Practical life cycle assessment through streamlining

Life cycle assessment (LCA) provides a concept, framework, and method to identify and evaluate the environmental burdens of products and processes. An ongoing concern of companies trying to implement LCA is the value of LCA in supporting actual decisions versus the resources and time needed to conduct a “full” LCA. In response to these concerns, there has been a lot of activity surrounding the “streamlining” of LCA to keep it more manageable yet provide useful and acceptably accurate results. This article explores the concept of streamlining, discusses where and how streamlining decisions can be made in an LCA, and presents issues related to conducting more streamlined LCAs. Due to the wide variety of purposes and scenarios in which LCAs are conducted, it is difficult to devise a one-size-fits-all method for streamlining. Instead, we have focused on presenting the streamlining options in the context of major decision points that are common to most LCAs.     

Value chain for next-generation biofuels: resilience and sustainability of the product life cycle

Multiple factors including climate change, price uncertainties, and geopolitical instability have prompted many industries to investigate the feasibility of replacing traditional petroleum-based fuels with biofuel alternatives. However, to make this transition successful, these new biofuels must be environmentally sustainable and the necessary support infrastructure must be in place to make the production, distribution, and storage of these biofuels technologically feasible and cost effective. Developing a value chain, spanning from feedstock production to distribution to end users, requires garnering buy-in from multiple stakeholders by demonstrating environmental, economic, and social benefits and incentives. Two critical factors are the environmental benefits achieved from the use of the biofuel technology and the degree of resilience of the value chain to emergent conditions to ensure steady supply to consumers. Moreover, different biofuel pathways have different costs, benefits, and risks which must be compared. In this paper, we describe how environmental sustainability can be modeled using life cycle assessment (LCA) and how the resilience of value chain initiatives can be modeled using a scenario-based decision model. We then describe how sustainability and resilience assessments can be integrated in an iterative, anticipatory LCA framework. These assessments can be used as the basis for a business case for various investments, as well as a means for promoting responsible innovations, with the aviation industry used as a case study.     

AHP based life cycle sustainability assessment (LCSA) framework: a case study of six storey wood frame and concrete frame buildings in Vancouver

Construction and building industry is in dire need for developing sustainability assessment frameworks that can evaluate and integrate related environmental and socioeconomic impacts. This paper discusses an analytic hierarchy process (AHP) based sustainability evaluation framework for mid-rise residential buildings based on a broad range of environmental and socioeconomic criteria. A cradle to grave life cycle assessment technique was applied to identify, classify, and assess triple bottom line (TBL) sustainability performance indicators of buildings. Then, the AHP was applied to aggregate the impacts into a unified sustainability index. The framework is demonstrated through a case study to investigate two six storey structural systems (i.e. concrete and wood) in Vancouver, Canada. The results of this paper show that the environmental performance of a building in Canada, even in regions with milder weather such as Vancouver, is highly dependent on service life energy, rather than structural materials.     

Greenhouse gas emissions from forestry operations: a life cycle assessment

Most forest carbon assessments focus only on biomass carbon and assume that greenhouse gas (GHG) emissions from forestry activities are minimal. This study took an in-depth look at the direct and indirect emissions from Pacific Northwest (PNW) Douglas-fir [Pseudotsuga menziesii (Mirbel) Franco] forestry activities to support or deny this claim. Greenhouse gas budgets for 408 "management regimes" were calculated using Life Cycle Assessment (LCA) methodology. These management regimes were comprised of different combinations of three types of seedlings (P + 1, 1 + 1, and large plug), two types of site preparation (pile and burn, and chemical), 17 combinations of management intensity including fertilization, herbicide treatment, pre-commercial thinning (PCT), commercial thinning (CT), and nothing, and four different rotation ages (30, 40, 50, and 60 yr). Normalized to 50 yr, average direct GHG emissions were 8.6 megagrams (Mg) carbon dioxide equivalents (CO2e) ha(-1), which accounted for 84% of total GHG emissions from the average of 408 management regimes. Harvesting (PCT, CT, and clear cutting) contributed the most to total GHG emissions (5.9 Mg CO2e per 700 m3 harvested timber), followed by pile and burn site preparation (4.0 Mg CO2e ha(-1) or 32% of total GHG emissions) and then fertilization (1.9 Mg CO2e ha(-1) or 15% of total GHG emissions). Seedling production, seedling transportation, chemical site preparation, and herbicide treatment each contributed less than 1% of total GHG emissions when assessed per hectare of planted timberland. Total emissions per 100 m3 averaged 1.6 Mg CO2e ha(-1) over all 408 management regimes. An uncertainty analysis using Monte Carlo simulations revealed that there are significant differences between most alternative management regimes.     

Hybrid life cycle assessment for asphalt mixtures with high RAP content

With the pavement industry adopting sustainable practices to align itself with the global notion of habitable environments, there has been growing use of life-cycle assessment (LCA). A hybrid LCA was used to analyze the environmental footprint of using a reclaimed asphalt pavement (RAP) content in asphalt binder mixtures. The analysis took into consideration the material, construction, and maintenance and rehabilitation phases of the pavement life cycle. The results showed significant reductions in energy consumption and greenhouse gas (GHG) emissions with an increase in RAP content. The contribution of the construction phase to the GHGs and energy consumption throughout pavement life cycle is minimal. Feedstock energy, though not consequential when comparing asphalt mixtures only, has a significant impact on total energy. Based on LCA analysis performed for various performance scenarios, breakeven performance levels were identified for mixtures with RAP. The study highlighted the importance of achieving equivalent field performance for mixtures with RAP and virgin mixtures.     

Outsourcing sustainability: a game-theoretic modeling approach

As a response to stakeholders’ interest in sustainable products and services, an organization may change its approach to sustainability issues, from isolated social and environmental projects to corporate sustainability strategies and practices that are part of their core business. However, many of the efforts associated with these sustainability strategies cannot be directly exerted by focal organizations. We consider the situation in which a focal organization (sustainability buyer) outsources sustainability efforts to another organization (sustainability seller). While buyers cannot directly exert sustainability efforts, they can provide economic or technical support to their sellers in order to incentivize these efforts. We investigate how the effort and support decisions change according to characteristics of stakeholders, buyers, and sellers. Additionally, the presence of sustainability-minded stakeholders may lead to buyers’ competition on the sustainability effort exerted by their sellers. Therefore, we extend our analysis of sustainability efforts and incentives to the case of two competing buyers, and we determine conditions under which sharing a seller is preferred by the buyers to having a separate seller for each buyer.     

On the usefulness of life cycle assessment of packaging

In reaction to a paper inEnvironmental Management in which the sense and sensibility of environmental assessments of packaging were questioned, it is argued that these types of assessments may be very useful, provided the relevant types of questions are posed. These boundary conditions are discussed, along with an overview of more recent methodological developments with respect to environmental assessment of products.     

Linking carbon sequestration science with local sustainability: an integrated assessment approach

This paper introduces an integrated assessment (IA) approach for a Canada-China joint research project that linked forest carbon sequestration, forest resource management, and local sustainability enhancement. The purpose of the IA was to improve the measurement of carbon in different land uses and vegetation covers, as well as to direct decision makers to those land uses or options as an CO₂ emission reduction strategy while supporting rural sustainable development. In this connection, three questions are addressed in this paper:

1)

How will forestry carbon sequestration land use policies affect regional sustainability prospects in rural China?     

Environmental indicators for communication of life cycle impact assessment results and their applications

Life cycle impact assessment (LCIA) is performed to quantitatively evaluate all environmental impacts from products, systems, processes and services. However, LCIA does not always provide valuable information for choosing among alternatives with different specifications, functionalities and lifetimes. The objectives of this study are (1) to propose environmental indicators to evaluate environmental efficiency and value qualitatively and quantitatively on the basis of analogies to financial and economic indicators, and (2) to present the application of the indicators. Incremental evaluation using a reference is employed to obtain the environmental indicators. The environmental efficiency indicators are conceptually based on the ratios of reduced environmental burdens returned to environmental burdens required: environmental return on investment, environmental payback period and environmental internal rate of return. The environmental value indicator is the sum of all reduced and required environmental burdens: i.e., environmental net present value. All the environmental indicators can be used to compare and rank the environmental efficiencies or values of alternatives. The environmental efficiency indicators can be applied to a new environmental labeling. The concept of eco-efficiency labeling is developed by combining the environmental efficiency indicators with financial indicators. A case study is performed to illustrate the necessity and importance of the environmental indicators. These environmental indicators can help easily communicate LCIA results in the field of environmental management.     

Rapid assessment of sustainability in Mainland China

This paper presents an approach for rapid assessment of sustainability for Mainland China based on a multilayer index system. Efficient assessment is conducted with the basic mapping units at county and city levels. After evaluating a comprehensive sustainable development index, SDI, for each unit, five rankings of sustainability are determined, and a zonation map produced. Regional characteristics and differences are interpreted through macro-analysis of the spatial variation in SDI. A sensitivity analysis is performed by which the weights of the sub-indices are altered by ±20%, and SDI re-evaluated; the resulting grades remain the same, thus confirming the robustness of the technique. Moreover, the accuracy of the proposed approach is indirectly validated by comparison with assessment results from an alternative systems analysis method. It is found that major conurbations such as Beijing have relatively high levels of sustainability, whereas provinces in central and western China require investment to improve their sustainability.     

Energy and entropy: a thermodynamic approach to sustainability

Thermodynamics is a basic science that formulates the rules for the conversion of energy and matter from one form into another. It sets the physical limits for the evolution of and the developments in the world around us. In contradiction to the mechanical approach, thermodynamics indicates that economic growth leads to increasing disorder. More specifically, increasing the flows of energy and matter through society, as happens in the process of ongoing industrialization, leads to progressive depletion of available energy and matter or, otherwise stated, to increased entropy. Excessive entropy production is reflected in natural disorders such as the greenhouse effect, ozone holes, environmental pollution, etc. Sustainable development can only be approached by imposing a close to steady-state lifestyle on mankind.     

Criteria and indicators of forest sustainability assessment for Cameroon

Against a backdrop of continuous deforestation and the degradation of forest resources, this paper is an attempt to develop auspicious criteria and indicators of forest sustainability for Cameroon, drawing from the strength and weaknesses of those currently applicable. Using data emanating from both secondary and primary sources, this paper concludes that while the adoption and implementation of the criteria for forest sustainability should normally lead to sustainability, it should not be taken for granted because sustainability is not an abstract concept, but measurable. Thus, whether or not forest in Cameroon is sustainable can only be ascertained through the effective application of the criteria and indicators delineated in this paper.     

Infrastructure development through PPPs in India: criteria for sustainability assessment

Public private partnerships (PPPs) allow the Indian Government to leverage private capital for meeting the widening demand-supply gap in the provision of infrastructure services. The private sector, however, prefers to limit the participation to financially attractive projects only, thereby resulting in patterns of infrastructure creation impeding the progress towards sustainable development. In order to promote sustainable development, the PPP procurement process should focus on incentivising the private sector for sustainable infrastructure development rather than concentrating on ensuring financial sustainability only. This paper discusses the principles-based PPP-specific framework that has been developed to facilitate assessment of PPP projects' progress towards sustainable development. The framework development was based on a holistic approach to sustainability assessment and subsequently validated through questionnaire survey with key stakeholders in the Indian PPP programme. This framework will provide the decision makers with appropriate decision aid for integration of sustainable development principles in the PPP procurement process.     

Methodological aspects of life cycle assessment of integrated solid waste management systems

Environmental life cycle assessment (LCA) developed rapidly during the 1990s and has reached a certain level of harmonisation and standardisation. LCA has mainly been developed for analysing material products, but can also be applied to services, e.g. treatment of a particular amount of solid waste. This paper discusses some methodological issues which come into focus when LCAs are applied to solid waste management systems. The following five issues are discussed. (1) Upstream and downstream system boundaries: where is the ‘cradle’ and where is the ‘grave’ in the analysed system? (2) Open-loop recycling allocation: besides taking care of a certain amount of solid waste, many treatment processes also provide additional functions, e.g. energy or materials which are recycled into other products. Two important questions which arise are if an allocation between the different functions should be made (and if so how), or if system boundaries should be expanded to include several functions. (3) Multi-input allocation: in waste treatment processes, different materials and products are usually mixed. In many applications there is a need to allocate environmental interventions from the treatment processes to the different input materials. The question is how this should be done. (4) Time: emissions from landfills will continue for a long time. An important issue to resolve is the length of time emissions from the landfill should be considered. (5) Life cycle impact assessment: are there any aspects of solid waste systems (e.g. the time horizon) that may require specific attention for the impact assessment element of an LCA? Although the discussion centres around LCA it is expected that many of these issues are also relevant for other types of systems analyses.     

Integrating industrial ecology principles into a set of environmental sustainability indicators for technology assessment

This paper focuses on the environmental component of sustainability of technology, taking into account the role of industrial ecology. Assessment of environmental sustainability of technology traditionally focuses on immediate impact of technology on the environment through quantifying resource extraction and generated emissions. However, technology does not only exchange materials with the environment but also with the industrial society as a whole, the so-called industrial metabolism. A higher compatibility of a specific technology with the industrial system, as studied in industrial ecology, can result in lower resource extraction and reduced waste emission, indirectly contributing to a better environmental sustainability.Starting from the considerations above and based on the second law of thermodynamics, the paper presents a set of five environmental sustainability indicators for the assessment of products and production pathways, integrating industrial ecology principles. The indicators, all scaled between 0 and 1, take into account: (1) renewability of resources; (2) toxicity of emissions; (3) input of used materials; (4) recoverability of products at the end of their use; (5) process efficiency.The applicability of the elaborated set of indicators is illustrated for different production pathways of alcohols (petrochemical and oleochemical based), polyethylene end-of-life options and electricity production from non-renewable (natural gas and fossil oil) and renewable resources (hydropower, photovoltaic conversion of solar irradiation).     

Environmental sustainability in an agricultural development project: a system dynamics approach

Regional agricultural projects based on water resource development have many potential impacts on social and natural environments. In this research, potential long-term environmental problems of the Southeastern Anatolian Project (GAP) related to water resources, land use, land degradation, agricultural pollution and demography are analysed from a systems perspective. The analysis focuses on the totality of environmental, social and economic issues. For this purpose, a system dynamics simulation model (GAPSIM) has been developed as an experimental platform for policy analysis. GAPSIM was validated, first 'structurally', using the tests suggested by the literature and then the model 'behaviour' was tested and calibrated with respect to available data. The reference behaviour of GAPSIM reveals that, as the irrigated lands are developed, GAP faces significant water scarcity because of the increased intensity of cotton, the crop with the highest demands for water. Simulation results also indicate that two key environmental factors, pesticide and fertilizer consumption may reach undesirable levels. Alternative irrigation water release strategies, development rates of irrigated fields and farm rotation practices appear as important policy tools in achieving long-term environmental sustainability. GAPSIM promises to be not only a useful laboratory for policy makers of GAP, but also a useful generic structure applicable to other similar regional development projects.     

基于生命周期分新的电解铝清洁生产评价指标研究

本文利用生命周期评价对电解铝生产过程进行了全面分析，结合清洁生产的内涵和电解铝生产工艺的系统边界图，从炭素阳极、电解制铝、铝加工和烟气净化等四个子模块出发，把电解铝清洁生产评价指标体系分为五项一级指标，即管理与工艺设备指标、资源消耗指标、产品指标、环境指标、废物回收利用指标，一级指标又分解为13项二级指标和28项三级指标。     

基于生命周期分析的电解铝清洁生产评价指标研究

本文利用生命周期评价对电解铝生产过程进行了全面分析,结合清洁生产的内涵和电解铝生产工艺的系统边界图,从炭素阳极、电解制铝、铝加工和烟气净化等四个子模块出发,把电解铝清洁生产评价指标体系分为五项一级指标,即管理与工艺设备指标、资源消耗指标、产品指标、环境指标、废物回收利用指标,一级指标又分解为13项二级指标和 28项三级指标。