003 method for assessing impacts. The results show that the use of epoxy resin and PET as raw materials for eco-tiles has an impact on ozone formation (OF) of 118 m2 UES*ppm*hours, which is due to the use of epoxy resin chemicals as adhesives in the production of eco-bricks. Eco-bricks made of PET and epoxy resin have better compressive strength than other materials. The addition of epoxy resin adhesive can increase the compressive strength of the eco-bricks by 50%. Despite the advantages of using epoxy resin and PET in eco-bricks, there are many uncertainties about their environmental impact. It can be concluded that the use of epoxy resin and PET particles in the production of eco-bricks does not pose excessive environmental risks and their use as alternative mixtures for the production of eco-bricks does not lead to a significant reduction in the environmental profile.

Effect of Recycling on the Environmental Impact of a High-Efficiency Photovoltaic Module Combining Space-Grade Solar Cells and Optical Micro-Tracking

This paper presents a life cycle assessment (LCA) analysis of a new, high-concentration photovoltaic (HCPV) technology developed as part of the HIPERION project of hybrid photovoltaics for efficiency record using an integrated optical technology. In the LCA calculations, the production stage of a full module was adopted as a functional unit. SimaPro version 9.00.49, the recent Ecoinvent database (3.8), and the IPCC 2021 GWP 100a environmental model were applied to perform the calculations. The environmental impact of the HCPV panel was determined for constructional data and for recycling of the main elements of the module. The results of the calculations show that recycling of PMMA, rubber, and electronic elements reduced the total carbon footprint by 17%, from 240 to 201 kg CO2-eq. The biggest environmental load was generated by the PV cells: 99.9 kg CO2eq., which corresponds to 49.8% (41.7% without recycling) of the total environmental load due to the large number of solar cells used in the construction. The emission of CO2 over a 25-year lifespan was determined from 17.1 to 23.4 g CO2-eq/kWh (20.4 to 27.9 without recycling), depending on the location. The energy payback time (EPBT) for the analyzed module is 0.87 and 1.19 years, depending on the location and the related insolation factors (Madrid: 470 kWh/m2, Lyon: 344 kWh/m2). The results of the calculations proved that the application of recycling and recovery methods for solar cells can improve the sustainability of the photovoltaic industry.

Analysis Of Hazardous Medical Waste In Dr. Soehadi Prijonegoro Hospital Using A Life Cycle Assessment Approach

Hospitals are health services that produce waste and sources of pollution for human health and the environment. dr. Soehadi Prijonegoro Hospital produces the most medical waste in the sragen regency and still needs cold storage. This research evaluated the management of hazardous toxicity material medical, solid waste. Life cycle assessment calculations can be performed using a software application, simparo 9.0. This scope of research with gate to gate approach. Inventory data was obtained from primary and secondary data collection. Daily medical waste is about 135 kg, while the average month is 3961 kg—medical waste management in dr. Soehadi Prijonegoro includes reducing, sorting, labeling, storage, transporting, and processing have been following applicable regulations. The results of the TCLP test of solids incinerator ash and chimney incinerator emissions meet the quality standards. The most significant impact on the ecosystem is the global warming potential in the emergency service room. For impacts, the natural resources and the impact on the ecosystem is the inpatient room due to excessive use of medical waste. Use of energy and materials to minimize emissions and waste. Keywords: Hospital, Waste, Impact

Feasibility of Planting Trees around Buildings as a Nature-Based Solution of Carbon Sequestration—An LCA Approach Using Two Case Studies

In response to Canada’s commitment to reducing greenhouse gas emissions and to making pathways to achieve carbon neutral buildings, this paper presents two real case studies. The paper first outlines the potential of trees to absorb CO2 emissions through photosynthesis, and the methods used for the estimation of their annual carbon sequestration rates. The net annual carbon sequestration rate of 0.575 kgCO2eq/m2 of tree cover area is considered in our study. Then, this paper presents the carbon life cycle assessment of an all-electric laboratory at Concordia University and of a single-detached house, both located in Montreal. The life cycle assessment (LCA) calculations were performed using two software tools, One Click LCA and Athena Impact Estimator for Buildings. The results in terms of Global Warming Potential (GWP) over 60 years for the laboratory were found to be 83,521 kgCO2eq using One Click LCA, and 82,666 kgCO2eq using Athena. For the single-detached house that uses natural gas for space heating and domestic hot water, the GWP was found to be 544,907 kgCO2eq using One Click LCA, and 566,856 kgCO2eq using Athena. For the all-electric laboratory, a garden fully covered with representative urban trees could offset around 17% of the total life cycle carbon emissions. For the natural gas-powered single-detached house, the sequestration by trees is around 3% of the total life cycle carbon emission. This paper presents limits for achieving carbon neutral buildings when only the emissions sequestration by trees is applied, and discusses the main findings regarding LCA calculations under different scenarios.

Applying life cycle assessment with minimal information to support early-stage material selection

Traditional life cycle assessment (LCA) is too data intensive and time consuming to be used during typical building design processes. Conducting an LCA during the building design process therefore requires simplifications and assumptions. Such “screening LCAs” are quicker and can be used with less data but introduce greater uncertainty. Unfortunately, uncertainty is not reflected in standard deterministic LCA calculations, which produce single-point values in LCA results. Thus, in this study, data quality scoring has been incorporated into a screening LCA to produce probabilistic predictions of environmental performance based on limited data. The approach has been applied during the design process of a bio-based wall panel designed for a circular economy. A combination of ecoinvent and material data sheets were used to analyse a wide range of novel bio-based insulation materials. The screening LCA analysed global warming potential and identified a short-list of promising materials that were then subjected to a detailed LCA for further consideration in the design. The method uses publicly available information and can be applied at material or building-element level. The method thus helps designers estimate environmental impacts without hindering the design process.

Lifespan prediction of existing building typologies

Life-cycle assessment (LCA) is currently one of the construction industry's most widely used methods of environmental assessment. Because LCA calculations is based on life-cycle thinking are the lifespan of the building a sensitive parameter in relation to the calculated overall environmental impact of the building. More accurate assessments of the lifespans of buildings are therefore a prerequisite for reducing errors and uncertainties in LCA and Life Cycle Costing (LCC) calculations. This study evaluates a generalized logistic lifespan prediction model for existing building typologies. The model is tested as part of a Danish case study based on building data collected from 124,096 cases of demolition. The objective is to investigate whether the typical lifespan used in LCA or LCC calculations accurately describes the remaining service life of existing buildings based on different building typologies and construction periods. The study show that office buildings generally have much shorter expected lifespans than previously assumed and that multi-family housing has nearly twice the lifespan of single-family housing. The results show a tendency for a declining lifespan based on the construction period, in which newer buildings, i.e. those that are no more than thirty years old, have a lifespan that is much shorter than the average lifespan for all construction periods. These results are highly relevant for both LCA and LCC calculations of buildings since they indicate that newer buildings in northern Europe have a lower lifespan than previous studies have shown.

Performance evaluation of desulfurization and environmental impact of using waste from mines as adsorbent

This study aims to reduce the environmental impact of impurity adsorption systems on hydrogen production. Biomass is a carbon-neutral hydrogen fuel with a low environmental impact. However, during the production of biomass-derived hydrogen (biohydrogen), the hydrogen sulfide contained in the gasified biomass reduces the performance of fuel cells when hydrogen is used. Generally, hydrogen sulfide (H 2 S) is removed via impurity adsorption. However, common adsorbents such as metal oxides have a significant environmental impact. Therefore, adsorbents with lower environmental impacts are required. Thus, to improve metal depletion from the circular economy perspective, this study proposes using neutralized sediment, a waste product from the mining wastewater treatment, as an H 2 S adsorbent. In this study, we discuss the environmental impact of H 2 S adsorption systems that use neutralized sediments as adsorbents. Although the use of waste materials has a small environmental impact, it is necessary to consider the environmental impact of the inputs and outputs related to waste material generation based on life cycle assessment (LCA). Because fossil fuel-generated electricity and chemical neutralizers are input in mine wastewater treatment, the use of neutralized sediment may have a large environmental impact than the use of metal oxides from the viewpoint of LCA. Therefore, we quantitatively evaluated the environmental impact of neutralized sediment using LCA and investigated whether the environmental impact of using neutralized sediment is less than that of using metal oxides. In addition, it is not appropriate to include the production stage in the system boundary to meet the LCA standards because mineral water treatment, which is the production stage of neutralized sediment, is conducted whether neutralized sediment is utilized or not as an H 2 S adsorbent. Therefore, an LCA that does not include the production stage was also conducted to indicate the environmental benefit of waste utilization according to the actual situation. The amount of neutralized sediment used, which is calculated by the sulfur capture capacity, is necessary for the LCA calculation. However, the sulfur capture capacity of neutralized sediment has never been investigated. Hence, dynamic adsorption tests were conducted during gasification at low (40–120 °C) and high (200–300 °C) temperatures to investigate the sulfur capture capacity of the neutralized sediment in each temperature range. The results showed that the sulfur capture capacity of the neutralized precipitates was 2.28 (at 40 °C) and 5.73 (at 300 °C) g S/100 g sorbent. The results of the LCA, with and without including the neutralized sediment production process, based on the sulfur capture capacity, demonstrated that the use of neutralized sediment as an adsorbent improved the global warming potential (GWP) by 75.1% and 98.9%, respectively, compared with the use of metal oxides. In other words, this study quantitatively indicated that the use of neutralized sediment as H 2 S adsorbents has a smaller environmental impact than existing adsorbents and shows the importance of considering the actual situation in LCA for waste utilization.

Dynamic life cycle assessment for water treatment implications

Long-term impact tracking of urban water services is an important scientific basis for the sustainable development goals of future foreground systems. This study developed a dynamic life cycle assessment (DLCA) method that considers temporal variation and the resulting impacts to address the challenges of water treatment facilities based on the principles of life cycle assessment (LCA) and system dynamics (SD) models. The model was then demonstrated and validated for a water treatment facility in the Kinmen Islands, Taiwan. The SD model simulates long-term water demand in terms of growth in the domestic, agriculture, livestock, and manufacturing sectors, which provides specific inventory data for LCA calculations, with the aim of showing the impact change for future water treatment scenarios. The results showed that using imported water and reclaimed water reduced Kinmen's reliance on groundwater from 77 % to 43 % and reduced the vulnerability of urban water services. The environmental impact of water treatment plants is determined to be strongly related to the efficiency of water treatment. In the long run, wastewater treatment plants can reduce their impacts with an increase in efficiency (3.7 % impact reduction). Additionally, the development of reclaimed water technology and water savings can reduce the impact by 19 % and 13.7 %, respectively, compared to the implementation of desalination. In terms of energy policy, more profound energy savings were observed when energy saving and structure transformation were simultaneously carried out. On the other hand, desalination poses the most political risk and has energy-associated environmental impacts. The DLCA results from this study showcase the trend of impact variation over time and thus provide valuable insights for future policy-making in mapping out the benefits and priorities of policy promotion.