Lifting the fog on characteristics and limitations of hybrid LCA—a reply to “Does hybrid LCA with a complete system boundary yield adequate results for product promotion?” by Yi Yang (Int J Life Cycle Assess 22(3):456–406, doi:10.1007/s11367-016-1256-9

2017 ◽  
Vol 22 (6) ◽  
pp. 1005-1008 ◽  
Author(s):  
Thomas Gibon ◽  
Thomas Schaubroeck
Keyword(s):  
Life Cycle ◽  
Complete System ◽  
Life Cycle Assess ◽  
System Boundary ◽  
Hybrid Lca ◽  
Product Promotion

scholarly journals A Comprehensive Framework for Standardising System Boundary Definition in Life Cycle Energy Assessments

Buildings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 230
Author(s):  
Hossein Omrany ◽  
Veronica Soebarto ◽  
Jian Zuo ◽  
Ruidong Chang
Keyword(s):  
Life Cycle ◽  
Energy Use ◽  
Embodied Energy ◽  
Building Energy Efficiency ◽  
System Boundary ◽  
Policy Makers ◽  
Energy Assessment ◽  
Boundary Definition ◽  
Comprehensive Framework

This paper aims to propose a comprehensive framework for a clear description of system boundary conditions in life cycle energy assessment (LCEA) analysis in order to promote the incorporation of embodied energy impacts into building energy-efficiency regulations (BEERs). The proposed framework was developed based on an extensive review of 66 studies representing 243 case studies in over 15 countries. The framework consists of six distinctive dimensions, i.e., temporal, physical, methodological, hypothetical, spatial, and functional. These dimensions encapsulate 15 components collectively. The proposed framework possesses two key characteristics; first, its application facilitates defining the conditions of a system boundary within a transparent context. This consequently leads to increasing reliability of obtained LCEA results for decision-making purposes since any particular conditions (e.g., truncation or assumption) considered in establishing the boundaries of a system under study can be revealed. Second, the use of a framework can also provide a meaningful basis for cross comparing cases within a global context. This characteristic can further result in identifying best practices for the design of buildings with low life cycle energy use performance. Furthermore, this paper applies the proposed framework to analyse the LCEA performance of a case study in Adelaide, Australia. Thereafter, the framework is utilised to cross compare the achieved LCEA results with a case study retrieved from literature in order to demonstrate the framework’s capacity for cross comparison. The results indicate the capability of the framework for maintaining transparency in establishing a system boundary in an LCEA analysis, as well as a standardised basis for cross comparing cases. This study also offers recommendations for policy makers in the building sector to incorporate embodied energy into BEERs.

A systematic review of life cycle assessment of hydrogen for road transport use

2021 ◽  
Author(s):  
Dyah Ika Rinawati ◽  
Alexander Ryota Keeley ◽  
Shutaro Takeda ◽  
Shunsuke Managi
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Hydrogen Production ◽  
Case Studies ◽  
Large Scale ◽  
Road Transport ◽  
Fuel Cell Vehicle ◽  
Intergovernmental Panel ◽  
Hybrid Lca ◽  
Complete Life Cycle

Abstract This study conducted a systematic literature review of the technical aspects and methodological choices in life cycle assessment (LCA) studies of using hydrogen for road transport. More than 70 scientific papers published during 2000–2021 were reviewed, in which more than 350 case studies of use of hydrogen in the automotive sector were found. Only some studies used hybrid LCA and energetic input-output LCA, whereas most studies addressed attributional process-based LCA. A categorization based on the life cycle scope distinguished case studies that addressed the well-to-tank (WTT), well-to-wheel (WTW), and complete life cycle approaches. Furthermore, based on the hydrogen production process, these case studies were classified into four categories: thermochemical, electrochemical, thermal-electrochemical, and biochemical. Moreover, based on the hydrogen production site, the case studies were classified as centralized, on-site, and on-board. The fuel cell vehicle passenger car was the most commonly used vehicle. The functional unit for the WTT studies was mostly mass or energy, and vehicle distance for the WTW and complete life cycle studies. Global warming potential (GWP) and energy consumption were the most influential categories. Apart from the GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model and the Intergovernmental Panel on Climate Change for assessing the GWP, the Centrum voor Milieukunde Leiden method was most widely used in other impact categories. Most of the articles under review were comparative LCA studies on different hydrogen pathways and powertrains. The findings provide baseline data not only for large-scale applications, but also for improving the efficiency of hydrogen use in road transport.

scholarly journals The assessment of positive impacts in LCA of products

2020 ◽  
Author(s):  
Pim R. Croes ◽  
Walter J.V. Vermeulen
Keyword(s):  
Life Cycle ◽  
Positive Impact ◽  
Current Status ◽  
Life Cycle Assess ◽  
Great Caution ◽  
Rebound Effects ◽  
Stakeholder Groups ◽  
Negative Impacts ◽  
Definition Of ◽  
Positive Impacts

Abstract Purpose The objective of this paper is to open a discussion on the implications and challenges of including positive impacts in LCAs of products and to propose a set of criteria for their inclusion in LCA in general and in the Oiconomy system in particular. Methods Using the existing literature, guided by the recent reviews by Di Cesare et al. (2018), Petti et al. (2016), and Ekener-Petersen et al. (Int J Life Cycle Assess 23(3):1–13, 2016) and our own experience and logic, we assess ethical and practical issues, shortcomings, potential inconsistencies, and problems of inclusion of positive impacts and propose criteria for inclusion of positive impacts in LCA. Results Discussed in relation to the inclusion of positive impacts in LCA are the conflicting descriptive and prescriptive character of LCA, the inclusion of internalities, considering “absence of negative impacts” as positive, measuring by status or by change and the therewith involved temporal scope, moral consequences of comparing positive and negative impacts to different stakeholder groups, the requirement of a capacity-raising character and maintenance of a positive impact, rebound effects, R&D, background and foreground data on positive impacts, and the inclusion of employment and product utilities as positive impacts. Based on this assessment, we propose a set of criteria for the assessment of positive impacts in life cycle assessment in general and especially of positive contributions in the “Oiconomy system”. Conclusions This study demonstrates several serious ethical and practical issues and challenges related to inclusion of positive impacts in LCA. An especially difficult question is how to interpret the economic concepts of “externalities” and “internalities” in relation to LCA. A special definition of in- and externalities for LCA purposes is proposed. The importance of a “capacity-raising” character of a positive impact is demonstrated, but also some of the difficulties of distinguishing capacity raising from maintaining the current status. Important outcomes are that for a consistent LCA, inclusion of most internalities and absence of negative impacts must be dissuaded, which also applies to employment and wages unless without a range of additional criteria. Great caution must be taken with inclusion of product utilities, comparing the positives for one stakeholder group with the negatives for another and mixing measurement by status with measurement by change.

scholarly journals Application of Life Cycle Energy Assessment in Residential Buildings: A Critical Review of Recent Trends

2020 ◽  
Vol 12 (1) ◽  
pp. 351 ◽  
Author(s):  
Hossein Omrany ◽  
Veronica Soebarto ◽  
Ehsan Sharifi ◽  
Ali Soltani
Keyword(s):  
Life Cycle ◽  
Energy Consumption ◽  
Energy Use ◽  
Residential Buildings ◽  
Current Trend ◽  
Energy Performance ◽  
Embodied Energy ◽  
System Boundary ◽  
Energy Assessment ◽  
Boundary Definition

Residential buildings are responsible for a considerable portion of energy consumption and greenhouse gas emissions worldwide. Correspondingly, many attempts have been made across the world to minimize energy consumption in this sector via regulations and building codes. The focus of these regulations has mainly been on reducing operational energy use, whereas the impacts of buildings’ embodied energy are frequently excluded. In recent years, there has been a growing interest in analyzing the energy performance of buildings via a life cycle energy assessment (LCEA) approach. The increasing amount of research has however caused the issue of a variation in results presented by LCEA studies, in which apparently similar case studies exhibited different results. This paper aims to identify the main sources of variation in LCEA studies by critically analyzing 26 studies representing 86 cases in 12 countries. The findings indicate that the current trend of LCEA application in residential buildings suffers from significant inaccuracy accruing from incomplete definitions of the system boundary, in tandem with the lack of consensus on measurements of operational and embodied energies. The findings call for a comprehensive framework through which system boundary definition for calculations of embodied and operational energies can be standardized.

System Boundary Selection in Life-Cycle Inventories Using Hybrid Approaches

2004 ◽  
Vol 38 (3) ◽  
pp. 657-664 ◽  
Author(s):  
Sangwon Suh ◽  
Manfred Lenzen ◽  
Graham J. Treloar ◽  
Hiroki Hondo ◽  
Arpad Horvath ◽  
...  
Keyword(s):  
Life Cycle ◽  
System Boundary ◽  
Life Cycle Inventories ◽  
Hybrid Approaches

An Exergy-Based Framework for Assessing Sustainability of IT Systems

2009 ◽  
Author(s):  
Amip J. Shah ◽  
Milton Meckler
Keyword(s):  
Life Cycle ◽  
Boundary Conditions ◽  
Life Cycle Analysis ◽  
Second Law ◽  
Research Needs ◽  
System Boundary ◽  
First Law Of Thermodynamics ◽  
Widespread Implementation ◽  
It Systems ◽  
Sustainability Theory

This paper proposes an exergy-based approach to evaluating the sustainability of different information technology (IT) systems. In reviewing existing standards around IT sustainability, we find that most of these metrics are based on energy efficiencies. Thermodynamically, these metrics imply sufficiency of a first-law analysis. In this paper, we show that such metrics based on the first-law of thermodynamics are necessary but not sufficient for evaluating the sustainability of IT systems. We discuss how — within the context of sustainability theory — exclusively relying on first-law metrics implicitly assumes a narrow set of system boundary conditions, and we show using an exergy-based life-cycle analysis that various classes of IT systems violate these boundary conditions. Thus, we suggest the need for metrics that include a second-law component as well as a life-cycle view of the IT system. Having identified such a metric, we demonstrate applicability of the framework for a sample IT system. We conclude by reflecting upon additional research needs and challenges associated with widespread implementation of such a framework.

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