Provision of LCI data in the European aluminium industry Methods and examples

Background, aim, and scope

The development of robust and up-to-date generic life cycle inventory data for materials is absolutely crucial for the LCA community since many LCA studies rely on these generic data about materials. LCA databases and software usually include within their package such generic LCI datasets. However, in many cases, the quality of these data is poor while the methodology and the models used for their development are rarely accessible or transparent. This paper presents the development of robust European LCI datasets for the production of primary and recycled aluminium ingots and for the transformation of aluminium ingot into semi-finished products, i.e. sheet, foil and extrusion.

Materials and methods

The environmental data have been collected through an extensive environmental survey, organised among the European aluminium industry, focusing on the year 2005 and covering EU27 countries as well as EFTA countries (Norway, Iceland and Switzerland). From this survey, European averages, i.e. foreground data, have been calculated for the direct inputs and outputs of the various aluminium processes. Using the GaBi software, the foreground data have been combined within LCI models integrating background LCI data on energy supply systems, ancillary processes and materials. For the primary aluminium production (smelters), a specific model for the electricity production has been developed. The methodology for the data consolidation and for the development of the various models is explained as well as the main differences between the new modelling approach and LCI models used in the past. An independent expert has critically reviewed the entire LCI project including data collection, models development, calculation of LCI data and associated environmental indicators.

Results

As confirmed by the critical review, the new LCI datasets for aluminium ingot production and transformation into semi-finished products have been developed though a robust methodology in full accordance with ISO 14040 and 14044. Most significant environmental data and LCI results are reported in this paper with an emphasis on energy use and the major emissions to air. The full environmental report, including the critical review report and the calculation of environmental indicators for a pre-set of impact categories, is available on the website of the European Aluminium Association (EAA 2008). Whenever possible, the updated European averages and the new LCI data are compared with previous results developed from two past European surveys covering respectively the years 2002 and 1998. For the aluminium processes related to primary production, European averages are also benchmarked against global averages calculated from two worldwide surveys covering the years 2000 and 2005.

Discussion

While some data evolutions are directly attributed to the variation of foreground data, e.g. raw materials consumption or energy use within the aluminium processes, modifications related to the system boundaries, the background data and the modelling hypotheses can also influence significantly the LCI results. For primary aluminium production, the evolution of the foreground data is dominated by the strong decrease of PFC (perfluorocarbon) emissions (about 70% since 1998). In addition, the electricity structure calculated from the refined electricity model shows significant differences compared to previous models. In the 2005 electricity model, the hydropower share reaches 58% while coal contributes to 15% only of the electricity production. In 1998, the respective share of coal-based and hydro-electricity were respectively calculated to 25% and 52%. As a result, the electricity background LCI data are then significantly affected and influence also positively the environmental profile of primary aluminium in Europe. For the semi-production processes, the reduction of process scrap production, especially for extrusion and foil, demonstrates the increase of process efficiency from 1998. In parallel, a significant reduction of energy use is observed between 1998 and 2005. However, this positive trend is not fully reflected within LCI data due to the significant contribution of the background electricity data. The choice of the electricity model plays also a critical role for these transformation processes since electricity production contributes to about 2/3 of the consumption of the non-renewable energy and to about the same level of the air emissions. In such a case, the move from the UCPTE electricity model used in the past towards the EU25 electricity model used for the development of the updated LCI data has a detrimental effect on the environmental profile of the three LCI datasets respectively related to sheet, foil and extrusion. In addition to energy and process scrap reduction, the reduction of the VOC (volatile organic compounds) emission is also a major trend in foil production. Finally, for old aluminium scrap recycling, the new LCI data show a dramatic improvement regarding energy efficiency, reinforcing the environmental soundness of promoting and supporting aluminium recycling within the aluminium product life cycles.

Conclusions

This paper shows the development of generic LCI data about aluminium production and transformation processes which are based on robust data, methodologies and models in full accordance with ISO 14040 and 14044 standards, as confirmed by the critical review. The publishing of these LCI datasets definitely shows the commitment of the European aluminium industry to contribute in a transparent, fair and scientifically sound manner to product sustainability in a life cycle thinking perspective.

Recommendations and perspectives

Software houses and LCA practitioners are invited to update their generic European data on aluminium with the herewith datasets. Even if the quality and the completeness of these LCI data reach a high standard, some areas for data improvements have been identified, as described within the review report. Land use, water use and solid waste treatment appear as three priority areas for data refining and improvement. The land use dimension, particularly meaningful for bauxite mining, is not covered in the current LCI data while it is now integrated within many LCA studies. Up to now, the reporting of meaningful and robust data on water origins and use have not been possible due to the huge discrepancies between the surveyed sites combined with the difficulty to report coherent input and output water mass flows. The development of water data, only focussing on water-stressed areas, will most probably make more sense in the future. Finally, collecting more qualitative information about solid waste processing and treatment will help to include such operations within the system boundaries and to model their associated air, water and soil emissions.

     

Life Cycle Assessment for Emerging Technologies: Case Studies for Photovoltaic and Wind Power (11 pp)

Goal, Scope and Background This paper describes the modelling of two emerging electricity systems based on renewable energy: photovoltaic (PV) and wind power. The paper shows the approach used in the ecoinvent database for multi-output processes.Methods Twelve different, grid-connected photovoltaic systems were studied for the situation in Switzerland. They are manufactured as panels or laminates, from mono- or polycrystalline silicon, installed on facades, slanted or flat roofs, and have a 3kWp capacity. The process data include quartz reduction, silicon purification, wafer, panel and laminate production, supporting structure and dismantling. The assumed operational lifetime is 30 years. Country-specific electricity mixes have been considered in the LCI in order to reflect the present situation for individual production stages. The assessment of wind power includes four different wind turbines with power rates between 30 kW and 800 kW operating in Switzerland and two wind turbines assumed representative for European conditions – 800 kW onshore and 2 MW offshore. The inventory takes into account the construction of the plants including the connection to the electric grid and the actual wind conditions at each site in Switzerland. Average European capacity factors have been assumed for the European plants. Eventually necessary backup electricity systems are not included in the analysis.Results and Discussion The life cycle inventory analysis for photovoltaic power shows that each production stage may be important for specific elementary flows. A life cycle impact assessment (LCIA) shows that there are important environmental impacts not directly related to the energy use (e.g. process emissions of NOx from wafer etching). The assumption for the used supply energy mixes is important for the overall LCIA results of different production stages. The allocation of the inventory for silicon purification to different products is discussed here to illustrate how allocation has been implemented in ecoinvent. Material consumption for the main parts of the wind turbines gives the dominant contributions to the cumulative results for electricity production. The complex installation of offshore turbines, with high requirements of concrete for the foundation and the assumption of a shorter lifetime compared to onshore foundations, compensate the advantage of increased offshore wind speeds.Conclusion The life cycle inventories for photovoltaic power plants are representative for newly constructed plants and for the average photovoltaic mix in Switzerland in the year 2000. A scenario for a future technology helps to assess the relative influence of technology improvements for some processes in the near future (2005-2010). The differences for environmental burdens of wind power basically depend upon the capacity factor of the plants, the lifetime of the infrastructure, and the rated power. The higher these factors, the more reduced the environmental burdens are. Thus, both systems are quite dependent on meteorological conditions and the materials used for the infrastructure.Recommendation and Perspective Many production processes for photovoltaic power are still under development. Future updates of the LCI should verify the energy uses and emissions with available data from industrial processes in operation. For the modelling of a specific power plant or power plant mixes outside of Switzerland, one has to consider the annual yield (kWh/kWp) and if possible also the size of the plant. Considering the steady growth of the size of wind turbines in Europe, the development of new designs, and the exploitation of offshore location with deeper waters than analysed in this study, the inventory for wind power plants may need to be updated in the future.     

Life cycle inventory analysis of granite production from cradle to gate

Purpose

Granite is a traditional high-quality material that is widely used in construction. A key strategy that is increasingly promoted to highlight the competitiveness of materials is life cycle environmental performance. Due to the lack of comprehensive life cycle inventories (LCIs), the environmental characterisation of granite products has received little attention in scientific literature. In this paper, a complete LCI of the production chain of intermediate and finished granite products is provided and analysed.

Methods

The Spanish granite production industry, which is the second major European producer and the seventh worldwide, is examined. The reference unit is defined as 1 m² of finished granite tiles with dimensions 60?×?40?×?2 cm used for indoor and outdoor applications. Input and output data were collected through the distribution of technical data collection surveys to quarries and processing facilities and via on-site visits. During data calculation and validation, technical support was provided by technicians from the Spanish Cluster of Granite Producers. The LCI data describe the industrial activity in baseline year 2010 that corresponds to a total production volume of 48,052 m³ of quarried granite and a net of 881,406 m² of processed granite.

Results and discussion

The production of 1 m² of polished granite tiles requires 28 kWh of electricity, 23 MJ of diesel, 103 l of water, and 7 kg of ancillary materials. Sandblasted, flamed or bush-hammered finishes applied to granite tiles have a minimal effect on their total energy and material requirements but significantly affect their water consumption. Electrical energy, cooling water and steel are the major industrial requirements in which granite sawing is the most demanding process. The resource efficiency of the production chain is 0.31. Approximately 117 kg of granite are wasted per square meter of granite tiles that are produced (53 kg). Seventy-four percent of granite waste is composed of granite scrap, which becomes a marketable by-product. The predominant source of granite waste is the sawdust that is generated during stone-cutting operations.

Conclusions

LCIs provide the relevant information required to characterise the environmental performance of granite production and products. LCI data can be easily managed by users due to the disaggregation into unit processes. LCI data can be used to analyse the environmental burden associated with intermediary granite products, such as granite blocks, sawn granite slabs and finished granite slabs, and to analyse the environmental burden of finished granite tiles according to the corresponding net production volumes.

Recommendations

LCI dataset of granite production should be extended to include alternative production technologies, such as diamond multiwire machines for sawing granite, which is an increasingly competitive production technology with interesting properties for cleaner production. Strong competitive granite industries, such as the industries in China, India and Brazil, should also provide LCIs of granite products to transparently compare different product chains, identify environmental strategies on the sector level, and promote the green procurement of granite products.     

The Glasgow consensus on the delineation between pesticide emission inventory and impact assessment for LCA

Purpose

Pesticides are applied to agricultural fields to optimise crop yield and their global use is substantial. Their consideration in life cycle assessment (LCA) is affected by important inconsistencies between the emission inventory and impact assessment phases of LCA. A clear definition of the delineation between the product system model (life cycle inventory—LCI, technosphere) and the natural environment (life cycle impact assessment—LCIA, ecosphere) is missing and could be established via consensus building.

Methods

A workshop held in 2013 in Glasgow, UK, had the goal of establishing consensus and creating clear guidelines in the following topics: (1) boundary between emission inventory and impact characterisation model, (2) spatial dimensions and the time periods assumed for the application of substances to open agricultural fields or in greenhouses and (3) emissions to the natural environment and their potential impacts. More than 30 specialists in agrifood LCI, LCIA, risk assessment and ecotoxicology, representing industry, government and academia from 15 countries and four continents, met to discuss and reach consensus. The resulting guidelines target LCA practitioners, data (base) and characterisation method developers, and decision makers.

Results and discussion

The focus was on defining a clear interface between LCI and LCIA, capable of supporting any goal and scope requirements while avoiding double counting or exclusion of important emission flows/impacts. Consensus was reached accordingly on distinct sets of recommendations for LCI and LCIA, respectively, recommending, for example, that buffer zones should be considered as part of the crop production system and the change in yield be considered. While the spatial dimensions of the field were not fixed, the temporal boundary between dynamic LCI fate modelling and steady-state LCIA fate modelling needs to be defined.

Conclusions and recommendations

For pesticide application, the inventory should report pesticide identification, crop, mass applied per active ingredient, application method or formulation type, presence of buffer zones, location/country, application time before harvest and crop growth stage during application, adherence with Good Agricultural Practice, and whether the field is considered part of the technosphere or the ecosphere. Additionally, emission fractions to environmental media on-field and off-field should be reported. For LCIA, the directly concerned impact categories and a list of relevant fate and exposure processes were identified. Next steps were identified: (1) establishing default emission fractions to environmental media for integration into LCI databases and (2) interaction among impact model developers to extend current methods with new elements/processes mentioned in the recommendations.

     

Assessing Socioeconomic Metabolism Through Hybrid Life Cycle Assessment

This article applies a combined input−output and life cycle inventory (LCI) method to the calculation of emissions and material requirements of the Czech economy in 2003. The main focus is on materials and emissions embodied in the international trade of the Czech Republic. Emissions and material extraction avoided due to imports are calculated according to an input−output approach that assumes the same production technology for imports as for domestic production. Because not all products are provided by the domestic economy, the LCI data are incorporated into the monetary input−output model.
The results show that incorporating the LCI data into an input−output model is reasonable. The emissions embodied in the international trade of the Czech Republic are comparable to the domestic emissions. We compare the economy-wide material flow indicators, such as direct material input, domestic material consumption, and physical trade balance, to their raw material equivalents. The results of our calculation show that the Czech Republic exerts environmental pressure on the environment in other countries through international trade.
We argue that raw material equivalents should be used to express the flows across national boundaries. Furthermore, we recommend a raw material consumption indicator for international comparisons.     

A spatially explicit life cycle inventory of the global textile chain

Background, aim, and scope  Life cycle analyses (LCA) approaches require adaptation to reflect the increasing delocalization of production to emerging countries. This work addresses this challenge by establishing a country-level, spatially explicit life cycle inventory (LCI). This study comprises three separate dimensions. The first dimension is spatial: processes and emissions are allocated to the country in which they take place and modeled to take into account local factors. Emerging economies China and India are the location of production, the consumption occurs in Germany, an Organisation for Economic Cooperation and Development country. The second dimension is the product level: we consider two distinct textile garments, a cotton T-shirt and a polyester jacket, in order to highlight potential differences in the production and use phases. The third dimension is the inventory composition: we track CO₂, SO₂, NO _x , and particulates, four major atmospheric pollutants, as well as energy use. This third dimension enriches the analysis of the spatial differentiation (first dimension) and distinct products (second dimension). Materials and methods  We describe the textile production and use processes and define a functional unit for a garment. We then model important processes using a hierarchy of preferential data sources. We place special emphasis on the modeling of the principal local energy processes: electricity and transport in emerging countries. Results  The spatially explicit inventory is disaggregated by country of location of the emissions and analyzed according to the dimensions of the study: location, product, and pollutant. The inventory shows striking differences between the two products considered as well as between the different pollutants considered. For the T-shirt, over 70% of the energy use and CO₂ emissions occur in the consuming country, whereas for the jacket, more than 70% occur in the producing country. This reversal of proportions is due to differences in the use phase of the garments. For SO₂, in contrast, over two thirds of the emissions occur in the country of production for both T-shirt and jacket. The difference in emission patterns between CO₂ and SO₂ is due to local electricity processes, justifying our emphasis on local energy infrastructure. Discussion  The complexity of considering differences in location, product, and pollutant is rewarded by a much richer understanding of a global production–consumption chain. The inclusion of two different products in the LCI highlights the importance of the definition of a product's functional unit in the analysis and implications of results. Several use-phase scenarios demonstrate the importance of consumer behavior over equipment efficiency. The spatial emission patterns of the different pollutants allow us to understand the role of various energy infrastructure elements. The emission patterns furthermore inform the debate on the Environmental Kuznets Curve, which applies only to pollutants which can be easily filtered and does not take into account the effects of production displacement. We also discuss the appropriateness and limitations of applying the LCA methodology in a global context, especially in developing countries. Conclusions  Our spatial LCI method yields important insights in the quantity and pattern of emissions due to different product life cycle stages, dependent on the local technology, emphasizing the importance of consumer behavior. From a life cycle perspective, consumer education promoting air-drying and cool washing is more important than efficient appliances. Recommendations and perspectives  Spatial LCI with country-specific data is a promising method, necessary for the challenges of globalized production–consumption chains. We recommend inventory reporting of final energy forms, such as electricity, and modular LCA databases, which would allow the easy modification of underlying energy infrastructure. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Wrapping Up Greenhouse Gas Emissions An Assessment of GHG Emission Reduction Related to Efficient Packaging Use: An Assessment of GHG Emission Reduction Related to Efficient Packaging Use

The use of packaging materials results in greenhouse gas (GHG) emissions through production and transport of materials and packaging and through end-of-life management. In this article, we investigate the potential reduction of GHGs that are related to packaging. For this purpose, we use the dynamic MATTER-MARKAL model in which the western European energy and materials system is modeled. The results show that GHGs related to packaging can technically be reduced by up to 58% in the period 1995–2030. Current European packaging directives will result in a 10% emission reduction. Cost-effective improved material management 1 that includes lightweighting, reusable packages, material recycling, and related strategies can contribute a 22% GHG emission reduction. An additional 13% reduction becomes cost effective when a GHG emission penalty of 100 euros per metric ton 2 (EUR/ton) is introduced (1 EUR 0.9 USD). Generally speaking, improved material management dominates the gains that can be achieved without a penalty or with low GHG emission penalties (up to 100 EUR/ton CO2 equivalent). By contrast, the reduction of emissions in materials production and waste handling dominate when high GHG penalties are applied (between 100 and 500 EUR/ton CO2 equivalent). Given the significant technical potential and the low costs, more attention should be paid to material efficiency improvement in GHG emission reduction strategies.     

Methodology for developing gate-to-gate Life cycle inventory information

Life Cycle Assessment (LCA) methodology evaluates holistically the environmental consequences of a product system or activity, by quantifying the energy and materials used, the wastes released to the environment, and assessing the environmental impacts of those energy, materials and wastes. Despite the international focus on environmental impact and LCA, the quality of the underlying life cycle inventory data is at least as, if not more, important than the more qualitative LCA process. This work presents an option to generate gate-to-gate life cycle information of chemical substances, based on a transparent methodology of chemical engineering process design (an ab initio approach). In the broader concept of a Life Cycle Inventory (LCI), the information of each gate-to-gate module can be linked accordingly in a production chain, including the extraction of raw materials, transportation, disposal, reuse, etc. to provide a full cradle to gate evaluation. The goal of this article is to explain the methodology rather than to provide a tutorial on the techniques used. This methodology aims to help the LCA practitioner to obtain a fair and transparent estimate of LCI data when the information is not readily available from industry or literature. Results of gate-to-gate life cycle information generated using the cited methodology are presented as a case study. It has been our experience that both LCI and LCA information provide valuable means of understanding the net environmental consequence of any technology. The LCI information from this methodology can be used more directly in exploring engineering and chemistry changes to improve manufacturing processes. The LCA information can be used to set broader policy and to look at more macro improvements for the environment.     

Life cycle inventory processes of the ArcelorMittal Poland (AMP) S.A. in Kraków,Poland—basic oxygen furnace steel production

Purpose  

The goal of this paper is to describe the life cycle inventory (LCI) approach to steel produced by ArcelorMittal’s Basic Oxygen Furnace (AMBOF) in Kraków, Poland. The present LCI is representative for the reference year 2005 by application of PN-EN ISO 14040:2009 (PN-EN ISO 2009). The system boundaries were labeled as gate-to-gate (covering a full chain process of steel production). The background input and output data from the basic oxygen furnace (BOF) steelmaking process has been inventoried as follows: pig iron, scrap, slag forming materials (CaO), ferroalloys, Al, carbon and graphite carburizer (material for carburization of steel), isolating powder, consumption of energy and fuels including natural gas, blast furnace gas and coke oven gas, electric energy, steam, air, oxygen, industrial water and heat, emission of air pollutants, waste, internal transport and land use.     

Ambiguities in decision-oriented Life Cycle Inventories The Role of mental models

If the complexity of real, socio-economic systems is acknowledged, life cycle inventory analysis (LCI) in life cycle assessment (LCA) cannot be considered as unambiguous, objective, and as an exclusively data and science based attribution of material and energy flows to a product. The paper thus suggests a set of criteria for LCI derived from different scientific disciplines, practice of product design and modelling characteristics of LCI and LCA. A product system with its respective LCI supporting the process of effective and efficient decision-making should ideally be: a) complete, operational, decomposable, non-redundant, minimal, and comparable; b) efficient, i.e., as simple, manageable, transparent, cheap, quick, but still as ‘adequate’ as possible under a functionalistic perspective which takes given economic constraints, material and market characteristics, and the goal and scope of the study into account; c) actor-based when reflecting the decision-makers’ action space, risk-level, values, and knowledge (i.e. mental model) in view of the management rules of sustainable development; d) as site- and case-specific as possible, i.e. uses as much site-specific information as possible. This rationale stresses the significance of considering both (i) material and energy flows within the technosphere with regard to the sustainable management rules; (ii) environmental consequences of the environmental interventions on ecosphere. Further, the marginal cost of collecting and computing more and better information about environmental impacts must not exceed the marginal benefits of information for the natural environment. The ratio of environmental benefits to the economic cost of the tool must be efficient compared to other investment options. As a conclusion, in comparative LCAs, the application of equal allocation procedures does not lead to LCA-results on which products made from different materials can be compared in an adequate way. Each product and material must be modelled according to its specific material and market characteristics as well as to its particular management rules for their sustainable use. A generic LCA-methodology including preferences on methodological options is not definable.     

Influence of derived operation-specific tractor emission data on results from an LCI on wheat production

The shortage of data for emissions from agricultural tractors contributes to LCA results on environmental load from modern crop production possibly having high error levels and high uncertainties. The first part of this work describes measurements and calculations made in order to obtain operation-specific agricultural emission data. Calculations are based on emission data measured on a standard 70 kW tractor of a widely available make. In the second part, results from an LCI on wheat production based on traditionally used emission data are calculated and compared with results obtained when using the emission data for specific working operations derived in part one. One conclusion of the study is that the emission values, when related to the energy in the used fuel, show very large variations between different driving operations. Another conclusion is that the use of the new data results in a marked reduction of the total air emissions produced in the wheat production chain, especially for CO and HC, but also for NO_x and SO₂.     

Life cycle inventory of energy production in ArcelorMittal steel power plant Poland S.A. in Krakow,Poland

Purpose  

The goal of this paper is to describe the life cycle inventory (LCI) approach of energy produced by ArcelorMittal Steel Power Plant Poland (AMSPPP) in Krakow, Poland. The present LCI is representative for the reference year 2005 by application of ISO 14040: 2006. The system boundaries were labeled as gate-to-gate (it covered full process chain for energy production). Background data of inputs and outputs from the steel power plant have been inventoried as follows: consumption of energy and fuels, including: power coal (domestic), natural gas, blast furnace gas and coke oven gas, emission of air pollutants, emissions of particulate, air emissions from stockpiles, wastes, internal transport, and land use.     

Life cycle inventory processes of the Mittal Steel Poland (MSP) S.A. in Krakow, Poland—blast furnace pig iron production—a case study

Purpose

The goal of this paper is to describe the life cycle inventory (LCI) approach of pig iron produced by Mittal??s Steel Poland Blast Furnace (MSPBF) in Krakow, Poland. The present LCI is representative for the reference year 2005 by application of PN-EN ISO 14040: 2009 (PN-EN ISO 2009). The system boundaries were labeled as gate-to-gate (covering a full chain process of pig iron production). The background input and output data from the blast furnace (BF) process have been inventoried as follows: sinter, several types of pellets, ore (from Brazil or Venezuela), limestone, coke, and from 2005 coal powder, pig iron, blast furnace gas, blast furnace slug, consumption of energy and fuels, including: pulverized coal, natural gas, blast furnace gas and coke oven gas, and emission of air pollutants.

Main feature

LCI energy generation was developed mainly on the basis of following sources: site specific measured or calculated data, study carried out by Mittal Steel Poland (MSP) Environmental Impact Report, study carried out by the Faculty of Mining Surveying and Environmental Engineering of the AGH University of Science and Technology in Krakow, literature information, and expert consultations. The functional unit is represented by 1,504,088?Mg of pig iron, produced BF process. Time coverage is 2005. Operating parameters as well as air emissions associated with the BF process were presented. The production data (pig iron) was given. The emissions of SO₂, NO₂, CO, CO₂, aliphatic hydrocarbons, dust, heavy metals (Cr, Cd, Cu, Pb, Ni, and Mn), and waste are the most important outcomes of the pig iron process.

Results

With regard to 1,504,088?Mg of pig iron produced by MSP, the consumption of coke, pulverized coal, sinters, pellets, and natural gas were 808,509, 16,921, 1,669,023, and 914,080?Mg, respectively. Other material consumption, industrial water, was 1,401,419 m³/year.

Conclusions

The LCI study is the first tentative study to express pig iron production in Poland in terms of LCA/LCI for the pig iron in steel industry. The results may help steel industry government make decisions in policy making. Presentation of the study in this paper is suitable for the other industries.

Recommendations and outlook

The LCI offers environmental information consisting on the list of environmental loads. The impact assessment phase aims the results from the inventory analysis more understandable and life cycle impact assessment will be direction for future research. Another issue to discuss is integration of LCA and risk assessment for industrial processed.     

Saving Energy versus Saving Materials

To reduce energy consumption and carbon dioxide (CO₂) emissions in housing construction, the energy-intensive processes and life-cycle stages should be identified and integrated. The environmental impact of vertically integrated factory-built homes (VIHs) constructed with increased material inputs in Japan's northern island of Hokkaido was assessed using life-cycle inventory (LCI) analysis methods. Manufacturing process energy and CO₂ intensities of the homes were evaluated based on the material inputs. They were compared with those of a counterpart home hypothetically built using the vertically integrated construction methods, but in accordance with the specifications of a less material-intensive conventional home (CH) in Hokkaido today. Cumulative household energy consumption and CO₂ emissions were evaluated and compared with those of the production stages. The annual household energy consumption was compared among a VIH, a CH, and an average home in Hokkaido. The energy intensity of the VIH was 3.9 GJ production energy per m² of floor area, 59% higher than that of the CH. Net CO₂ emissions during VIH manufacturing processes were 293 kg/m², after discounting the carbon fixation during tree growth. The cumulative use-phase household energy consumption and CO₂ emissions of a VIH will exceed energy consumption and CO₂ emissions during the initial production stage in less than six years. Although VIHs housed 21% more residents on average, the energy consumption per m2 was 17% lower than that of a CH. This may indicate that using more materials initially can lead to better energy efficiency.     

Life cycle assessment for the implementation of emission control measures for the freight traffic with heavy duty vehicles in Germany

Under consideration of the overall Life Cycle Inventory Analysis (LCI) results generated in the first step of this study and based on the February 1999 edition of ISO/DIS 14042 the Life Cycle Impact Assessment (LCIA) for the introduction of various emission control measures for freight traffic heavy duty vehicles in Germany was determined. For the examination of the several mandatory elements 11 impact categories related to the freight traffic and the LCI results were focussed, the LCI results were designed to these impact categories and with characterization factors of the 11 selected and recognized characterisation models the categories indicator endpoints were quantified. The optional elements for normalization and weighting were added to the analysis. Two reference values are used for normalizing the category indicator results. For the weighting step 8 recognized evaluation methods were selected with the aim to aggregate the LCI results to an overall value. The results enable plausible conclusions with regard to the ecological advantages and disadvantages of the use of each analysed emission control technology for heavy duty diesel vehicles. As no perfectly clear ranking can be distinguished for evaluation of the generated results and no correlation can be established to the economical effects of the corresponding measurements, it is necessary to complete the currently existing recommendation from the ISO/DIS-Standards with further parameters. Phase 1: Life Cycle Inventory Analysis. Int J LCA vn6 (4) 231–242(2001) Phase 3: Life Cycle Interpretation (DOI: http://dx.doi.oro/10.1065/ Ica2000.12.044.3)     

Life Cycle Inventory Information of the United States Electricity System (11/17 pp)

Goal and Scope This study estimates the life cycle inventory (LCI) of the electricity system in the United States, including the 10 NERC (North American Electric Reliability Council) regions, Alaska, Hawaii, off-grid non-utility plants and the US average figures. The greenhouse gas emissions associated with the United States electricity system are also estimated. Methods The fuel mix of the electricity system based on year 2000 data is used. The environmental burdens associated with raw material extraction, petroleum oil production and transportation for petroleum oil and natural gas to power plants are adopted from the DEAMTM LCA database. Coal transportation from a mining site to a power plant is specified with the data from the Energy Information Administration (EIA), which includes the mode of transportation as well as the distance traveled. The gate-to-gate environmental burdens associated with generating electricity from a fossil-fired power plant are obtained from the DEAMTM LCA database and the eGRID model developed by the United States Environmental Protection Agency. For nuclear power plants and hydroelectric power plants, the data from the DEAMTM LCA database are used.Results and Discussion Selected environmental profiles of the US electricity system are presented in the paper version, while the on-line version presents the whole LCI data. The overall US electricity system in the year 2000 released about 2,654 Tg CO2 eq. of greenhouse gas emissions based on 100-year global warming potentials with 193 g CO2 eq. MJe–1 as an weighted average emission rate per one MJ electricity generated. Most greenhouse gases are released during combusting fossil fuels, accounting for 78–95% of the total. The greenhouse gas emissions released from coal-fired power plants account for 81% of the total greenhouse gas emissions associated with electricity generation, and natural gas-fired power plants contribute about 16% of the total. The most significant regions for the total greenhouse gas emissions are the SERC (Southeastern Electric Reliability Council) and ECAR (East Central Area Reliability Coordination Agreement) regions, which account for 22% and 21% of the total, respectively. A sensitivity analysis on the generation and consumption based calculations indicates that the environmental profiles of electricity based on consumption are more uncertain than those based on generation unless exchange data from the same year are available because the exchange rates (region to region import and export of electricity) vary significantly from year to year.Conclusions and Outlook Those who are interested in the LCI data of the US electricity system can refer to the on-line version. When the inventory data presented in the on-line version are used in a life cycle assessment study, the distribution and transmission losses should be taken into account, which is about 9.5% of the net generation [1]. The comprehensive technical information presented in this study can be used in estimating the environmental burdens when new information on the regional fuel mix or the upstream processes is available. The exchange rates presented in this study also offer useful information in consequential LCI studies.     

A database for the life-cycle assessment of procter &; gamble laundry detergents

A Life-Cycle Inventory (LCI) and Assessment (LCA) database for laundry detergents of the Procter & Gamble Company (P&G) was constructed using SimaPro software. The input data needed to conduct a product LCI came from several different, supporting databases to cover supplier (extraction and manufacturing of raw materials), manufacturing of the detergent product, transportation, packaging, use and disposal stages. Manufacturing, packaging and transportation stages are usually representative of European conditions while the use and disposal stages are country specific and represent how consumers are using a specific product and how wastes are disposed of. The database has been constructed to allow Procter & Gamble managers to analyse detergent products from a system-wide, functional unit point of view in a consistent, transparent and reproducible manner. For demonstrative purpose, a life cycle inventory and a life cycle impact assessment of a P&G laundry detergent used in Belgium is presented. The analysis showed that more than 80% of the energy consumption occurs during the consumer use stage (mainly for heating of the water). Air and solid waste follow the same pattern, most of these being associated with die energy generation for the use stage. More than 98% of the biological oxygen demand, however, is associated with the disposal stage even after accounting for removal during treatment. Future challenges are the completion and/or updating of all detergent ingredient inventories.     

Utilization of household food waste for the production of ethanol at high dry material content

Background

Environmental issues and shortage of fossil fuels have turned the public interest to the utilization of renewable, environmentally friendly fuels, such as ethanol. In order to minimize the competition between fuels and food production, researchers are focusing their efforts to the utilization of wastes and by-products as raw materials for the production of ethanol. household food wastes are being produced in great quantities in European Union and their handling can be a challenge. Moreover, their disposal can cause severe environmental issues (for example emission of greenhouse gasses). On the other hand, they contain significant amounts of sugars (both soluble and insoluble) and they can be used as raw material for the production of ethanol.

Results

Household food wastes were utilized as raw material for the production of ethanol at high dry material consistencies. A distinct liquefaction/saccharification step has been included to the process, which rapidly reduced the viscosity of the high solid content substrate, resulting in better mixing of the fermenting microorganism. This step had a positive effect in both ethanol production and productivity, leading to a significant increase in both values, which was up to 40.81% and 4.46 fold, respectively. Remaining solids (residue) after fermentation at 45% w/v dry material (which contained also the unhydrolyzed fraction of cellulose), were subjected to a hydrothermal pretreatment in order to be utilized as raw material for a subsequent ethanol fermentation. This led to an increase of 13.16% in the ethanol production levels achieving a final ethanol yield of 107.58 g/kg dry material.

Conclusions

In conclusion, the ability of utilizing household food waste for the production of ethanol at elevated dry material content has been demonstrated. A separate liquefaction/saccharification process can increase both ethanol production and productivity. Finally, subsequent fermentation of the remaining solids could lead to an increase of the overall ethanol production yield.