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Abstract According to its ‘Energy Strategy 2050’ (case ‘new energy policy’) Switzerland aims to reduce its industrial electricity demand by 25% and 35% in 2035 and 2050 respectively compared to 2010. Electric motor driven systems in Swiss industry, which currently account for approximately 69% of the sector’s total electricity demand, are expected to contribute significantly to this strategy. This study assesses the potential of electricity savings for electric motor driven systems in industry and its associated specific costs and presents the results in the form of energy efficiency cost curves. For the short term, the economic potential for electricity savings in Swiss industrial electric motor systems is estimated at approximately 17%. The importance of accounting for additionality by using energy-relevant investment instead of total investment for the cost-benefit analysis in order to avoid underestimation of the economic electricity savings potential is demonstrated. The results of this analysis can serve as basis for formulating more effective policies and may also be applicable to other countries with similarly ambitious targets.

An augmented measurement uncertainty approach for CO2 emissions from coal-fired power plants with a focus on the often forgotten contributions from sampling errors occurring over the entire fuel-to-emission pathway is presented. Current methods for CO2 emission determination are evaluated in detail, from which a general matrix scheme is developed that includes all factors and stages needed for total CO2 determination, which is applied to the monitoring plan of a representative medium-sized coal-fired power plant. In particular sampling involved significant potential errors, as identified and assessed by the Theory of Sampling (TOS), which also shows how these can be eliminated and/or minimised. Since coal-related CO2 emission calculations not only require analytical results of the carbon content of coal itself but also of the by-products fly ash and bottom ash, sampling procedures of these three materials were also given full attention. A systematic error (bias) is present in the current sampling approach, which increases the present uncertainty estimate unnecessarily. For both primary sampling and analytical sample extraction steps, random variations, which hitherto only have been considered to a minor extent, have now also been fully quantified and included in the overall uncertainty. Elimination of all identified sampling errors lead to modified CO2 determination procedures, which indicate that the actual CO2 emission is approximately 20,000 t higher than the present estimate. Based on extensive empirical sampling experiments, a fully comprehensive uncertainty estimate procedure has been devised. Even though uncertainties increased (indeed one particular factor is substantially higher, the so-called “emission factor”), the revised CO2 emission budget for the case plant complies with the official pre-determined uncertainty levels maxima in the EU guidelines.

Abstract Reducing space heating demand from the residential building stock has been established as a crucial element of the energy transition across Europe. Focusing on Switzerland, this paper presents a bottom-up model (SwissRes) which allows to analyse the demand for space heating by building element and by building archetype (54 archetypes in total). The model is based on detailed data on the building envelope and heating systems of over 25,000 Cantonal Building Energy Performance Certificates (CECB PLUS). We identify three building characteristics which result in above-average final energy demand: rural typology (18% higher than urban), single-family houses (41% higher than multi-family) and in particular age of buildings (525% higher from newest to oldest). In combination, these three factors can lead to up to seven times higher demand per m2 and year in extreme cases compared to the most efficient archetype. Among buildings constructed before 1970, single-family houses (SFH) show very high specific final energy demand for space heating ranging between 170 and 200 kWh/m². On the national level, SFHs and multi-family houses (MFH) are featuring almost identical shares of total final energy demand. Buildings in suburban areas account for almost 50% of the total final energy demand. In total, the buildings constructed before 1980 account for 70% of the national final energy demand for space heating, with buildings constructed before 1920 contributing 22%. Most heat is lost through walls (40%) followed by windows (25%), roofs (17%) and the floor (18%). Losses from walls are particular high (73 kWh/m²) for buildings constructed between 1920 and 1945. Given the scalability of the model, it is readily applicable not only for the country as a whole but also for a province (canton), a city or a larger neighbourhood. The energy demand by archetype and building element identified with the SwissRes model can be used to assess the techno-economic potential of large-scale energy retrofit scenarios.

AbstractBiobased plastics have experienced fast growth in the past decade thanks to the public concerns over the environment, climate change and the depletion of fossil fuels. This perspective provides an overview of the current global market of biobased plastics, their material properties, technical substitution potential and future market (for 2020). In addition, the technology and market development of three biobased plastics, namely polylactide (PLA), biobased polyethylene (PE) and biobased epoxy resin, are discussed in detail. The emerging biobased plastics market is still small compared to traditional biobased polymers and biomaterials. The global capacity of the emerging biobased plastics was only 0.36 million tonnes in 2007. However, the market grew strongly between 2003 and 2007 (approx. 40% per year). The technical substitution potential of biobased plastics replacing petrochemical plastics is estimated at 90%, demonstrating the enormous potential of biobased plastics. Global capacity of biobased plastics is expected to reach 3.45 million metric tonnes in 2020. Starch plastics, PLA, biobased PE, polyhydroxyalkanoates (PHA) and biobased epoxy resin are expected to be the major types of biobased plastics in the future. Copyright © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd

Abstract The storage of heat in aquifers, also referred to as Aquifer Thermal Energy Storage (ATES), bears a high potential to bridge the seasonal gap between periods of highest thermal energy demand and supply. With storage temperatures higher than 50 °C, High-Temperature (HT) ATES is capable to facilitate the integration of (non-)renewable heat sources into complex energy systems. While the complexity of ATES technology is positively correlated to the required storage temperature, HT-ATES faces multidisciplinary challenges and risks impeding a rapid market uptake worldwide. Therefore, the aim of this study is to provide an overview and analysis of these risks of HT-ATES to facilitate global technology adoption. Risk are identified considering experiences of past HT-ATES projects and analyzed by ATES and geothermal energy experts. An online survey among 38 international experts revealed that technical risks are expected to be less critical than legal, social and organizational risks. This is confirmed by the lessons learned from past HT-ATES projects, where high heat recovery values were achieved, and technical feasibility was demonstrated. Although HT-ATES is less flexible than competing technologies such as pits or buffer tanks, the main problems encountered are attributed to a loss of the heat source and fluctuating or decreasing heating demands. Considering that a HT-ATES system has a lifetime of more than 30 years, it is crucial to develop energy concepts which take into account the conditions both for heat sources and heat sinks. Finally, a site-specific risk analysis for HT-ATES in the city of Hamburg revealed that some risks strongly depend on local boundary conditions. A project-specific risk management is therefore indispensable and should be addressed in future research and project developments.

A water-soluble organic redox couple (TT−/DTT) and new organic dyes (D45 and D51) have been developed for aqueous dye-sensitized solar cells (DSCs). An optimal efficiency of 3.5% was obtained using the D51 dye and an optimized electrolyte composition. The highest IPCE value obtained was 68% at 460 nm.

Climate change is threatening the well-being of both humans and nature, and new efficient strategies are needed to engage individuals in quickly adopting a more sustainable lifestyle. The present thesis addresses if Mental Accounting, as a central decision mechanism, can be used for designing behavioral interventions which are based on modifications of the choice architecture (“nudges”). Presenting evidence for such central mechanisms in the context of energy conservation, our findings reveal that individuals ascribe dissimilar environmental behaviors to different mental accounts, and are more likely to spend money labelled in a green context on pro-environmental purchases that is in accordance with the dedicated purpose of its account. We further indicate that mental accounts are dynamic and can be refined by a knowledge intervention which teaches the specific environmental impact of a series of energy-relevant behaviors. These mechanisms could be integrated into intervention strategies to increase energy conservation.