What environmental constraints will materials have to face in the future? Can current measurement tools like LCA (Life Cycle Analysis) support the choices of material and adapt to these constraints to pave the way to a sustainable world? Are there some alternative or complementary approaches to enhance the quality of information for decision makers? The aim of this article is to provide answers to these three questions. The society of tomorrow, in the second half of the 21st century, will be a society where the circular economy will play a more important role and thus will help reduce materials waste. This is a critical aspect of sustainability. To get there, the decisions have to be enlightened and fair, because the decisions (or non-decisions) made today shape the world that future generations will have to manage. Furthermore, Lord Kelvin used to say: “what you can’t measure, you can’t improve”. Therefore, these decisions have to be supported by measurement tools that will properly capture the stakes of reuse and recycling at the end of life of products. Today, LCA is the common tool used to address this matter. However, the present article has shown that LCA cannot incorporate the whole complexity of sustainability. LCA is good at considering micro-scale issues, comparing one solution with another, in a static approach. How can it give right directions to decision makers in order to support the vision of a circular economy? The application of different standards showed that it is not easy at all and that recycling product at their end of life are not rewarded equally and sometimes not promoted at all. Therefore rebound effects leading to contradictory decisions may occur. LCA alone is not enough to make enlightened decisions. It should be complemented by other methods. This was proposed in the last part. Based on the IPAT equation, this approach tries to capture different aspects that are not addressed properly by LCA, due to the fact that the functional unit is too restrictive, that the time dimension and prospective approach should be more integrated, and that it should enlarge the scale of the analysis to the macro-economy and the socio-economy. It should also recognize that the efforts have to be shared by different players including material industry and manufacturers, policy makers and society in general. As a general conclusion, we are convinced that tomorrow’s society will recognize the value of materials that are recyclable and reusable, like steel has been for many decades. But there is still a clear need to addressing, in research and development, the improvement of the metrics, combining social, environmental and economic assessment, so that the sustainability value of materials is properly measured. These are the objectives of the Sovamat Initiative and the SAM conferences.

The European Waste Framework Directive (2008/98/EC) explicitly specifies the hierarchy for waste management: prevention, preparation for re-use, recycling, other recovery actions, disposal. When selecting waste management options, this waste hierarchy should be followed. A deviation can only be justified by Life Cycle Thinking (LCT) on the overall impacts. The application of this principle in the Flemish waste management practice triggered the need for evaluation of treatment options for several waste streams. Alternative treatments were evaluated for waste batteries, used frying oils and waste oil. The evaluation methodology combined life cycle assessment with technical and economical viability criteria. These cases show that LCT does not allow to establish a “general priority order”. In each case reasons for deviation from the standard waste hierarchy could be given, but also none of the evaluated options can be considered as the best. The evaluation showed that the priority is largely dependent on location-specific characteristics of inputs, outputs, processes and installations and that the establishment of local and global environmental priorities always implies a value choice. In this presentation, we will present the results of the three cases and provide a methodological framework for life cycle thinking in waste management policy.

There is an increasing need for expanding the scope of traditional life cycle studies to answer system-wide sustainability questions. This has resulted in a framework for life cycle sustainability analysis (LCSA). Since the framework was first published in 2009, as one of the outcomes of the CALCAS project, several views and considerations concerning the methodological approach have been published. However, until now practical experience with LCSA is very limited. This paper reports first efforts and experiences in bringing the LCSA framework into practice by assessing the sustainability of solar fuels. Starting point of the project is the hypotheses that new technologies can only be practically implemented if they fit into a socially, economically and ecologically sustainable context. The analysis therefore aims at identifying performance criteria which a new technology needs to fulfil in order to compete in the existing market. It is argued that a LCSA study should be initiated with a broad but relevant system description as the first of in total five steps Of this five step approach, the first – system description – is discussed here. The system description identifies and describes the technological description, the intended application of a technology, which share of specific demand for service will be met, which other technologies contribute in meeting this demand, the (relevant indicators for addressing )sustainable impacts of meeting the demand and developments over time. By doing so it provides a solid basis for further steps in the LCSA study.

Especially in OECD countries, the reduction of primary energy consumption is a major task to avoid further increase in CO2 emissions. Since 37% of the annual energy consumption is related to the building sector, it is a major challenge for the future to develop methods for significant improvement of the energy efficiency of building design, construction and operation. It has to be noted that the development of sustainable buildings addresses both engineering and social aspects. From an engineering viewpoint methods to improve the ecologic efficiency of buildings by increasing the lifetime have to be provided. From a social viewpoint these new approaches must take the future needs of society into consideration. In addition, also governance structures and the regulatory framework for the construction and operation of buildings need to be modified in the direction of sustainability. The article will initially identify the major research topics for the development of sustainable design principles for buildings. Afterwards, structural requirements will be defined and translated into required property profiles for building materials. Herein, both mechanical and functional properties are of importance, so that approaches will be presented how to combine these properties in composite building materials. With respect to mechanical properties, new steels will have to be developed with an improved balance of strength and ductility, so that some promising steel design concepts will be shown. Additionally, new approaches for the failure assessment of these new steel types will be presented to enhance the exploitation of the characteristics of the innovative materials.

Concerns for climate change and declining oil reserves lead to a shift of transportation systems in many industrial countries. However, alternative drive concepts contain to some extent critical raw materials. Since the availability of certain raw materials could be decisive for the success of emerging technologies, concerns are growing about the potential limitation of resources. This brought about a growing attention to the subjects of criticality and resource security of raw materials by science, policy and industry. Four of the resulting surveys are described in terms of their framing of criticality, their indicators for evaluating criticality, and their rankings of potentially critical raw materials. Critical raw materials are used in alternative drive concepts because of their specific properties. The focus of our work lies on batteries for electric vehicles with special attention to lithium-ion batteries being one of the most promising candidates for energy storage there. Lithium-ion batteries use as major cathode materials lithium, manganese and cobalt, all of which are potential critical. A material flow model of the global manganese cycle is developed. It could be identified that there is a lack of relevant data for processes and flows. The lack of data impedes a comprehensive view and therefore no final conclusions could be drawn, which advice the need for further research. Using manganese as an example, it could be illustrated how material flow analysis can contribute to compiling relevant preparatory work that can subsequently serve as a basis for a prospective support of a criticality evaluation and to inform stakeholders and policy makers about the effectiveness of various interventions to reduce the risk or the effects of supply chain disruptions.

The challenges of sustainable urban development are tremendous. More than half of the earth’s population lives in cities and there is an upward trend. On a global scale, the cities are the greatest greenhouse gas producers and the biggest consumers of water and energy. Urbanisation, climate change and demographic change are forcing metropolises to make their infrastructure more efficient, be environmentally friendlier, keep the high standard of living and if possible save costs. One of the keys is the selection of materials. Buildings are responsible for 40% of the energy consumption and approx. 21% of produced CO2 worldwide. Scientists and researchers from all over the world are looking into new technologies, so that energy could be used efficiently and CO2 emissions reduced, without having to pass on comfort or “lifestyle habits” [http://www.siemens.de/nachhaltige-stadtentwicklung/nachhaltige-stadtentwicklung.html?stc=deccc020187 (accessed 27.04.2012)]. Sustainability is a complex term, used in the last 2–3 decades. It involves more than just the environment and it concerns every one of mankind [cf. Schlussbericht der Enquete-Kommission Globalisierung der Weltwirtschaft – Herausfordeung-en und Antworten, Drucksache 14/9200, http://dipbt.bundestag.de/dip21/btd/14/092/1409200.pdf, p. 393]. This is why social and engineering scientists from RWTH Aachen University have joined in their efforts to figure out how used shipping containers, which are in abundant supply, can play their role in the future of sustainable construction. After they have been used several times, freight containers are considered disused and begin to accumulate in the surroundings of seaports and harbours. The energy to produce a container is significant and considered wasted if the steel box has completed only a few runs. The first association with containers can be a cold and uncomfortable cell, however, after a glance at the properly adapted shipping containers, converted into cosy, pretty and affordable habitable spaces, this preconception can soon be dismissed. Research has shown, in terms of environment and design, they are innovative and intelligent – building with cargo containers is cheaper, “greener”, faster and more flexible than traditional methods. With the increase of life expectancy and population continuing to grow, demand for housing will rise as well. Demographic change and the demand will contribute to rising construction prices. Habitation is one of the essential basic needs of all people. If one takes into account population growth and the timely provision of housing for all people, existing construction methods have to be adapted and new ones developed. Space in the social sense is an expression of the society and not its reflexion [cf. M. Castells, The Rise of Network Society, Wiley-Blackwell, 2010, p. 440f]. Bearing in mind the diversity in Europe’s population and the anxiety for environmental protection and sustainability, also the contrariness in environmental awareness and behavior, likewise eco-friendly and polluting habits in our everyday life, which are linked together in a various and unconsidered way, validates having different levels of environmental awareness depending on the different segments of society. We speak here of the “patchwork” – character of lifestyles and values, which is illustrated and explained easily with the Sinus-Milieu-Model [Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit, Umweltbewusstsein in Deutschland 2010, Ergebnisse einer repräsentativen Bevölkerungsumfrage, 2010, p. 13]. This paper discusses the existing Sinus-Milieus® [http://www.sinus-institut.de/en/ (accessed 27.04.2012)] and their features and show hereupon the growing demand in the society on flexible living concepts and habitat designs. The theory supports, that building with steel containers could be a real solution for the social and environmental problems. A continuously availability of shippingcontainers as a building block is expected and therefore the construction business with steel containers has a great potential in terms of sustainability towards a sustainable construction in a sustainable city.

The increasing proportion of renewable resources in electricity mixes, the decentralization of energy supply and the growing use of electric vehicles demands the challenging development of reliable, cost effective and flexible energy storage technologies. One option are electrochemical energy storage systems with high specific power and high specific energy density. One of the most promising electrochemical energy storage systems is the lithium-ion batteries (LIB) which are customized regarding size, weight, specific energy and specific capacity what makes batteries ready for operation under different conditions such as emerging electric power systems, grid support or electric mobility [1]. Even though the lithium-Ion technology for traction batteries is not yet widely applied, experiments and first use experiences show that it is a promising electric energy storage system for electric mobility. However, the environmental impacts of battery production, use and recycling are not well understood. To gain a better understanding about the ecological properties of LIBs material and energy flow analysis (MEFA) is conducted. The MEFA defines the possible sources and consumers of relevant materials, substances, pollutants and energy flows [2, 3]. The presented study analyses the consumed materials and energy as well as the emitted substances and waste heat of different LIBs. The main focus of the MEFA is on the production phase and includes active and passive components and material such as metal-salts, electrode materials, other functional metals (e.g. current collectors, casing, etc.), plastics (e.g. separator) and electrolytes [4--7] and on energy consumption as well.

The year of 2012 marks the 20th anniversary since the concept of ecological footprint was introduced to the global community for the first time. Nowadays footprint studies have gained extensive debates as well as popularity. In this paper, we define the footprint family as an indicator system of selected footprints that measure some aspects of human impacts on the environment. A relatively comprehensive introduction and comparison of four key footprints is represented by listing their characteristics in different aspects. The interaction among these footprints within the footprint family is classified into three types: overlap, contradiction and complement. The description of each type is provided in detail. Limitations and uncertainties of the footprint family, and priorities for further improvement are also performed. This research makes a preliminary attempt at developing the conceptual framework for the footprint family, which allows us to examine the performance of footprints combination. The footprint family will serve as a tool for integrating footprints on human impacts assessment, and a support for environmental decision-making.

Emergy evaluation (EME) is an environmental assessment method which is gaining international recognition and has increasingly been applied during the last decade. Emergy represents the memory of the geobiosphere exergy (environmental work) – measured in solar emjoules (seJ) – that has been used in the past or accumulated over time to make a natural resource available. The rationale behind the concept of Emergy is the consideration that all different forms of energy can be sorted under a hierarchy and measured with the common metric of the seJ, which is then the yardstick through which all energy inputs and outputs can be compared with each other. For this reason EME is suggested to be a suitable method of environmental accounting for a wide set of natural resources, and can be used to define guidelines for sustainable consumption of resources. Despite those interesting features, EME is still affected by several drawbacks in its calculation procedures and in its general methodological background, which prevent it from being accepted by a wider community. The main operational hurdle lays in the set of mathematical rules (known as Emergy algebra rules) governing EME, which do not follow logic of conservation and make their automatic implementation very difficult. This work presents an open source code specifically created for allowing a rigorous Emergy calculation (complying with all the Emergy algebra rules). We modeled the Emergy values circulating in multi-component systems with an oriented graph, formalized the problem in a matrix-based structure and developed a variant of the well-known track summing algorithm to obtain the total Emergy flow associated with the investigated product. The calculation routine (written in C++) implements the Depth First Search (DFS) strategy for graph searches. The most important features of the calculation routine are: (1) its ability to read the input in matrix form without the need of drawing a graph; (2) its rigorous implementation of the Emergy rules; (3) its low running time, which makes the algorithm applicable to any system described at the level of detail nowadays made possible by the use of the available life cycle inventory (LCI) databases. A version of the Emergy calculation routine based on the DFS algorithm has been completed and is being tested on case studies involving matrices of thousands of rows and columns, describing real product production systems.

Materials have been invented by mankind in the course of prehistory and history and have evolved during this long period of time to fit the parallel changes in technological epistemes. Materials, therefore, have been a cumulative technological commodity, because of the continuity that this mechanism of change has ensured Structural materials, of which all anthropogenic artefacts are made and with which they are made (machines, process tools, etc.), have been more especially enduring and have carved themselves specific roles in our world that survive across major paradigm shifts and Kondratief cycles. Materials are analyzed here in terms of their physico-chemical nature (or physio-chemical in the case of natural, renewable materials) and of their footprints on energy consumption and greenhouse gas emissions, two of the major lenses through which the sustainability of our economic world is presently observed. The picture that comes out of this examination is that of complementarity and cooperation between materials, with competition acting as a sting to avoid a slack in technology but no pushing any of them out of their market, at least globally. This cohabitation, akin to a natural selection mechanism in a global ecosystem, may be the real driver of dematerialization, a trend which population growth and urbanization forces on mankind.