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Economic and environmental impact assessments are increasingly being adopted in the design and implementation of emerging systems. However, their emerging nature leads to several assessment challenges that need to be addressed to ensure the validity and usefulness of results in understanding their potential performance and supporting their development. There is the need to (i) account for spatial and temporal variability to allow a broader perspective at an early stage of development; (ii) handle uncertainties to systematically identify the critical factors and their interrelations that drive the results; (iii) integrate environmental and economic results to support sound decision-making based on two sustainability aspects. To address these assessment challenges, this study presents an alternative approach with the following corresponding features: (i) multiple scenario development to conduct an exploratory assessment of the systems under varying conditions and settings, (ii) global sensitivity analysis to identify the main critical factors and their interrelations, and (iii) trade-off and ecoefficiency analysis to integrate the economic and environmental results. The integrated approach is applied to a case study on plasma gasification for solid waste management. The results of the study highlight how the approach allows the identification of the dynamic relations between project settings and surrounding conditions. For example, the choice of gasifying agent largely depends on the background energy system, which dictates the impacts of the process energy requirement and the savings from the substituted energy of the syngas output. Based on these findings, the usefulness and validity of the proposed integrated approach are discussed in terms of how the key assessment challenges are addressed and how it can provide guidance for the development of emerging systems.

Various recent policy initiatives indicate an increasing need for a comprehensive overview of potentially extractable anthropogenic resources, in order to compare them with geogenic resources. Therefore, a method has been developed to evaluate and classify anthropogenic resource deposits and to prioritize potential extraction projects in a transparent manner. In this study we present how anthropogenic resources can be systematically integrated into the United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009 (UNFC-2009). The main goal is to illustrate different settings of anthropogenic resource classification, and to provide specific criteria to map different types of anthropogenic resources within the three dimensions of UNFC-2009, i.e. “knowledge on composition and extractable material content”, “technical and project feasibility” and “socioeconomic viability”. Projects for recovering materials from an old landfill, from obsolete PCs (personal computers), and from in-use wind turbines are exemplarily evaluated and classified under UNFC-2009. The economic results depend on the respective scenarios, where the timing of mining is varied, different organizational and societal settings are compared and different choices for technological options are made. While landfill mining under current conditions is not economically viable, the final result might look different in the future with changing key modifying factors, such as increasing secondary raw material prices. Mining materials from obsolete PCs and from permanent magnets in in-use wind turbines would both yield positive economic results for all investigated scenarios.

In light of various policy initiatives promoting the efficient use of resources, this study investigates how anthropogenic resources could be classified under the United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009 (UNFC-2009). Compared to geogenic resources, anthropogenic deposits are more heterogeneous and subject to various dynamics, due to the human impact on their genesis. Often they must be assessed not only under aspects of resource recovery, but with respect to alternative waste treatment and disposal options. Factors, which are influencing the classification of anthropogenic resources, vary during the individual phases of resource classification, namely prospection, exploration and evaluation. During the (pre)prospection phase, the preconditions defining the setting for the following resource classification are checked, i.e. the deposit's status of availability for mining (“in-use stocks”, “obsolete stocks” or “waste flows”) as well as the specific handling and mining condition. System variables, which determine the potentially extractable amount of materials, play a major role during the exploration phase, e.g. technological choices for recovery. In the evaluation phase, modifying factors with direct impact on the project's economics are investigated, such as prices for secondary products, (avoided) costs and possibly monetized externalities. Challenges and potentials of classifying different types of anthropogenic resources under UNFC-2009 are illustrated for two different cases: Mining an old landfill (obsolete stock) is contrasted in a qualitative discussion to mining E-waste (waste flow). Finally, an operative evaluation procedure is outlined, which is still to be refined and illustrated via case studies.