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Solar power appears to be one of the most promising resources to meet the medium and long term renewable energy targets. The integration of large amounts of photovoltaic (PV) generation into distribution networks faces some limitations due to the network constraints. The PV community became well aware of these limitations in the last years. While first solutions have been pointed out mainly for large installations connected to the medium voltage network, the specificities of low voltage networks are still not fully understood. This paper aims at explaining the challenges associated to the planning and operation of low voltage network with high PV penetration. The actual impact of PV infeed is quantified on the basis of real and accurate network, load and generation data. Results from unsymmetrical load-flow computations are presented and the implementation of reactive power-based voltage control is shortly discussed. 26th European Photovoltaic Solar Energy Conference and Exhibition; 4469-4478

Exhaust hoods are commonly used to capture all emissions from stationary combustion systems that are open to the environment, such as residential heaters or stoves. For experimental purposes, emissions are sampled at one, or more, discrete locations downstream in the exhaust duct. Point-wise measurements in the duct are often taken with the assumption that the emissions are homogeneously distributed across the duct cross-section, because the flow is turbulent and therefore believed to be thoroughly mixed. However, the length of such systems is rarely sufficient to ensure fully-developed flow, and the actual homogeneity is seldom assessed. In the present work the mixing within the duct is investigated by simulating the emissions distribution within various hood and duct configurations. The simulations include a straight duct with and without baffles and two different exhaust hood configurations, namely at the Stove Testing Lab at Lawrence Berkeley National Laboratory (LBNL) and at the University of Adelaide that meet standard requirements. The air flow in the ducts was simulated using Reynolds-averaged (RANS) turbulence modelling, with carbon monoxide (CO) as a representative combustion product, injected at three locations in the straight duct and two locations (centre and side) in the exhaust hoods. Simulations predict that, in isolation, neither a straight duct without baffles, nor a hood with a 90° elbow followed by a straight duct without baffles, provide sufficient mixing to achieve a near uniform distribution of CO at the sampling locations. However, simulations show that adequate mixing of dilution air and CO is achieved with baffles-induced flow detachment and recirculation, not from turbulent mixing in the straight section of the duct itself. The simulations also suggest that elbows, baffles, expansions or other geometrical features are needed to induce thorough mixing. For example, in the Stove Testing Lab at LBNL, flow disturbance is induced by an expansion into a larger diameter straight duct immediately downstream of the hood and the 90° elbow. Although these two systems demonstrate sufficient mixing of CO within the exhaust, the RANS simulations in this study suggest that other systems relying solely on mixing within a specified duct length (viz. 8–12 diameters) may not be sufficient. Refereed/Peer-reviewed

The importance of wind energy has progressed rapidly in the last years. Although Horizontal Axis Wind Turbines (HAWT) are most well-spread, there is an increasing interest in Vertical Axis Wind Turbines (VAWT), especially in the H-Darrieus concept, as these rotors are omni-directional and affordable. However, the physics of these rotors is more complex; they can only be analyzed using transient CFD simulations. Due to the finite aspect ratio of the rotors, a wingtip vortex is created, which generates losses. Optimizing the wingtip geometry could be advantageous for increasing the efficiency of the rotors: this can only be achieved with three-dimensional turbulent transient simulations. For the optimization of winglets, the whole process (mesh generation, CFD computation, post-processing) has to be automated. This is achieved using the OPtimization Algorithm Library++ (OPAL++), a custom C++ code for the description of blended and canted winglets, coupled with a CD-Adapco StarCCM+ JAVA script for the automatization of the mesh generation and CFD computations. To check the viability of the present concept, two parameters have been varied in the simulations. As shown in what follows, an efficient automatic optimization of wind turbine wingtips can be implemented in this manner.

Increasing agricultural productivity is one of the most important aims of modern biotechnology. One way to enhance the productivity of crop species is to enhance the efficiency of photosynthesis. In C3 plants the oxygenase activity of Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) limits the photosynthetic efficiency. The green microalgae Chlamydomonas reinhardtii has evolved a CO2 concentration mechanism (CCM) by increasing the CO2 concentration in the chloroplast stroma where RuBisCO is located. Four independent transgenic tobacco genotypes (LA, LB, C1 and C3) were generated producing the low CO2-inducible protein A and B (LCIA and LCIB) or the carbonic anhydrases I and III (CAH1 and CAH3) from C. reinhardtii CCM in the envelope, stroma, intermembrane space or thylakoid lumen of tobacco chloroplasts, respectively. All four recombinant proteins were active in planta, which had a substantial impact on carbon and nitrogen metabolism. Increasing the CO2 concentration near RuBisCO resulted in an enhanced rate of photosynthesis (by up to 15%), efficiency of photosystem II (by up to 18%) and chlorophyll content (by up to 19%). Although to differing extents, all four transgenic genotypes grew faster than wild-type plants, produced more shoot biomass (up to 45% more fresh weight or 38% more dry weight in the LA lines) and accumulated more photosynthetic end products, reflecting the higher rate of photosynthetic CO2 fixation. The proteome analysis revealed that the proteins changed in the transgenic genotypes compared to the wild-type plants were primarily associated with the regulation of the Calvin cycle and the amino acid biosynthesis. Metabolic analysis of the transgenic LA, LB and C3 plants revealed an increase in the levels of carbohydrates and also of most amino acids. Furthermore, transgenic LA and LB plants could maintain the enhanced biomass under low nitrogen conditions, where similarly-treated wild-type plants grew more slowly. The data generated in the present study confirmed that even single Chlamydomonas CCM components can be integrated into C3 plants to increase biomass, suggesting that transgenic lines combining multiple components or even a complete CCM could further increase the productivity and yield of C3 crops. RWTH Aachen University, Diss., 2017; Aachen, 1 Online-Ressource (151 Seiten) : Illustrationen, Diagramme(2017). = RWTH Aachen University, Diss., 2017 Published by Aachen

This Article examines the genesis and context of SE4All, placing the effort within both itshistorical and international policy contexts. It highlights the voluntary nature of the initiative andargues that its effective implementation and the achievement of its goals require the articulation ofan applicable international legal framework that aids the transformation of SE4All’s policy actionsinto binding international legal commitments. The article contends that such a transformation doesnot depend on the creation of entirely new legal rules or institutions. Instead, an effective frame-work for successful implementation of SE4All can be derived from existing rules of internationalhuman rights law and sustainable development law. Reliance on these twin bodies of interna-tional law will increase the prospects for SE4All to achieve energy access and related goals thatits predecessor initiatives have failed to accomplish

Available online 13 October 2023 ; Rising demand for protein-rich foods can impact N₂O emissions from croplands. Recent research has pointed to the role of modified plant vasculature in grain protein increase. Here we highlight how discovering the mechanistic role of plant vasculature in protein improvement and nitrogen-use efficiency could reduce global N₂O emissions. ; Luqman B. Safdar, Ian D. Fisk, and M. John Foulkes

The desire to reduce fuel consumption and gas emissions, along with increasing demands on electrical energy is driving the evolution of vehicle power system architectures well beyond the conventional single alternator and battery. Amongst the different power system architectures available, are mild-hybrid electric architectures. Such architectures may offer flexibility in balancing the trade-offs associated with minimising fuel consumption, and greater capacity to meet electric energy demands. They allow for a wide range of energy management strategies to be investigated. Such strategies are able to accommodate for the need to reduce fuel consumption, undesirable gas emissions, and the need to meet the increased dependence on electrical energy. The strategies can be implemented by vehicle power management systems running energy management algorithms. Such systems are becoming more common in commercial vehicles, however, they are not commonly found in current military vehicles. This thesis focusses on evaluating the impacts caused to vehicle acceleration, fuel consumption, the time to fully charge/discharge the vehicle battery pack, and the electrical conversion efficiency, when introducing energy management strategies into a baseline mild-hybrid electric combat vehicle under different military stationary and moving scenarios. The scenarios were selected because current vehicle manufacturers and academia have primarily focussed on investigating energy management strategies in urban environments. In comparison, a study involving military scenarios allows a new application domain to be investigated. The thesis describes the mild-hybrid electric combat vehicle baseline, and presents the results of comparing the baseline against one that has been extended to include additional energy management strategies under different military scenarios. ; Thesis (MPhil) -- University of Adelaide, School of Electrical and Electronic Engineering, 2018

Marine ecosystems are known to be climatea dependent, and impacts from progressing global climate change are increasingly observed and anticipated to intensify in the course of the 21st century. Under continuously high anthropogenic greenhouse gas emissions, drivers such as ocean warming, ocean acidification, and deoxygenation will increasingly affect marine ecosystems and the provision of marine ecosystem services to human societies. Environmental drivers affect organismal processes directly, but also have indirect effects through biotic interactions. Human societies are dependent on the ecosystem services provided by the oceans, and have limited adaptive capacities to changes in ecosystem service provision. An integrated evaluation of marinea human systems is thus necessary to understand coming changes, and is increasingly pursued by recent ecosystema based and integrated assessment and management approaches. The uncertainty of future climate change impacts and the interactions with the increasing anthropogenic pressures on marine systems need to be addressed. Ecological models are important tools to provide this integration of data and processes, as they can put experimental and observational data into context, and enable us to move beyond simple extrapolations of future states and experiences, creating an understanding of the changes in marine ecosystems anticipated in the future. While a wide variety of modeling approaches is available to answer specific ecological questions, a quantitative integration over different hierarchical levels, and different types of data and knowledge, is rarely achieved. The presented thesis revolves around a case study from the Barents Sea, which is among the marine regions with the earliest impacts of ocean acidification and warming expected and already observed, providing an integrative view of the impacts of these drivers on marine ecosystems and the provision of ecosystem services in the focus region. The work was built upon a thorough general analysis of available modeling approaches for modeling climate change impacts on marine fish populations (Paper 1). This analysis assessed capacities of the existing modeling approaches and recent applications, and revealed processes which need to be incorporated better in the light of recent experimental and observational results. A modeling framework to address the specific questions in the Barents Sea region was developed based on participation of stakeholders gained during personal interviews and two workshops (Paper 2). This served to incorporate their concerns and knowledge into the model structure and identify potential adaptation options for the stakeholder groups. To address one specific scientific question of high importance and uncertainty, the anticipated impacts on fish stock recruitment, an early life stage model was developed which incorporates the experimentally quantified effects of ocean acidification and warming on Atlantic cod eggs and larvae (Paper 3). This model offers a new approach to integrating empirical data on environmental and food-web drivers into recruitment projections of marine fish. Finally, an integrative fooda web model based on the structure developed in the stakeholder work and on current processa based understanding was parameterized with empirical data and estimates of organismal rates, to simulate the dynamic fluctuations in the Barents Sea food web and explore potential shifts in composition and dynamics under ocean warming and ocean acidification (Paper 4). In the thesis discussion, the papers are summarized and put into context, and the implications for the user groups in the region and possible societal adaptation options to the projected changes are highlighted. Impacts on fisheries, cultural and recreational ecosystem services, associated adaptation options for stakeholder groups, and interactions with other uses of the ocean system and expected changes under climate change are delineated. To advance ecosystema based governance in the area, the limitations in adaptation options of some user groups point to the need to better consider these groups in decisions and regulations concerning fisheries and marine areas. The Barents Sea study thus exemplifies the possibilities to integrate experiments, observations and stakeholder input into integrative assessments of marine ecosystems under climate change. Based on the insights gained from processa based modelling and stakeholder participation, it is described how understanding and projections of climate change impacts on marinea human systems can be advanced, pointing out the importance of improved interdisciplinary cooperation and communication and an integrative perspective to link across scales and subsystems a tasks to which purposefully designed models can contribute substantially.

Bio-based and biodegradable plastics (BBPs) are innovative materials, wholly or partially produced from biomass, with the potential to enhance the circulation of resources in the biological cycle of the Ellen MacArthur Foundation’s butterfly diagram. Although BBPs are generally considered more environmental-friendly than conventional plastics, robust scientific evidence is still missing. The lack of tools and metrics to assess the circularity and sustainability of the BBPs industry poses relevant challenges for its upscaling and contribution to climate neutrality goals in Europe. It calls for adopting system and life cycle thinking, guided by multi-level and multi-dimensional examinations, which led researchers to build a comprehensive picture of trends, gaps and future orientations that may boost a sustainable circular bioeconomy in the sector. The value- chain based and multi-faceted SWOT analysis that emerged from the intersection of system and corporate data reveals the need to establish a combined circular bioeconomy strategy where incentives to integrated local supply chain, dedicated EPR scheme, eco-design guidelines, revised EoL standards, new clear labelling schemes and harmonised sustainability criteria should be prioritized and conjointly pursued to accelerate the transition towards a sustainable circular bioeconomy of the BBPs value chain. European Journal of Social Impact and Circular Economy, V. 4 N. 2 (2023)