The current trend in biomass conversion technologies is toward more efficient utilization of biomass feedstock in multiproduct biorefineries. Many life-cycle assessment (LCA) studies of biorefinery systems have been performed but differ in how they use the LCA methodology. Based on a review of existing LCA standards and guidelines, this paper provides recommendations on how to handle key methodological issues when performing LCA studies of biorefinery systems. Six key issues were identified: (i) goal definition, (ii) functional unit, (iii) allocation of biorefinery outputs, (iv) allocation of biomass feedstock, (v) land use, and (vi) biogenic carbon and timing of emissions. Many of the standards and guidelines reviewed here provide only general methodological recommendations. Some make more specific methodological recommendations, but these often differ between standards. In this paper we present some clarifications (e.g. examples of research questions and suitable functional units) and methodological recommendations (e.g. on allocation).

The Swedish Armed Forces have large stocks of ammunition that were produced at a time when decommissioning was not considered. This ammunition will eventually become obsolete and must be destroyed, preferably with minimal impact on the environment and in a safe way for personnel. The aim of this paper is to make a comparison of the environmental impacts in a life cycle perspective of three different methods of decommissioning/destruction of ammunition, and to identify the environmental advantages and disadvantages of each of these destruction methods: open detonation; static kiln incineration with air pollution control combined with metal recycling, and a combination of incineration with air pollution control, open burning, recovery of some energetic material and metal recycling. Data used are for the specific processes and from established LCA databases. Recycling the materials in the ammunition and minimising the spread of airborne pollutants during incineration were found to be the most important factors affecting the life cycle environmental performance of the compared destruction methods. Open detonation with or without metal recycling proved to be the overall worst alternative from a life cycle perspective. The results for the static kiln and combination treatment indicate that the kind of ammunition and location of the destruction plant might determine the choice of method, since the environmental impacts from these methods are of little difference in the case of this specific grenade. Different methods for destruction of ammunition have previously been discussed from a risk and safety perspective. This is however to our knowledge the first study looking specifically on environmentally aspect in a life cycle perspective.

Rapportens övergripande syfte är att ge underlag för eventuella förslag till mål för ökad materialåtervinning i Sverige. Vi har gjort detta genom att beräkna potentialen (mängder) för ökad källsortering och materialåtervinning av avfall i Sverige, analysera miljömässiga och företagsekonomiska konsekvenser, samt samla information om den praktiska genomförbarheten.

Utifrån befintlig avfallsstatistik har vi identifierat vilka mängder av fraktionerna plast, papper och papp, metall, glas, gummi, gips, textil och WEEE som förekommer i blandade avfallskategorier men som skulle kunna källsorteras och materialåtervinnas.

Med ett scenario för hur avfallsmängderna kan antas öka till år 2030 har vi beräknat de potentiella miljöeffekterna i ett livscykelperspektiv av maximal källsortering och materialåtervinning jämfört med dagens nivåer. Klimatpåverkan, försurning, övergödning, bildning av fotooxidanter och total energianvändning utvärderades för plast, papper och papp, metall, glas och gummi. För samma scenario har de företagsekonomiska kostnaderna för ökad återvinning beräknats. Dessutom har olika aktörer intervjuats om vad de ser för hinder och möjligheter för ökad materialåtervinning.

Trots väl utbyggd källsortering och återvinning är fortfarande potentialen för ökad källsortering i Sverige betydande. Miljöbedömningarna visar att dagens system för avfallshantering medför nettovinster för miljön i ett livscykelperspektiv, genom att de resurser som återvinns från avfall indirekt ger minskad miljöpåverkan från andra sektorer. Denna positiva indirekta miljöpåverkan från avfallshanteringen kan öka ytterligare genom att öka återvinningen. Med hänsyn till möjliga miljövinster per kton material och tillgängliga mängder återvinningsbart material i blandat avfall, framstår ökad återvinning av plastavfall och pappers- och pappavfall som miljömässigt prioriterat. Ökad återvinning av metallavfall och gummiavfall skulle ge mindre men tydliga miljövinster. Ökad återvinning av glasavfall framstår inte som prioriterat. För textilavfall, gipsavfall och WEEE har inga beräkningar gjorts, men av olika skäl som redovisas i rapporten finns anledning att undersöka dessa fraktioner vidare.

Intervjuer och möten med representanter för olika avfallsbolag, återvinningsindustrier, byggsektorn och boendesektorn har gett en mångfald av synpunkter, idéer och förslag kring ökad källsortering och återvinning. Det rör allt ifrån internationell lagstiftning på avfallsområdet och övriga miljöområdet, till synpunkter på arkitekters ansvar att ta hänsyn till källsortering vid nyproduktion. Resultatet kan tolkas som att det finns praktiska förutsättningar att öka källsortering och återvinning i Sverige. Inga synpunkter om avgörande praktiska hinder framfördes. Överlag verkar det finnas en vilja att bidra till ökad källsortering och återvinning, förutsatt att det är motiverat ur miljösynpunkt, men det finns önskemål om tydligare målformuleringar och regelverk.

De företagsekonomiska kostnaderna för avfallshantering ökar med ökad återvinning, men i jämförelse med tillgängliga beräknade åtgärdskostnader för reduktion av växthusgaser inom transportsektorn, framstår kostnaderna som rimliga.

Life cycle assessments of circular economy measures (CE LCA) of consumer products have been criticized for oversimplifying important aspects of the use phase such as user behavior and rebound effects, limiting our understanding of the environmental performance of circular economy measures. This study tests the usefulness of a framework designed to facilitate accounting for such aspects, by applying the framework to a case study of reuse of shell jackets enabled by “premium secondhand” outdoor stores. Methods for collecting use phase data were user surveys and interviews with store managers. Using the framework on this case study generated several novel insights which are interesting in themselves and as inputs to CE LCA. For instance, secondhand shell jackets have a significantly lower frequency of use during their first use span compared to the second and to shell jackets in the linear reference scenario. This implies that reuse in this case does not function as a mere use extension of otherwise similar use phases as is commonly assumed. The generation of such insights, which hitherto have been lacking in CE LCAs, points to the usefulness of the framework as a tool for opening the “black box” of the use phase in CE LCAs to improve understanding of the environmental performance of circular economy measures.

Life cycle assessment (LCA) research on the performance of circular economy (CE) measures such as reuse, repair and remanufacturing has been criticized for inadequate consideration of functional equivalency of circular compared to new products, allocation between use phases, displacement rates, rebound effects, product use and user behavior. For such reasons, it has been argued that our understanding of the environmental performance of CE is poor and over-optimistic. Motivated by these criticisms, this paper presents an outline of a conceptual framework developed to improve CE LCA research. The framework was developed through literature review, workshops and ongoing CE LCAs in the sport and outdoor sector. The paper overviews challenges related to mentioned criticisms and possible approaches to addressing them, presents a model for how aspects influential to CE LCA results interrelate, and, proposes a structure for describing product-user life cycles more accurately. The outlined conceptual framework could be an important step towards improving CE LCAs and, ultimately, our understanding of environmental outcomes of CE. 

Waste management has developed in many countries and will continue to do so. Changes towards increased recovery of resources in order to meet climate targets and for society to transition to a circular economy are important driving forces. Scenarios are important tools for planning and assessing possible future developments and policies. This paper presents a comprehensive life cycle assessment (LCA) model for environmental assessments of scenarios and waste management policy instruments. It is unique by including almost all waste flows in a country and also allow for including waste prevention. The results show that the environmental impacts from future waste management scenarios in Sweden can differ a lot. Waste management will continue to contribute with environmental benefits, but less so in the more sustainable future scenarios, since the surrounding energy and transportation systems will be less polluting and also because less waste will be produced. Valuation results indicate that climate change, human toxicity and resource depletion are the most important environmental impact categories for the Swedish waste management system. Emissions of fossil CO2 from waste incineration will continue to be a major source of environmental impacts in these scenarios. The model is used for analyzing environmental impacts of several policy instruments including weight based collection fee, incineration tax, a resource tax and inclusion of waste in a green electricity certification system. The effect of the studied policy instruments in isolation are in most cases limited, suggesting that stronger policy instruments as well as combinations are necessary to reach policy goals as set out in for example the EU action plan on circular economy.

This article discusses the ORWARE tool, a model originally developed for environmental systems analysis of waste management systems, and shows its prospect as a tool for environmental technology chain assessment. Different concepts of technology assessment are presented to put ORWARE into context in the discussion that has been going for more than two decades since the establishment of the US Congressional Office of Technology Assessment (OTA). An even-handed assessment is important in different ways such as reproducibility, reliability, credibility, etc. Conventional technology assessment (TA) relied on the judgements and intuition of the assessors. A computer-based tool such as ORWARE provides a basis for transparency and a structured management of input and output data that cover ecological and economic parameters. This permits consistent and coherent technology assessments. Using quantitative analysis as in ORWARE makes comparison and addition of values across chain of technologies easier. We illustrate the application of the model in environmental technology chain assessment through a study of alternative technical systems linking waste management to vehicle fuel production and use. The principles of material and substance flow modelling, life cycle perspective, and graphical modelling featured in ORWARE offer a generic structure for environmentally focused TA of chains and networks of technical processes.

The environmental impact of Industry 4.0 and related technologies remains relatively unknown, with little research devoted to investigating the impact on sustainability aspects, resulting in a greater need for climate reporting. However, impacts of data transmission have historically been the least studied part of the information and communication technology sector, and there is currently no consensus on how to correctly assess it. In an attempt to guide process development within the area in the hopes that future life cycle assessments will be created, this study sought to identify, examine, and address potential challenges that might occur when assessing the environmental impact of network traffic during its life cycle. Through a combination of a literature review and semi-systematic research interviews with identified experts within the field of research, several areas in the form of knowledge gaps, unsolved methodological issues, and areas in need of further development were identified and assessed. The results show that eight key challenges exist in the areas of system boundaries, data collection methods, energy intensity metrics, transparency and data availability, age of data, allocation procedures, assumptions, and limited coverage of impact categories. Several approaches to address said challenges are presented, as well as areas in need of further investigation. It is furthermore suggested that the sector should strive to agree upon several parameters of significance to enable future harmonized life cycle studies of network traffic.

Waste management has gone through a history of shiftingproblems, demands, and strategies over the years. In contrastto the long prevailing view that the problem could be solved byhiding or moving it, waste is now viewed as a problem rangingfrom local to global concern, and as being an integral part ofseveral sectors in society. Decisive for this view has beensociety’s increasing complexity and thus the increasingcomplexity of waste, together with a general development ofenvironmental consciousness, moving from local focus on pointemission sources, to regional and global issues of more complexnature.

This thesis is about the development and application orware;a model for computer aided environmental systems analysis ofmunicipal waste management. Its origin is the hypothesis thatwidened perspectives are needed in waste managementdecision-making to avoid severe sub-optimisation ofenvironmental performance. With a strong foundation in lifecycle assessment (LCA), orware aims to cover the environmentalimpacts over the entire life cycle of waste management. It alsoperforms substance flow analysis (SFA) calculations at a ratherdetailed level of the system.

Applying orware has confirmed the importance of applyingsystems perspective and of taking into account site specificdifferences in analysis and planning of waste manage-ment,rather than relying on overly simplified solutions. Somefindings can be general-ised and used as guidelines to reduceenvironmental impact of waste management. Recovery of materialand energy resources from waste generally leads to netreductions in energy use and environmental impact, because ofthe savings this brings about in other sectors. Waste treatmentwith low rate of energy and materials recovery should thereforebe avoided. The exact choice of technology however depends onwhat products can be recovered andhow they are used.

Despite the complexity of the model and a certain degree ofuser unfriendliness, involved stakeholders have expressed thevalue of participating in orware case studies. It providesimproved decision-basis, but also wider understanding of thecomplexity of waste management and of environmental issues ingeneral.

The thesis also contains a first suggestion of a frameworkto handle uncertainty in orware, based on a review of types ofuncertainty in LCA and tools to handle it.

Life cycle assessment (LCA) is explored as an analytical tool in strategic environmental assessment (SEA), illustrated by case where a previously developed SEA process was applied to municipal energy planning in Sweden. The process integrated decision-making tools for scenario planning, public participation and environmental assessment. This article describes the use of LCA for environmental assessment in this context, with focus on methodology and practical experiences. While LCA provides a systematic framework for the environmental assessment and a wider systems perspective than what is required in SEA, LCA cannot address all aspects of environmental impact required, and therefore needs to be complemented by other tools. The integration of LCA with tools for public participation and scenario planning posed certain methodological challenges, but provided an innovative approach to designing the scope of the environmental assessment and defining and assessing alternatives.

Limitations of data quality and difficulties to assess uncertainty are long since acknowledged problems in LCA. During recent years a range of tools for improvement of reliability in LCA have been presented, but despite this there is still a lack of consensus about how these issues should be handled. To give basic understanding of data quality and uncertainty in LCA, key concepts of data quality and uncertainty in the context of LCA are explained. A comprehensive st~rvey of methods and approaches for data quality management, sensitivity analysis, and uncertainty analysis published in the LCA literature is presented. It should serve as a guide to further reading for LCA practitioners interested in improving data quality management and uncertainty assessment in LCA projects. The suitability of different tools for addressing different types of uncertainty and future needs in this field is discussed.

Computer models of municipal waste management have been developed initially to focus on cost minimization. As focus in local planning changed, the objective of these models now include environmental optimization. The development of life-cycle assessment (LCA) as a standard means to quantify environmental impact, and of substance flow analysis (SFA) as a means to track down causes of environmental problems has offered new possibilities in this field. The ORWARE (ORganic WAste REsearch) connects LCA and SFA for evaluation of environmental impact in waste planning. Despite the holistic approach of waste planning models, they do not necessarily facilitate decision making.

The environmental impact of the management of biodegradable waste in Stockholm, based mainly on incineration and landfilling, was compared to systems with significant nutrient recycling; large-scale composting, anaerobic digestion, and separate collection and utilization of urine. The systems' emissions, residual products, energy turnover, and resource consumption were evaluated from a life-cycle perspective, using a computerized model, ORWARE (ORganic WAste REsearch model).

Transportation was of relatively low importance to overall environmental impact, even at high rates of nutrient recycling. This is remarkable considering the geographical setting of Stockholm, with high population density and little nearby farmland. Ancillary systems, such as generation of electricity and district heating, were crucial for the overall outcome.

Increased recycling of nutrients in solid biodegradable waste in Stockholm can reduce net environmental impact, whereas separation of human urine to be spread as fertilizer cannot yet be introduced without increased acidification. Increased nutrient recycling from solid biodegradable waste inevitably increases spreading of metals on arable land. Urine is by far the least contaminated residual product. Spreading of all other residuals would be limited by their metal content.

Environmental consequences of implementing Uppsala's waste management plan have been analysed using ORWARE, a computerized static substance flow model based on life cycle assessment methodology. Normalizing emissions from waste management to total emission loadings in the municipality was tested as a means to improve the evaluation. It was found that anaerobic digestion of biodegradable waste can reduce net environmental impact, while large-scale composting either increases environmental impact or gives less reduction than anaerobic digestion. In either case, metal contamination of digester sludge or compost may limit the feasibility of the systems. Increased materials recycling has the potential of reducing environmental impact, provided that processing of recycled materials causes equal or less environmental impact than extraction and processing of virgin raw materials. Normalization showed that all impact categories were of roughly equal importance. It was shown that easy accessible data published by a Swedish municipality were sufficient to do a relatively comprehensive normalization.

At the core of EU and Swedish waste policy is the so-called waste hierarchy, according to which waste should first be prevented, but should otherwise be treated in the following order of prioritisation: reuse, recycling when environmentally motivated, energy recovery, and last landfilling. Some recent policy decisions in Sweden aim to influence waste management in the direction of the waste hierarchy. In 2001 a governmental commission assessed the economic and environmental impacts of introducing a weight-based tax on waste incineration, the purpose of which would be to encourage waste reduction and increase materials recycling and biological treatments This paper presents the results of a life cycle assessment (LCA) of the waste incineration tax proposal. It was done in the context of a larger research project concerning the development and testing of a framework for Strategic Environmental Assessment (SEA). The aim of this paper is to assess the life cycle environmental impacts of the waste incineration tax proposal, and to investigate whether there are any possibilities of more optimal design of such a tax. The proposed design of the waste incineration tax results in increased recycling, but only in small environmental improvements. A more elaborate tax design is suggested, in which the tax level would partly be related to the fossil carbon content of the waste.

Recycling of waste materials has been analysed from a life cycle perspective in a number of studies over the past 10-15 years. Publications comparing the global warming impact and total energy use of recycling versus incineration and landfilling were reviewed in order to find out to what extent they agree or contradict each other, and whether there are generally applicable conclusions to be drawn when certain key factors are considered. Four key factors with a significant influence on the ranking between recycling, incineration, and landfilling were identified. Producing materials from recycled resources is often, but not always, less energy intensive and causes less global warming impact than from virgin resources. For non-renewable materials the savings are of such a magnitude, that apparently the only really crucial factor is what material is replaced. For paper products, however, the savings of recycling are much smaller. The ranking between recycling and incineration of paper is sensitive to for instance paper quality, energy source avoided by incineration, and energy source at the mill.

Innovative technologies are required to offset increasing consumption and declining stocks of non-renewable resources. This study examines a possible enhancement of waste management and transportation by integrating two emerging technologies: municipal solid waste (MSW) gasification and fuel cell vehicles (FCVs), by fueling FCVs with hydrogen produced from gasified MSW. Material and energy flows were modeled in four MSW management scenarios (incineration, landfill, gasification, gasification with recycling) and four transportation scenarios (hybrid gasoline-electric, methanol FCVs, hydrogen FCVs using hydrogen from natural gas or municipal solid waste). Technological performance deemed feasible within 2010–2020 was assumed. Greenhouse gas emissions and non-renewable energy use were used to assess overall system performance. Gasification with hydrogen production performs as efficiently as incineration, but is advantageous compared to landfilling. Taking into account additional environmental criteria, the model suggests that hydrogen from MSW gasification for FCVs may provide benefits over conventional MSW treatment and transportation systems.

Life cycle assessment (LCA) has been used in waste management for the last two decades and hundreds of journal papers have been published. The use of LCA in waste management has provided a much-improved holistic view of waste management including waste flows and potential environmental impacts. Although much knowledge has been obtained from LCA studies, there is still a need to use LCA models in integrated waste management. This paper describes six areas where LCA is expected to play a role in waste management in the future: 1) understanding an existing waste management system; 2) improving existing waste management systems; 3) comparing alternative technologies/ technology performance; 4) technology development/prospective technologies; 5) policy development/strategic development; and 6) reporting. Illustrative examples are provided for each application area.

A simulation model, ORWARE (ORganic WAste REsearch), for the handling of organic waste in urban areas has been constructed. The model provides a comprehensive view of the environmental effects, plant nutrient utilisation and energy turnover for this large and complex system. The ORWARE model consists of several sub-models; sewage plant, incineration, landfill, compost, anaerobic digestion, truck transport, transport by sewers, residue transport and spreading of residues on arable land. The model is intended for simulating different scenarios, and the results are: emissions to air and water, energy turnover and the amount of residues returned to arable land. All results are presented, both as the gross figure for the entire system and figures for each process. Throughout the model all physical flows are described by the same variable vector, consisting of 43 substances. This extensive vector facilitates a thorough analysis of the results, but involves some difficulties in acquiring relevant data. In this paper, the model is described. Results from a hypothetical case study are presented in a companion paper.

The environmental impacts of nitrogen emissions from soil resulting from the use of organic fertilizers, such as manure, are large compared with the corresponding impacts of mineral fertilizers. However, soil emissions are rarely included in systems analysis of waste management strategies. This study examines whether the inclusion of soil emissions can affect the environmental ranking of systems for managing solid biodegradable waste. Waste management scenarios based on incineration, anaerobic digestion and composting, respectively, were compared. The scenarios were analysed using the organic waste research (ORWARE) simulation model. A simplified model for calculating nitrogen availability and emissions was also constructed. Life-cycle analysis methodology was used for choosing system boundaries and evaluating the results. Global warming, acidification and eutrophication were the impact categories considered. The results indicate the vital importance of considering nitrogen emissions from soil when comparing biological waste management systems with other waste management methods, especially with regard to eutrophication effects. Soil emissions are also important when comparing the environmental impacts of anaerobic digestion and composting systems. However, the variation in nitrogen emissions from soil is large and depends on the spreading technique used, climate, drainage and soil texture

In assessments of the environmental impacts of waste management, life-cycle assessment (LCA) helps expanding the perspective beyond the waste management system. This is important, since the indirect environmental impacts caused by surrounding systems, such as energy and material production, often override the direct impacts of the waste management system itself. However, the applicability of LCA for waste management planning and policy-making is restricted by certain limitations, some of which are characteristics inherent to LCA methodology as such, and some of which are relevant specifically in the context of waste management. Several of them are relevant also for other types of systems analysis. We have identified and discussed such characteristics with regard to how they may restrict the applicability of LCA in the context of waste management. Efforts to improve LCA with regard to these aspects are also described. We also identify what other tools are available for investigating issues that cannot be adequately dealt with by traditional LCA models, and discuss whether LCA methodology should be expanded rather than complemented by other tools to increase its scope and applicability.

The importance of sustainable development (SD) is hardly possible to refute; however, sustainable development has been a relatively peripheral subject in computer-related engineering educations. Sustainability, with its global and potentially all-encompassing connotations, is still seen by many Information and Communication Technology (ICT) students as a topic of little relevance to their future careers. So how can teachers convince these students that sustainability is a topic that can be both relevant and interesting for them? From the point of view of the student; “What’s in it for me?”.

In this paper we describe and compare our efforts to plan and teach three introductory courses on SD in three different ICT-related educational programmes at KTH Royal Institute of Technology. The courses were planned separately, but they will be analysed together. We discuss two dimensions that we have found to be imperative in our endeavour to engage our students. The first dimension is to handle the balance between sustainability on a general level versus sustainability as specifically related to ICT. The second dimension is to handle the tension between teaching facts versus an emphasis on students’ reflections and/or practicing skills. We argue that overcoming the challenge of making sustainability relevant to the students is central for successfully teaching these courses. 

Different waste treatment options for municipal solid waste have been studied in a systems analysis. Different combinations of incineration, materials recycling of separated plastic and cardboard containers, and biological treatment (anaerobic digestion and composting) of biodegradable waste, were studied and compared to landfilling. The evaluation covered use of energy resources, environmental impact and financial and environmental costs. In the study, a calculation model ( ) based on methodology from life cycle assessment (LCA) was used. Case studies were performed in three Swedish municipalities: Uppsala, Stockholm, and Älvdalen.

The study shows that reduced landfilling in favour of increased recycling of energy and materials lead to lower environmental impact, lower consumption of energy resources, and lower economic costs. Landfilling of energy-rich waste should be avoided as far as possible, partly because of the negative environmental impacts from landfilling, but mainly because of the low recovery of resources when landfilling.

Differences between materials recycling, nutrient recycling and incineration are small but in general recycling of plastic is somewhat better than incineration and biological treatment somewhat worse.

When planning waste management, it is important to know that the choice of waste treatment method affects processes outside the waste management system, such as generation of district heating, electricity, vehicle fuel, plastic, cardboard, and fertiliser.

The aim of this consequential life cycle assessment (LCA) is to compare district heating based on waste incineration with combustion of biomass or natural gas. The study comprises two options for energy recovery (combined heat and power (CHP) or heat only), two alternatives for external, marginal electricity generation (fossil lean or intense), and two alternatives for the alternative waste management (landfill disposal or material recovery). A secondary objective was to test a combination of dynamic energy system modelling and LCA by combining the concept of complex marginal electricity production in a static, environmental systems analysis. Furthermore, we wanted to increase the methodological knowledge about how waste can be environmentally compared to other fuels in district-heat production. The results indicate that combustion of biofuel in a CHP is environmentally favourable and robust with respect to the avoided type of electricity and waste management. Waste incineration is often (but not always) the preferable choice when incineration substitutes landfill disposal of waste. It is however, never the best choice (and often the worst) when incineration substitutes recycling. A natural gas fired CHP is an alternative of interest if marginal electricity has a high fossil content. However, if the marginal electricity is mainly based on non-fossil sources, natural gas is in general worse than biofuels.

A simulation model, ORWARE (ORganic WAste REsearch) is described. The model is mainly used as a tool for researchers in environmental systems analysis of waste management. It is a computer-based model for calculation of substance flows, environmental impacts, and costs of waste management. The model covers, despite the name, both organic and inorganic fractions in municipal waste. The model consists of a number of separate submodels, which describes a process in a real waste management system. The submodels may be combined to design a complete waste management system. Based on principles from life cycle assessment the model also comprises compensatory processes for conventional production of e.g. electricity, district heating and fertiliser. The compensatory system is included in order to fulfil the functional units, i.e. benefits from the waste management that are kept constant in the evaluation of different scenarios. ORWARE generates data on emissions, which are aggregated into different environmental impact categories, e.g. the greenhouse effect, acidification and eutrophication. Throughout the model all physical flows are described by the same variable vector, consisting of up to 50 substances. The extensive vector facilitates a thorough analysis of the results, but involves some difficulties in acquiring relevant data. Scientists have used ORWARE for 8 years in different case studies for model testing and practical application in the society. The aims have e.g. been to evaluate waste management plans and to optimise energy recovery from waste.