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Clearly and accurately communicating the economic, environmental, and social benefitsof solar PV prosumerism poses significant challenges. Previous research shows that governmentpolicies and public engagement campaigns can positively impact solar prosumerism; however, littleis known about the quality and accuracy of information exchanged between rooftop solar installersand potential prosumers. This study addresses part of this gap with a mixed methods approach. First,a multimodal discourse analysis of installation proposals from seven home solar installers in Madridshows accurate and reasonable financial benefits alongside incongruent social and environmental benefits. Second, the calculated efficiency of the seven proposed solar installations is compared with the efficiency of four different PVSC solar arrays using actual load and generation profiles. The results show that (i) the high variability of actual household demand on the minute-by- minutelevel significantly decreases self-consumption rate and profitability in comparison with the rates estimated using hourly or monthly, and (ii) the grouping of households into solar communities should significantly increase self-consumption and profitability. Therefore, using minute by minute time series in home solar estimations would reveal an added value and social benefit that is commonly overlooked. We conclude with recommendations for future research and multimodal communication campaigns that balance the benefits of individual prosumerism and community solar.

The ongoing energy transition is causing rapid changes in the electricity system and, in consequence, the environmental impacts associated with electricity generation. In parallel, the daily variability of generation increases with higher shares of renewable energies. This affects the potential environmental impacts or benefits of devices with variable load or power, such as electric vehicles, storage systems or photovoltaic home systems. However, recent environmental assessments of the actual benefit of such systems are scarce, with existing assessments majorly using average grid mixes that are frequently outdated and disregard the dynamic nature of renewable generation. This article provides detailed hourly average and marginal electricity mixes for each month of the year, determined for Spain as an illustrative country with a diversified (renewable) power generation portfolio that experienced a rapid change in the last years. These are combined with specific life-cycle emission factors for each generation technology. Main drivers for the impacts of the marginal mix turn out to be natural gas plants and imports, but also pumped hydropower due to its comparably low storage efficiency. Applied to a hypothetical photovoltaic rooftop installation, the differences between environmental assessments on hourly and on annual basis are found to be surprisingly low when assuming that the generated electricity replaces the average grid mix, but substantial when considering the marginal generation mix (i.e., the generation technologies that respond to a change in demand at a given time). This highlights the importance of considering the dynamics of the electricity system and the corresponding marginal electricity mixes when optimizing flexible load or generation technologies under environmental aspects.

Sodium-ion batteries are increasingly being promoted as a promising alternative to current lithium-ion batteries. The substitution of lithium by sodium offers potential advantages under environmental aspects due to its higher abundance and availability. However, sodium-ion (Na-ion) batteries cannot rely on graphite for the anodes, requiring amorphous carbon materials (hard carbons). Since no established market exists for hard carbon anode materials, these are synthesised individually for each Na-ion battery from selected precursors. The hard carbon anode has been identified as a relevant driver for environmental impacts of sodium-ion batteries in a recent work, where a significant improvement potential was found by minimising the impacts of the hard carbon synthesis process. In consequence, this work provides a detailed process model of hard carbon synthesis processes as basis for their environmental assessment. Starting from a review of recent studies about hard carbon synthesis processes from different precursors, three promising materials are evaluated in detail. For those, the given laboratory synthesis processes are scaled up to a hypothetical industrial level, obtaining detailed energy and material balances. The subsequent environmental assessment then quantifies the potential environmental impacts of the different hard carbon materials and their potential for further improving the environmental performance of future Na-ion batteries by properly selecting the hard carbon material. Especially organic waste materials (apple pomace) show a high potential as precursor for hard carbon materials, potentially reducing environmental impacts of Na-ion cells between 10 and 40% compared to carbohydrate (sugar) based hard carbons (the hard carbon material used by the current reference work). Waste tyres are also found to be a promising hard carbon precursor, but require a more complex pre-treatment prior to carbonisation, why they do not reach the same performance as the pomace based one. Finally, hard carbons obtained from synthetic resins, another promising precursor, score significantly worse. They obtain results in the same order of magnitude as the sugar based hard carbon, mainly due to the high emissions and energy intensity of the resin production processes., Citation: Matériaux & Techniques Volume 107, Number 5, 2019 Materials and Society: The Circular Economy (SAM13) Article Number 503 Number of page(s) 18 DOI https://doi.org/10.1051/mattech/2019029 Published online 09 January 2020 https://www.mattech-journal.org/articles/mattech/abs/2019/05/mt190046/mt190046.html Published / Copyright by EDP Sciences

The share of power from fluctuating renewable energies such as wind and solar is increasing due to the ongoing climate change. It is therefore essential to use technologies that can compensate for these fluctuations. Experiments at 1 MWth scale were carried out to evaluate the operational flexibility of a circulating fluidized bed (CFB) combustor during transient operation from 60% to 100% load. A typical load following sequence for fluctuating electricity generation/demand was reproduced experimentally by performing 4 load changes. The hydrodynamic condition after a load change depends on if the load change was in positive or negative direction due to the heat stored in the refractory/bed material at high loads and released when the load decreases. A 1.5D-process simulation model was created in the software APROS (Advanced Process Simulation) with the target of showing the specific characteristics of a CFB furnace during load following operation. The model was tuned with experimental data of a steady-state test point and validated with the load cycling tests. The simulation results show the key characteristics of CFB combustion with reasonable accuracy. Detailed experimental data is presented and a core-annulus approach for the modeling of the CFB furnace is used.

Sodium-ion batteries (SIB) are among the most promising type of post-lithium batteries, being promoted for environmental friendliness and the avoidance of scarce or critical raw materials. However, the knowledge-base in this regard is weak, and comparatively little is known about the environmental performance of different SIB types in comparison with current lithium-ion batteries (LIB) under consideration of the whole battery life cycle (‘cradle-to-grave’). This work provides a complete and comprehensive update of the state of knowledge in the field of life cycle assessment of SIB. It develops and discloses a specific tool for dimensioning and assessing SIB cells, including a cell-specific model of an advanced hydrometallurgical recycling process. It provides the corresponding inventory data for five different types of SIB and compares their environmental impacts with those of competing LIB, taking into account the full life cycle (cradle-to-grave) and an individual cell dimensioning based on electrochemical considerations. Recycling is found to be highly relevant for minimizing environmental impacts of the batteries, though its benefit depends strongly on the individual cell chemistry. Deep recycling might not be favourable for cathodes based on abundant materials and could even increase impacts. Especially the assessed manganese and nickel–manganese based SIB chemistries show promising results, given that they achieve at least similar lifetimes as their LIB counterparts.

Co-combustion of biomass and solid fuels from wastes in existing highly efficient power plants is a low-cost solution that can be applied quickly and with low effort to mitigate climate change. Circulating fluidized bed combustion has several advantages when it comes to co-combustion, such as high fuel flexibility. The operational flexibility of circulating fluidized bed (CFB) co-combustion is investigated in a 1 MWth pilot plant. Straw pellets and refuse-derived fuel (RDF) are co-combusted with lignite at full load and part loads. This study focusses on the impact on the hydrodynamic conditions in the fluidized bed, on the heat transfer to the water/steam side of the boiler, and on the flue gas composition. The study demonstrates the flexibility of CFB combustion for three low-rank fuels that differ greatly in their properties. The co-combustion of RDF and straw does not have a negative effect on hydrodynamic stability. How the hydrodynamic conditions determine the temperature and pressure development along the furnace height is shown. The heat transfer in the furnace linearly depends on the thermal load. It increases slightly with an increasing share of straw and the influence of the hydrodynamic conditions on the heat transfer was low.

Sodium-ion batteries are emerging as potential alternatives to lithium-ion batteries. This study presents a prospective life cycle assessment for the production of a sodium-ion battery with a layered transition metal oxide as a positive electrode material and hard carbon as a negative electrode material on the battery component level. The complete and transparent inventory data are disclosed, which can easily be used as a basis for future environmental assessments. Na-ion batteries are found to be promising under environmental aspects, showing, per kWh of storage capacity, environmental impacts at the lower end of the range published for current Li-ion batteries. Still significant improvement potential is given, especially by reducing the environmental impacts associated with the hard carbon production for the anode and by reducing the nickel content in the cathode active material. For the hard carbons, the use of organic waste can be considered to be promising in this regard. Nevertheless, when looking at the energy storage capacity over lifetime, achieving a high cycle life and good charge–discharge efficiency is fundamental. This represents the main challenge especially when competing with LFP–LTO type Li-Ion batteries, which already show extraordinarily long lifetimes.

Einleitung: Zur operativen Versorgung von Unterkiefer-Collumfrakturen existiert eine Vielzahl von extra- und intraoralen Zugangsmöglichkeiten. Trotz einer verbesserten Übersicht und Erleichterung der Frakturreduktion wird als wesentlicher Nachteil der extraoralen Zugänge die Gefahr einer[for full text, please go to the a.m. URL], 131. Kongress der Deutschen Gesellschaft für Chirurgie

(2008).

Bund und Länder beabsichtigten zu Beginn der 1980er Jahre, ein Informationszentrum als zentrale Einrichtung für Information und Dokumentation (IuD) im Bereich Geisteswissenschaften einzurichten. Es sollte in einer Testphase geklärt werden, in welcher Form und Größenordnung eine zentrale IuD-Einrichtung (sog. "Informationszentrum") in diesem Bereich organisiert werden kann. Dabei stand vor allem die Frage der Erarbeitung eines auch längerfristig haushaltsfähigen Konzeptes des Informationszentrums im Vordergrund, insbesondere die zu erwartenden Selbstfinanzierungsmöglichkeiten und die entsprechend benötigte Fehlbedarfsfinanzierung aus Mitteln der öffentlichen Hand. The paper describes investigations into the establishment of a central institution for information and documentation in the humanities, esp. its possible form and size.

The 8th European Particle Accelerator Conference, EPAC2002, Paris, France, 3 Jun 2002 - 7 Jun 2002; 1727-1729 (2002)., RF sources have the advantage of a cleaner plasma and a longer lifetime compared to filament sources. Hminus Ions can be produced by RF driven volume sources. These sources are often designed with an internal antenna. A present example is the RF Hminus source for the spallation accelerator SNS. A similar source is considered for the European spallation source ESS. At DESY a new development took place. The internalantenna of the HERA RF Hminus source was replaced by an external RF coupling. This system has been running for more than 25 000 h without any degradation. This is a significant improvement compared to the 980 h average lifetime of internal antenna systems. In recent publications [1], [2] the RF coupling problem has been raised again. Six basic reasons are given why external RF coupling is superior to internal coupling.

19th International Linear Accelerator Conference, LINAC 98, Chicago, USA, 23 Aug 1998 - 28 Aug 1998; 59 pp. (1998)., During the winter shutdown 1997/98, the injection system of the H$^-$-Linac III was upgraded. At present two different kinds of H_-sources are operated at DESY. The new cesium-free rf ion source is planned to operate parallel to the magnetron ion source.In addition a new MEBT (Medium Energy Beam Transport line) between two distinct RFQ accelerators and the Alvarez accelerator of Linac III was installed to match the beam of each ion source to the Alvarez acceptance. This scheme makes it possible to operate either H_-source with the Alvarez linac with a miniumum of effort to switch from one to the other. The design of the transport line also facilitates the development and tests of newly proposed ion sources, for example deuterium and polarized proton sources.After assembly of the RFQs and ion sources as well as the new components for the MEBT, a relatively easy commissioning could be demonstrated, although the ions have to be transported on a long distance from the RFQ to the Alvarez linac. First results of measurements will be presented.