Taking into account water use impacts in the LCA of biofuels: an Argentinean case study

Purpose  

The assessment of biofuels has until now mainly focused on energy demand and greenhouse gas emissions. Only little attention has been given to other impacts, although the general importance of water use for the life cycle assessment (LCA) of agricultural products has been recognized in recent publications. The aim of this work is to assess in detail the water consumption along a biofuel production chain taking into account irrigation efficiencies, levels of water scarcity, and type of feedstock, and to integrate those results in a full LCA. Furthermore, we compare the results for biofuels from various feedstocks and regions with conventional petrol.     

Correlation analysis of life cycle impact assessment indicators measuring resource use

Introduction  

Even though the necessity of a sustainable use of natural resources is widely accepted, there is neither consensus on how “resource use” is clearly defined nor how it should be measured. Depending on the definition, it can comprise raw material consumption only or the consumption and pollution of natural resources. Consequently, lots of indicators can be applied, and the result of a life cycle assessment study aiming to quantify resource use seems to depend on the selection of impact categories. Therefore, this paper aims at analyzing life cycle impact assessment results obtained by means of several indicators to check if different indexes lead to similar results and if the number of indicators can be reduced.     

LCA of the timber sector in Ghana: preliminary life cycle impact assessment (LCIA)

Purpose  

Most life cycle impact assessment (LCIA) approaches in life cycle assessment (LCA) are developed for western countries. Their LCIA approaches and characterization methodologies for different impact categories may not be necessarily relevant to African environmental conditions and particularly not for the timber sector in Ghana. This study reviews the relevance of existing impact categories and LCIA approaches, and uses the most relevant for the timber sector of Ghana.     

The influence of contaminants in the environmental impact of recovered paper: a life cycle assessment perspective

Purpose

This study aims to analyze and quantify the environmental impacts associated with the production of testliner paper using 100?% recovered paper as fiber raw material, by applying the life cycle assessment principles. A simulation of advanced sorting technology was done to prepare and use batches of raw materials with different levels of contaminants. Comparative studies of environmental impact assessment were focused on the quality of recovered paper, which is decisively influenced by the efficiency of the sorting process. The particularity of the study is that so far it is the only one that analyzes the environmental impact generated by recovered paper quality.

Methods

To analyze the environmental impacts in the scenarios, life cycle assessment methodology was considered. Potential environmental impacts were assessed by using the CML 2009, Dec.07 method developed by the Centre for Environmental Science from the University of Leiden.

Results and discussion

In this study, acidification potential, abiotic resources depletion potential, eutrophication potential, global warming potential, photochemical ozone creation potential, and human toxicity potential were the impact categories analyzed. Considering that the system boundaries refer only to the paper mill that was obtained, all unitary processes involved in the manufacturing of product system influence in varying proportions the impact categories chosen for evaluation. A higher concentration of contaminants leads to a higher amount of energy and water used, and thus, a significant amount of waste and emissions generated. Simulations performed have highlighted the importance of sorting technology that influences the quality of raw material that will be used.

Conclusions

Utilization of recovered paper batches with a low quality contributes to an increased environmental impact associated with the testliner paper manufacturing stage. A low quality of recovered paper will influence energy consumption in different modules of the system (recycled fiber pulp preparation, paper machine, and wastewater treatment), the volume of waste generated, and consequently the emissions released both in air and water.     

Environmental impact assessment of centralized municipal wastewater management in Thailand

Purpose

Urbanization and industrial development intensify water utilization and wastewater generation. The efficiency of wastewater treatment systems varies and depends on system design and wastewater condition. The research aims to examine seven existing centralized municipal wastewater treatment plants (WWTPs) in Bangkok to discover which system configuration yields the best environmental and economic performance. The degree of environmental impact and operational costs from different system designs were investigated to help select future wastewater treatment systems.

Methods

Life cycle assessment (LCA) has been conducted to evaluate environmental impacts from centralized municipal wastewater treatment systems. Life cycle impact assessment method based on endpoint modeling (LIME) was applied, with three major potential environmental impact categories including eutrophication, global warming, and acidification. All seven centralized municipal WWTPs in Bangkok were investigated as case studies. The system configurations are classified into five types of activated sludge (AS) systems. The contribution of impacts from individual processes in each type of AS system was analyzed. The methodology covered major on-site and off-site operational processes excluding construction and maintenance phases. Average annual data were calculated to develop an inventory dataset. JEMAI-Pro software was utilized in this study to analyze the life cycle impact of the systems.

Results and discussion

The level of environmental impact from a WWTP depends on the configuration of the AS system. The highest potential environmental impact from a municipal WWTP is eutrophication, which is obviously affected by ammonium and phosphorous discharges into water bodies. The vertical loop reactor activated sludge (VLRAS) system yielded the best treatment performance among the five AS sub-systems. The consumption of electricity used to operate the system contributed significantly to global warming potential and correlated considerably with operating costs. Comparing among three system sizes, the large-scale WWTP revealed inefficient electricity consumption, whereas the medium plant provided better performance in chemical use and operating costs.

Conclusions

Centralized municipal WWTPs with capacities ranging from 10 to 350?×?10³ m³/day were evaluated with respect to environmental performance and costs during the operating phase. Among all case studies, a medium-scale WWTP with a VLRAS system offered the best operating performance in terms of low environmental impact, resource consumption, and cost. To enhance WWTP management, it is vital to improve the efficiency of electricity consumption in primary and secondary treatment processes and increase wastewater collection efficiency to maximize the plant operating capacity and minimize overall environmental impacts.

     

Life cycle energy consumption and CO2 emission of an office building in China

Purpose  

Building is one of the main factors of energy use and greenhouse gas emissions. Reducing energy consumption and carbon dioxide (CO₂) emission from building is urgent for environmental protection and sustainable development. The objective of this study is to develop a life cycle assessment (LCA) model for an office building in China to assess its energy consumption and CO₂ emission, determine the whole life cycle phases, and the significant environmental aspects that contribute most to the impact.     

Reducing the impact of irrigated crops on freshwater availability: the case of Brazilian yellow melons

Purpose

This study quantifies freshwater consumption throughout the life cycle of Brazilian exported yellow melons and assesses the resulting impact on freshwater availability. Results are used to identify improvement options. Moreover, the study explores the further impact of variations in irrigation volume, yield, and production location.

Methods

The product system boundary encompasses production of seeds, seedlings, and melon plants; melon packing; disposal of solid farm waste; and farm input and melon transportation to European ports. The primary data in the study were collected from farmers in order to quantify freshwater consumption related to packing and to production of seeds, seedlings, and melons. Open-field melon irrigation was also estimated, considering the region's climate and soil characteristics. Estimated and current water consumptions were compared in order to identify impact reduction opportunities. Sensitivity analysis was used to evaluate variations in the impact because of changes in melon field irrigation, yield, and farm location.

Results and discussion

This study shows that the average impact on freshwater availability of 1 kg of exported Brazilian yellow melons is 135 l H₂O-e, with a range from 17 to 224 l H₂O-e depending on the growing season's production period. Irrigation during plant production accounts for 98 % of this impact. Current melon field water consumption in the Low Jaguaribe and Açu region is at least 39 % higher than necessary, which affects the quality of fruits and yield. The impact of melon production in other world regions on freshwater availability may range from 0.3 l H₂O-e/kg in Costa Rica to 466 l H₂O-e/kg in the USA.

Conclusions

The impact of temporary crops, such as melons, on water availability should be presented in ranges, instead of as an average, since regional consumptive water and water stress variations occur in different growing season periods. Current and estimated water consumption for irrigation may also be compared in order to identify opportunities to achieve optimization and reduce water availability impact.     

A conceptual framework for impact assessment within SLCA

Purpose  

This paper aims at spelling out the area of protection (AoP), namely the general concept of human well-being and the impact categories in social life cycle assessment (SLCA). The applicability of the so-called capabilities approach—a concept frequently used for evaluating human lives—is explored. It is shown how the principles of the capabilities approach can be transferred to the impact assessment within SLCA.     

Categorizing water for LCA inventory

Purpose  

As impact assessment methods for water use in LCA evolve, so must inventory methods. Water categories that consider water quality must be defined within life cycle inventory. The method presented here aims to establish water categories by source, quality parameter and user.     

Classification of chemicals into emission-based impact categories: a first approach for equiprobable and site-specific conceptual frames

Purpose  

The classification step is systematically neglected in the calculation of life cycle impact assessment indicators: for several direct contribution of one pollutant to several impact categories, the distribution between these impact categories is not accounted. The proposed approaches of non-redundant classification are based on the probability that an emitted substance and its chemically degraded forms are involved into several environmental impacts.     

Assessing potential desertification environmental impact in life cycle assessment

Background, aim and scope  

Life cycle assessment (LCA) enables the objective assessment of global environmental burdens associated with the life cycle of a product or a production system. One of the main weaknesses of LCA is that, as yet, there is no scientific agreement on the assessment methods for land-use related impacts, which results in either the exclusion or the lack of assessment of local environmental impacts related to land use. The inclusion of the desertification impact in LCA studies of any human activity can be important in high-desertification risk regions.     

Water supply and sustainability: life cycle assessment of water collection, treatment and distribution service

Purpose

The aim of the present paper is to describe the development of a life cycle assessment study of the service of potable water supply in Sicily, Italy. The analysis considers the stages of collection, treatment and distribution of potable water through the regional network, whilst the use stage of water is not included.

Methods

The selection of a methodological pattern coherently with the requirements of an environmental label, such as the EPDs, aims at allowing comparability among different studies.

Results and discussion

The analysis shows the shares of impacts along the life cycle chain, i.e. outputs by well fields and spring groups, purification and desalination plants, water losses in the waterworks, electrical consumption of waterworks systems and impacts of network maintenance. With regard to global warming potential (GWP), the impact of purification plants represents a 6–7 % share of the total, whilst desalination is at 74 %. Water losses in the waterworks show an impact of 15–17 %; the contribution owing to electrical consumption of waterworks systems and network maintenance results to be 3 %. Desalination plants represent the major contribution to all impact categories considered.

Conclusions

In respect to management issues, the most relevant impact categories resulted to be GWP, non-renewable energy resources and water consumption. Since the results for non-renewable energy resources are strictly connected to GWP emissions, carbon footprint and water footprint can be profitably used as single-issue indicators without the risk of burden shifting in studies aiming to evaluate the impact of potable water distribution.     

ReCiPe2016: a harmonised life cycle impact assessment method at midpoint and endpoint level

Purpose

Life cycle impact assessment (LCIA) translates emissions and resource extractions into a limited number of environmental impact scores by means of so-called characterisation factors. There are two mainstream ways to derive characterisation factors, i.e. at midpoint level and at endpoint level. To further progress LCIA method development, we updated the ReCiPe2008 method to its version of 2016. This paper provides an overview of the key elements of the ReCiPe2016 method.

Methods

We implemented human health, ecosystem quality and resource scarcity as three areas of protection. Endpoint characterisation factors, directly related to the areas of protection, were derived from midpoint characterisation factors with a constant mid-to-endpoint factor per impact category. We included 17 midpoint impact categories.

Results and discussion

The update of ReCiPe provides characterisation factors that are representative for the global scale instead of the European scale, while maintaining the possibility for a number of impact categories to implement characterisation factors at a country and continental scale. We also expanded the number of environmental interventions and added impacts of water use on human health, impacts of water use and climate change on freshwater ecosystems and impacts of water use and tropospheric ozone formation on terrestrial ecosystems as novel damage pathways. Although significant effort has been put into the update of ReCiPe, there is still major improvement potential in the way impact pathways are modelled. Further improvements relate to a regionalisation of more impact categories, moving from local to global species extinction and adding more impact pathways.

Conclusions

Life cycle impact assessment is a fast evolving field of research. ReCiPe2016 provides a state-of-the-art method to convert life cycle inventories to a limited number of life cycle impact scores on midpoint and endpoint level.

     

Water demand and stress from oil palm-based biodiesel production in Thailand

Purpose

The use and production of biofuels have been strongly promoted in Thailand. In order to achieve a 25 % renewable energy target in 2021, feedstock expansion is needed to satisfy the increased demand for biofuel production putting more pressure on freshwater resources. This is an important implication of biofuel production which has not yet been taken into consideration. Thus, this study intends to address the impact from freshwater use due to the biodiesel target based on life cycle assessment approach as well as to evaluate suitable areas for expansion of oil palm.

Methods

The amount of water for growing oil palm throughout its lifespan is estimated based on theoretical crop water requirement, while water demand for producing biodiesel is referred to from literature. Then, the potential impact on freshwater resources is assessed in terms of water deprivation using the water stress index of Thailand. The Alternative Energy Development Plan for 2012–2021 and areas recommended by the Ministry of Agriculture and Cooperatives are referred in this study. Additionally, two scenarios for increasing new plantation in suitable areas are proposed as expansion in a single region or spread over the three regions.

Results and discussion

The highest water requirement for oil palm-based biodiesel production is found in the central region followed by the eastern and southern (4–9, 5–16, and 4–19 m³ L^?1 biodiesel, respectively). This is because oil palm plantations in the central region are not yet fully mature. As a result, the ratio of crop water requirement associated to crop productivity will be reduced while the water productivity will be increased yearly in yield. Also, more than 99 % of the total water is required during the cultivation period. To achieve the 2021 biodiesel target with a concern towards the impact from freshwater use by means of low water deprivation, cultivating oil palm is recommended entirely in the eastern and the southern parts without expansion to the central region.

Conclusions

The impact on freshwater resources is an important implication of biofuel production as most of the water requirement of palm oil biodiesel was for oil palm cultivation. Accounting the water deprivation as one of the criteria on impact from freshwater use will provide useful support for selecting areas having less potential for inducing water stress in a watershed leads to people in these areas being less vulnerable to water stress.

     

Cradle to gate environmental impact assessment of acrylic fiber manufacturing

Purpose

The aim of the current study was to analyze the impacts of acrylic fiber manufacturing on the environment and to obtain information for assisting decision makers in improving relevant environmental protection measures for green field investments in developing countries especially in Africa and Middle East and North Africa (MENA) regions. The key research questions were as follows: what are the different impacts of acrylic fiber manufacturing on the environment and which base material has the highest impact?

Methods

The life cycle assessment (LCA) started from obtaining the raw material until the end of the production process (cradle to gate analysis). Focus was given on water consumption, energy utilization in acrylic fiber production, and generated waste from the industry. The input and output data for life cycle inventory was collected from an acrylic fiber manufacturing plant in Egypt. SimaPro software was used to calculate the inventory of twelve impact categories that were taken into consideration, including global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), carcinogen potential (CP), ecotoxicity potential (ETP), respiratory inorganic formation potential (RIFP), respiratory organic formation potential (ROFP), radiation potential (RP), ozone layer depletion (OLD), mineral depletion (MD), land use (LU), and fossil fuel depletion (FFD).

Results and discussion

LCA results of acrylic fiber manufacturing on the environment show that 82.0 % of the impact is on fossil fuel depletion due to the high-energy requirement for acrylonitrile production, 15.9 % of the impact is on human health, and 2.1 % on ecosystem quality. No impacts were detected on radiation potential, ozone layer depletion, land use, mineral depletion, or human respiratory system due to organic substances.

Conclusions

Based on these study results, it is concluded that acrylic fiber manufacturing is a high-energy consumption industry with the highest impact to be found on fossil fuel depletion and human health. This study is based on modeling the environmental effects of the production of 1-kg acrylic fiber and can serve to estimate impacts of similar manufacturing facilities and accordingly use these results as an indicator for better decision-making.

     

Water footprint of livestock: comparison of six geographically defined beef production systems

Purpose  

Water use in the livestock sector has featured in the debate about sustainable food systems. Most evidence has come from virtual water calculations which lack impact assessment and adequate consideration of the heterogeneity in livestock production. This study sought new evidence, using a recently developed life cycle impact assessment method for water use to assess six geographically defined beef cattle production systems in New South Wales, Australia, a major production region.     

Ecodesign requirements for televisions—is energy consumption in the use phase the only relevant requirement?

Purpose

This paper concerns the Ecodesign Directive (2009/125/EC) and the implementing measures (IM) in which ecodesign requirements are set up for energy-using and energy-related products. Previous studies have found that the requirements have a unilateral focus on energy consumption and the use phase. This is not in line with the scientific understanding of ecodesign, where attention should be put on all life cycle phases and all relevant environmental impact categories. This study focuses on the requirements for televisions (TV). A life cycle assessment (LCA) is carried out on two TVs to analyse if other environmental hotspots and life cycle phases should be included in the requirements in the IM of the Ecodesign Directive besides energy consumption in the use phase analysis.

Methods

The consequential approach is used. The data for the LCA have been gathered from two manufacturers of TVs. In one case, the data were delivered in Excel spreadsheets; in the other case, the authors of this paper together with the manufacturer disassembled a TV and collected the data manually.

Results and discussion

When applying the consequential approach, the production phase has the highest environmental impact, which is in contradiction with the focus area of the IM. The result of the sensitivity analysis is that the source of electricity is a potentially significant contributor of uncertainty. However, even in a coal-based scenario, the contribution from the production phase is approximately 30 %.

Conclusions

Based on these results, it is concluded that for future requirement setting in IM, it is necessary to set up requirements that cover more life cycle phases of the product in order to address the most important impacts.     

Climatic impact of land use in LCA—carbon transfers between vegetation/soil and air

Background, aim, and scope  

Human use of land areas leads to impacts on nature in several ways. Within the framework of the UNEP/SETAC Life Cycle Initiative, it was stated that life cycle assessment (LCA) of land use should assess at least the impact on biodiversity, the impact on biotic production, and the impact on the regulating functions of the natural environment. This study focuses on the climatic impact of land use as determined by the CO₂ transfers between vegetation/soil and the atmosphere in the course of terrestrial release and re-storage of carbon.