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The use of microalgae culture to convert CO2 from power plant flue gases into biomass that are readily converted into biofuels offers a new frame of opportunities to enhance, compliment or replace fossil-fuel-use. Apart from being renewable, microalgae also have the capacity to utilise materials from a variety of wastewater and the ability to yield both liquid and gaseous biofuels. However, the processes of cultivation, incorporation of a production system for power plant waste flue gas use, algae harvesting, and oil extraction from the biomass have many challenges. Using SimaPro software, Life cycle Assessment (LCA) of the challenges limiting the microalgae (Chlorella vulgaris) biofuel production process was performed to study algae-based pathway for producing biofuels. Attention was paid to material use, energy consumed and the environmental burdens associated with the production processes. The goal was to determine the weak spots within the production system and identify changes in particular data-set that can lead to and lower material use, energy consumption and lower environmental impacts than the baseline microalgae biofuel production system. The analysis considered a hypothetical transesterification and Anaerobic Digestion (AD) transformation of algae-to- biofuel process. Life cycle Inventory (LCI) characterisation results of the baseline biodiesel (BD) transesterification scenario indicates that heating to get the biomass to 90% DWB accounts for 64% of the total input energy, while electrical energy and fertilizer obligations represents 19% and 16% respectively. Also, Life Cycle Impact Assessment (LCIA) results of the baseline BD production scenario show high proportional contribution of electricity and heat energy obligations for most impact categories considered relative to other resources. This is attributed to the concentration/drying requirement of algae biomass in order to ease downstream processes of lipid extraction and subsequent transesterification of extracted lipids into BD. Thus, four prospective alternative production scenarios were successfully characterised to evaluate the extent of their impact scenarios on the production system with regards to lowering material use, lower energy consumption and lower environmental burdens than the standard algae biofuel production system. A 55.3% reduction in mineral use obligation was evaluated as the most significant impact reduction due to the integration of 100% recycling of production harvest water for the AD production system. Recycling also saw water demand reduced from 3726 kg (freshwater).kgBD- 1 to 591kg (freshwater).kgBD- 1 after accounting for evaporative losses/biomass drying for the BD transesterification production process. Also, the use of wastewater/sea water as alternative growth media for the BD production system, indicated potential savings of: 4.2 MJ (11.8%) in electricity/heat obligation, 10.7% reductions for climate change impact, and 87% offset in mineral use requirement relative to the baseline production system. Likewise, LCIA characterisation comparison results comparing the baseline production scenarios with that of a set-up with co-product economic allocation consideration show very interesting outcomes. Indicating -12 MJ surplus (-33%) reductions for fossil fuels resource use impact category, 52.7% impact reductions for mineral use impact and 56.6% reductions for land use impact categories relative to the baseline BD production process model. These results show the importance of allocation consideration to LCA as a decision support tool. Overall, process improvements that are needed to optimise economic viability also improve the life cycle environmental impacts or sustainability of the production systems. Results obtained have been observed to agree reasonably with Monte Carlo sensitivity analysis, with the production scenario proposing the exploitation of wastewater/sea water to culture algae biomass offering the best result outcome. This study may have implications for additional resources such as production facility and its construction process, feedstock processing logistics and transport infrastructure which are excluded. Future LCA study will require extensive consideration of these additional resources such as: facility size and its construction, better engineering data for water transfer, combined heat and power plant efficiency estimates and the fate of long-term emissions such as organic nitrogen in the AD digestate. Conclusions were drawn and suggestions proffered for further study.

The 2022 World Cup organised by the International Association Football Federation (International Olympic Committee, 2021) and hosted by Qatar was billed to be the tournament that would completely revolutionise football, both on and off the field. It garnered acclaim in being the first World Cup held outside its customary months of June-July as well as in pioneering net zero carbon emissions in the sport - an assertion that ultimately proved largely unfounded(Ralston, 2022) with high reputational consequences for the country and the game. Non-governmental organisations (NGOs), like the Carbon Market Watch that works with the European Union amongst others, claimed that “carbon emissions created by the new stadiums could be as much as eight times higher than the figures contained in Qatar’s analysis” (MacInnes, 2022). Against the backdrop of mounting sustainability concerns expressed by policymakers and enthusiasts alike, this essay examines the environmental hazards associated with major sporting events, like the 2022 FIFA World Cup whilst delving into adaptations that organisers could make for future sporting bonanzas that would give their green aspirations wings that could fly without getting burned like the fabled Icarus whose own pride and arrogance led him to ignore the rising temperatures and ultimately cause his demise. Essex Student Journal Volume 14 Issue S1 2023

Wave energy is an important renewable energy source. Previous studies of wave energy conversion (WEC) have focused on the maximum power take-off (PTO) techniques of a single machine. However, there is a lack of research on the energy and power quality of wave farm systems. Owing to the pulsating nature of ocean waves and popular PTO devices, the generated electrical power suffers from severe fluctuations. Existing solutions require extra energy storage and overrated power converters for wave power integration. In this study, we developed a master-slave wave farm system with rotor inertia energy storage; this system delivers self-smoothed power output to the grid and reduces the number of converters. Two control methods based on the moving average filter (MAF) and energy filter (EF) are proposed to smooth the output power of wave farms. RTDS simulations show that the proposed systems and control methods facilitate simple and smooth grid integration of wave energy. Keywords: Wave farm, Energy storage, Power smoothing, Power quality, Energy quality

A fundamental change in societal values and economic structures is required to address increasing pressures on ecosystems and natural resources. Transition research has developed in the last decades to analyze the co-dynamics of technological, institutional, social and economic elements in the provision of key functions such as energy, water and food supply. This doctoral dissertation provides conceptual and methodological contributions to the pro-active governance of sustainability transitions. Three research gaps are identified that are addressed in this dissertation. First, a comprehensive conceptualization of learning in sustainability transitions is currently missing that comprises learning at multiple societal levels (ranging from individuals to policy-actors). Learning concepts are often not explicitly discussed in transition research even though learning is considered as fundamental for innovation processes, niche formation and development as well as breakthrough and diffusion of innovations. Second, methods for the analysis and design of transition governance processes are lacking that specify case-specific intervention points and roles of actors in the implementation of innovations. Third, participatory modeling approaches are only applied to a limited extent in transition research despite a high potential for supporting communication and learning. The conceptualization of multi-level learning developed in this doctoral research conceptualizes learning at different societal levels as specific learning contexts ranging from individual and group contexts to organizational and policy contexts. The conceptual framework further differentiates between learning processes, intensity, objects, outcomes, subjects and factors, allowing for a more detailed analysis of learning within and across learning contexts. Thus, learning contexts can be linked by processes that involve actors from different learning contexts (e.g., community groups and policy-makers), as well as exchanges of physical aspects, institutions ...

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

Given the highly climate-sensitive character of agricultural production, climate change has obvious and important ramifications for agricultural commercialisation, which in turn has a bearing on poverty, gender empowerment, and food and nutrition security. The nature and extent of climate change implications for agricultural commercialisation will depend on: the magnitude of the climate impacts that farmers have to deal with; and, the extent to which sustainable intensification processes can be pursued in ways which strengthen, rather than weaken, adaptive capacity and resilience in the face of climate change. This brief provides a summary of a longer working paper, which offers a review of recent literature on the implications of climate change for agricultural commercialisation and APRA’s research in this area.

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

Devon County Council