From Life Cycle Assessment to Life Cycle Management

Life cycle assessment (LCA) is a widely accepted methodology to support decision‐making processes in which one compares alternatives, and that helps prevent shifting of environmental burdens along the value chain or among impact categories. According to regulation in the European Union (EU), the movement of waste needs to be reduced and, if unavoidable, the environmental gain from a specific waste treatment option requiring transport must be larger than the losses arising from transport. The EU explicitly recommends the use of LCA or life cycle thinking for the formulation of new waste management plans. In the last two revisions of the Industrial Waste Management Programme of Catalonia (PROGRIC), the use of a life cycle thinking approach to waste policy was mandated. In this article we explain the process developed to arrive at practical life cycle management (LCM) from what started as an LCA project. LCM principles we have labeled the “3/3” principle or the “good enough is best” principle were found to be essential to obtain simplified models that are easy to understand for legislators and industries, useful in waste management regulation, and, ultimately, feasible. In this article, we present the four models of options for the management of waste solvent to be addressed under Catalan industrial waste management regulation. All involved actors concluded that the models are sufficiently robust, are easy to apply, and accomplish the aim of limiting the transport of waste outside Catalonia, according to the principles of proximity and sufficiency.     

The Role of Washing Machines in Life Cycle Assessment Studies

A key requirement for those in industry and elsewhere who wish to reduce the environmental impact of a product is to develop priorities for action. Life cycle assessment (LCA) is increasingly used to identify such priorities but can be misleading. This article draws attention to two effects that can occur when the system boundary for a product LCA is not defined correctly. We illustrate the washing machine effect by showing that in separate life cycle studies of clothing, detergents, and washing machines, the use of energy is dominated by operation of the washing machine. All three studies prioritize the use phase for action, but in an aggregated study, double counting of the use-phase impact occurs. We demonstrate the inverse washing machine effect with an example related to energy used in transport. We show that some activities that are significant on a cumulative basis consistently fall outside the chosen system boundary for individual products. A consequence is that when LCA studies are used for prioritization, they are in danger of overemphasizing the use-phase impacts and overlooking the impacts from indirect activities. These effects, which are broadly understood by LCA developers, appear not to be understood properly by those who use LCA to direct priorities for action. Therefore, practitioners should be wary of using LCA for prioritizing action, and LCA guidance documents should reflect this caution.     

A Classroom Simulation to Teach Economic Input−Output Life Cycle Assessment

Life cycle assessment (LCA) methods and tools are increasingly being taught in university courses. Students are learning the concepts and applications of process-based LCA, input−output-based LCA, and hybrid methods. Here, we describe a classroom simulation to introduce students to an economic input−output life cycle assessment (EIO-LCA) method. The simulation uses a simplified four-industry economy with eight transactions among the industries. Production functions for the transactions and waste generation amounts are provided for each industry. Students represent an industry and receive and issue purchase orders for materials to simulate the actual purchases of materials within the economy. Students then compare the simulation to mathematical representations of the model. Finally, students view an online EIO-LCA tool ( http://www.eiolca.net ) and use the tool to compare different products. The simulation has been used successfully with a wide range of students to facilitate conceptual understanding of one EIO-LCA method.     

Applying Leontief's Price Model to Estimate Missing Elements in Hybrid Life Cycle Inventories

This article presents an approach to estimate missing elements in hybrid life cycle inventories. Its development is motivated by a desire to rationalize inventory compilation while maintaining the quality of the data. The approach builds on a hybrid framework, that is, a combination of process‐ and input–output‐based life cycle assessment (LCA) methodology. The application of Leontief's price model is central in the proposed procedure. Through the application of this approach, an inventory with no cutoff with respect to costs can be obtained. The formal framework is presented and discussed. A numerical example is provided in Supplementary Appendix S1 on the Web.     

Methodological Aspects of Applying Life Cycle Assessment to Industrial Symbioses

In view of recent studies of the historical development and current status of industrial symbiosis (IS), life cycle assessment (LCA) is proposed as a general framework for quantifying the environmental performance of by‐product exchange. Recent guidelines for LCA (International Reference Life Cycle Data System [ILCD] guidelines) are applied to answer the main research questions in the IS literature reviewed. A typology of five main research questions is proposed: (1) analysis, (2) improvement, and (3) expansion of existing systems; (4) design of new eco‐industrial parks, and (5) restructuring of circular economies. The LCA guidelines were found useful in framing the question and choosing an appropriate reference case for comparison. The selection of a correct reference case reduces the risk of overestimating the benefits of by‐product exchange. In the analysis of existing systems, environmentally extended input‐output analysis (EEIOA) can be used to streamline the analysis and provide an industry average baseline for comparison. However, when large‐scale changes are applied to the system, more sophisticated tools are necessary for assessment of the consequences, from market analysis to general equilibrium modeling and future scenario work. Such a rigorous application of systems analysis was not found in the current IS literature, but would benefit the field substantially, especially when the environmental impact of large‐scale economic changes is analyzed.     

Life Cycle Assessment of Biomass‐based Combined Heat and Power Plants

Norway, like many countries, has realized the need to extensively plan its renewable energy future sooner rather than later. Combined heat and power (CHP) through gasification of forest residues is one technology that is expected to aid Norway in achieving a desired doubling of bioenergy production by 2020. To assess the environmental impacts to determine the most suitable CHP size, we performed a unit process‐based attributional life cycle assessment (LCA), in which we compared three scales of CHP over ten environmental impact categories—micro (0.1 megawatts electricity [MWe]), small (1 MWe), and medium (50 MWe) scale. The functional units used were 1 megajoule (MJ) of electricity and 1 MJ of district heating delivered to the end user (two functional units), and therefore, the environmental impacts from distribution of electricity and hot water to the consumer were also considered. This study focuses on a regional perspective situated in middle‐Norway's Nord‐ and Sør‐Trøndelag counties. Overall, the unit‐based environmental impacts between the scales of CHP were quite mixed and within the same magnitude. The results indicated that energy distribution from CHP plant to end user creates from less than 1% to nearly 90% of the total system impacts, depending on impact category and energy product. Also, an optimal small‐scale CHP plant may be the best environmental option. The CHP systems had a global warming potential ranging from 2.4 to 2.8 grams of carbon dioxide equivalent per megajoule of thermal (g CO₂‐eq/MJ_th) district heating and from 8.8 to 10.5 grams carbon dioxide equivalent per megajoule of electricity (g CO₂‐eq/MJ_el) to the end user.     

Impact Assessment of Biodiversity and Carbon Pools from Land Use and Land Use Changes in Life Cycle Assessment,Exemplified with Forestry Operations in Norway

There is a strong need for methods within life cycle assessment (LCA) that enable the inclusion of all complex aspects related to land use and land use change (LULUC). This article presents a case study of the use of one hectare (ha) of forest managed for the production of wood for bioenergy production. Both permanent and temporary changes in above‐ground biomass are assessed together with the impact on biodiversity caused by LULUC as a result of forestry activities. The impact is measured as a product of time and area requirements, as well as by changes in carbon pools and impacts on biodiversity as a consequence of different management options. To elaborate the usefulness of the method as well as its dependency on assumptions, a range of scenarios are introduced in the study. The results show that the impact on climate change from LULUC dominates the results, compared to the impact from forestry operations. This clearly demonstrates the need to include LULUC in an LCA of forestry products. For impacts both on climate change and biodiversity, the results show large variability based on what assumptions are made; and impacts can be either positive or negative. Consequently, a mere measure of land used does not provide any meaning in LCA, as it is not possible to know whether this contributes a positive or negative impact.     

A Framework for Social Life Cycle Impact Assessment (10 pp)

Goal, Scope and Background To enhance the use of life cycle assessment (LCA) as a tool in business decision-making, a methodology for Social life cycle impact assessment (LCIA) is being developed. Social LCA aims at facilitating companies to conduct business in a socially responsible manner by providing information about the potential social impacts on people caused by the activities in the life cycle of their product. The development of the methodology has been guided by a business perspective accepting that companies, on the one hand, have responsibility for the people affected by their business activities, but, on the other hand, must also be able to compete and make profit in order to survive in the marketplace. Methods A combined, bottom-up and top-down approach has been taken in the development of the Social LCIA. Universal consensus documents regarding social issues as well as consideration for the specific business context of companies has guided the determination of damage categories, impact categories and category indicators. Results Discussion, and Conclusion. The main results are the following: (1) Impacts on people are naturally related to the conduct of the companies engaged in the life cycle rather than to the individual industrial processes, as is the case in Environmental LCA. Inventory analysis is therefore focused on the conduct of the companies engaged in the life cycle. A consequence of this view is that a key must be determined for relating the social profiles of the companies along the life cycle to the product. This need is not present in Environmental LCA, where we base the connection on the physical link which exists between process and product. (2) Boundaries of the product system are determined with respect to the influence that the product manufacturer exerts over the activities in the product chain. (3) A two-layer Social LCA method with an optional and an obligatory set of impact categories is suggested to ensure both societal and company relevance of the method. The obligatory set of impact categories encompasses the minimum expectations to a company conducting responsible business. (4) A new area of protection, Human dignity and Well-being, is defined and used to guide the modelling of impact chains. (5) The Universal Declaration of Human Rights serves as normative basis for Social LCA, together with local or country norms based on socio-economic development goals of individual countries. The International Labour Organisation's Conventions and Recommendations, and the Tripartite Declaration of Principles concerning Multinational Enterprises and Social Policy, support development of the impact pathway top-down, starting from the normative basis. (6) The obligatory part of Social LCA addresses the main stakeholder groups, employees, local community and society. Recommendations and Outlook Social LCA is still in its infancy and a number of further research tasks within this new area are identified.     

Life Cycle Assessment of Urban Wastewater Reclamation and Reuse Alternatives

Continuous population growth is causing increased water contamination. Uneven distribution of water resources and periodic droughts have forced governments to seek new water sources: reclaimed and desalinated water. Wastewater recovery is a tool for better management of the water resources that are diverted from the natural water cycle to the anthropic one. The main objective of this work is to assess the stages of operation of a Spanish Mediterranean wastewater treatment plant to identify the stages with the highest environmental impact, to establish the environmental loads associated with wastewater reuse, and to evaluate alternative final destinations for wastewater. Tertiary treatment does not represent a significant increment in the impact of the total treatment at the plant. The impact of reclaiming 1 cubic meter (m³) of wastewater represents 0.16 kilograms of carbon dioxide per cubic meter (kg CO₂/m³), compared to 0.83 kg CO₂/m³ associated with basic wastewater treatment (primary, secondary, and sludge treatment). From a comparison of the alternatives for wastewater final destination, we observe that replacing potable water means a freshwater savings of 1.1 m³, whereas replacing desalinated water means important energy savings, reflected in all of the indicators. To ensure the availability of potable water to all of the population—especially in areas where water is scarce—governments should promote reusing wastewater under safe conditions as much as possible.     

Economic Allocation in Life Cycle Assessment

This article examines methods for analyzing allocation in life cycle assessment (LCA); it focuses on comparisons of economic allocation with other feasible alternatives. The International Organization for Standardization's (ISO) guideline 14044 indicates that economic allocation should only be used as a last resort, when other methods are not suitable. However, the LCA literature reports several examples of the use of economic allocation. This is due partly to its simplicity and partly to its ability to illustrate the properties of complex systems. Sometimes a price summarizes complex attributes of product or service quality that cannot be easily measured by physical criteria. On the other hand, economic allocation does have limitations arising, for example, from the variability of prices and the low correlation between prices and physical flows. This article presents the state of the debate on the topic and some hypothetical examples for illustration. A general conclusion is that it is not possible to determine one “best” allocation method. The allocation procedure has to be selected on a case‐by‐case basis and no single approach is suitable for every situation. Despite its limitations, economic allocation has certain qualities that make it flexible and potentially suitable for different contexts. In some situations, economic allocation should not be the last methodological resort. The option of economic allocation should be considered, for example, whenever the prices of coproducts and coservices differ widely.     

Life Cycle Assessment of Water Supply Plans in Mediterranean Spain

Life cycle assessment (LCA) was used to compare the current water supply planning in Mediterranean Spain, the so‐called AGUA Programme, with its predecessor, the Ebro river water transfer (ERWT). Whereas the ERWT was based on a single interbasin transfer, the AGUA Programme excludes new transfers and focuses instead on different types of resources, including seawater and brackish water desalination and wastewater reuse, among others. The study includes not only water supply but the whole anthropic cycle of water, from water abstraction to wastewater treatment. In addition to standard LCA impact categories, a specific impact category focusing on freshwater resources is included, which takes into account freshwater scarcity in the affected water catchments. In most impact categories the AGUA Programme obtains similar or even lower impact scores than ERWT. Concerning impacts on freshwater resources, the AGUA Programme obtains an impact score 49% lower than the ERWT. Although the current water planning appears to perform better in many impact categories than its predecessor, this study shows that water supply in Spanish Mediterranean regions is substantially increasing its energy intensity and that Mediterranean basins suffer a very high level of water stress due to increasing demand and limited resources.     

Using the Lashof Accounting Methodology to Assess Carbon Mitigation Projects With Life Cycle Assessment

As governments elaborate strategies to counter climate change, there is a need to compare the different options available on an environmental basis. This study proposes a life cycle assessment framework integrating the Lashof accounting methodology, which enables the assessment and comparison of different carbon mitigation projects (e.g., biofuel use, a sequestering plant, an afforestation project). The Lashof accounting methodology is chosen amid other methods of greenhouse gas (GHG) emission characterization for its relative simplicity and capability to characterize all types of carbon mitigation projects. Using the unit of megagram‐year (Mg‐year), which accounts for the mass of GHGs in the atmosphere multiplied by the time it stays there, the methodology calculates the cumulative radiative forcing caused by GHG emission within a predetermined time frame. Basically, the developed framework uses the Mg‐year as a functional unit and isolates impacts related to the climate mitigation function with system expansion. The proposed framework is demonstrated with a case study of tree ethanol pathways (maize, sugarcane, and willow). The study shows that carbon mitigation assessment through life cycle assessment is possible and that it could be a useful tool for decision makers, as it can compare different projects regardless of their original context. The case study reveals that system expansion, as well as each carbon mitigation project's efficiency at reducing carbon emissions, are critical factors that have a significant impact on the results. Also, the framework proves to be useful for treating land‐use change emissions, as they are considered through the functional unit.     

Value Choices in Life Cycle Impact Assessment of Stressors Causing Human Health Damage

This article investigates how value choices in life cycle impact assessment can influence characterization factors (CFs) for human health (expressed as disability‐adjusted life years [DALYs]). The Cultural Theory is used to define sets of value choices in the calculation of CFs, reflecting the individualist, hierarchist, and egalitarian perspectives. CFs were calculated for interventions related to the following impact categories: water scarcity, tropospheric ozone formation, particulate matter formation, human toxicity, ionizing radiation, stratospheric ozone depletion, and climate change. With the Cultural Theory as a framework, we show that individualist, hierarchist, and egalitarian perspectives can lead to CFs that vary up to six orders of magnitude. For persistent substances, the choice in time horizon explains the differences among perspectives, whereas for nonpersistent substances, the choice in age weighting and discount rate of DALY and the type of effects or exposure routes account for differences in CFs. The calculated global impact varies by two orders of magnitude, depending on the perspective selected, and derives mainly from particulate matter formation and water scarcity for the individualist perspective and from climate change for the egalitarian perspective. Our results stress the importance of dealing with value choices in life cycle impact assessment and suggest further research for analyzing the practical consequences for life cycle assessment results.     

Life Cycle Assessment of Medium Surge Arresters in the Context of Size‐Reduction Design

Zinc oxide (ZnO) polycrystalline ceramics are the focal point of lightning arrester technology. These semiconductor materials are able to switch rapidly from high to low impedance while handling large amounts of electrical energy. Since the early 1970s, considerable efforts have been made to improve the specific energy absorption capacity and device reliability of such components. This document describes a case study carried out on the life cycle impacts of three different designs of electroceramics made of ZnO. Results show that the best design involves decreasing the diameter while maintaining the thickness of the compound. Of the production, transport, use, and end‐of‐life phases, the use phase is found to contribute by far the most to environmental impacts, with leakage currents in the 10^?6 ampere range. The next‐largest impacts come in the transport and production stages. Sensitivity analysis shows that impacts associated with the production stage originate from ZnO production and are related to the by‐products (heavy metals) of zinc metallurgy.     

Informing Packaging Design Decisions at Toyota Motor Sales Using Life Cycle Assessment and Costing

Throughout their life cycle stages—material production, package manufacture, distribution, end-of-life management—packaging systems consume natural resources and energy, generate waste, and emit pollutants. Each of these stages also carries a financial cost. Motivated by a desire to decrease environmental burdens while reducing financial costs associated with the packaging of accessory and service parts, Toyota Motor Sales (TMS) partnered with the Donald Bren School of Environmental Science & Management to build a life cycle assessment and costing tool to support packaging design decisions. The resulting Environmental Packaging Impact Calculator (EPIC) provides comprehensive life cycle assessment (LCA) and life cycle costing (LCC). It allows packaging designers to identify environmentally and economically preferable packaging systems in daily decision-making. EPIC's parameterized process flow model allows users to assess many different packaging systems using a single model. Its input/output interface is designed for users without preexisting knowledge of LCA theory or practice and calculates results based on relatively few input data. The main motivation behind this environmental design tool is to provide relevant information to those individuals who are in the best position to reduce life cycle impacts and costs from TMS's packaging and distribution systems.     

Improvements in Life Cycle Energy Efficiency and Greenhouse Gas Emissions of Corn-Ethanol

Corn-ethanol production is expanding rapidly with the adoption of improved technologies to increase energy efficiency and profitability in crop production, ethanol conversion, and coproduct use. Life cycle assessment can evaluate the impact of these changes on environmental performance metrics. To this end, we analyzed the life cycles of corn-ethanol systems accounting for the majority of U.S. capacity to estimate greenhouse gas (GHG) emissions and energy efficiencies on the basis of updated values for crop management and yields, biorefinery operation, and coproduct utilization. Direct-effect GHG emissions were estimated to be equivalent to a 48% to 59% reduction compared to gasoline, a twofold to threefold greater reduction than reported in previous studies. Ethanol-to-petroleum output/input ratios ranged from 10:1 to 13:1 but could be increased to 19:1 if farmers adopted high-yield progressive crop and soil management practices. An advanced closed-loop biorefinery with anaerobic digestion reduced GHG emissions by 67% and increased the net energy ratio to 2.2, from 1.5 to 1.8 for the most common systems. Such improved technologies have the potential to move corn-ethanol closer to the hypothetical performance of cellulosic biofuels. Likewise, the larger GHG reductions estimated in this study allow a greater buffer for inclusion of indirect-effect land-use change emissions while still meeting regulatory GHG reduction targets. These results suggest that corn-ethanol systems have substantially greater potential to mitigate GHG emissions and reduce dependence on imported petroleum for transportation fuels than reported previously.     

Life Cycle Sustainability Dashboard

One method to assess the sustainability performance of products is life cycle sustainability assessment (LCSA), which assesses product performance considering the environmental, economic, and social dimensions of the life cycle. The results of LCSA can be used to compare different products or to support decision making toward sustainable production and consumption. In both cases, LCSA results could be too disaggregated and consequently too difficult to understand and interpret by decision makers. As non‐experts are usually the target audience of experts and scientists, and are also involved in decision‐making processes, the necessity for a straightforward but comprehensive presentation of LCSA results is becoming strategically important. The implementation of the dashboard of sustainability proposed in this article offers a possible solution. An outstanding characteristic of the dashboard of sustainability is the communicability of the results by means of a graphical representation (a cartogram), characterized by a suitable chromatic scale and ranking score. The integration of LCSA and the dashboard of sustainability into a so‐called Life Cycle Sustainability Dashboard (LCSD) is described here. The first application of LCSD to a group of hard floor coverings is presented to show the applicability and limitations of the methodology.     

Life Cycle of Titanium Dioxide Nanoparticle Production

Life cycle impact of emissions, energy requirements, and exergetic losses are calculated for a novel process for producing titanium dioxide nanoparticles from an ilmenite feedstock. The Altairnano hydrochloride process analyzed is tailored for the production of nanoscale particles, unlike established commercial processes. The life cycle energy requirements for the production of these particles is compared with that of traditional building materials on a per unit mass basis. The environmental impact assessment and energy analysis results both emphasize the use of nonrenewable fossil fuels in the upstream life cycle. Exergy analysis shows fuel losses to be secondary to material losses, particularly in the mining of ilmenite ore. These analyses are based on the same inventory data. The main contributions of this work are to provide life cycle inventory of a nanomanufacturing process and reveal potential insights from exergy analysis that are not available from other methods.     

Life Cycle Greenhouse Gas Emissions Reduction From Rigid Thermal Insulation Use in Buildings

Thermal insulation is a strategic product for reducing energy consumption and related greenhouse gas (GHG) emissions from the building sector. This study examines from a life cycle perspective the changes in GHG emissions resulting from the use of two rigid thermal insulation products manufactured and installed from 1971 to 2025. GHG emissions related to insulation production and fugitive releases of blowing agents are modeled and compared with GHG savings from reduced heating loads in North America, Europe, and Asia. Implementation of alternative blowing agents has greatly improved the carbon dioxide 100‐year equivalent (CO₂‐eq) emission performance of thermal insulation. The net average CO₂‐eq savings to emissions ratio for current extruded polystyrene (XPS) and polyisocyanurate (PIR) insulation studied was 48:1, with a broad range from 3 to 1,800. Older insulation products manufactured with chlorofluorocarbons (CFCs) can result in net cumulative GHG emissions. Reduction of CO₂‐eq emissions from buildings is governed by complex interactions between insulation thickness and placement, climate, fuel type, and heating system efficiencies. A series of charts mapping both emissions payback and net savings demonstrate the interactions between these factors and provide a basis for specific policy recommendations to guide effective insulation investments and placement.