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Xiyu Ren is a DPhil candidate at the Smith School of Enterprise and the Environment, the School of Geography and the Environment, and the Institute for New Economic Thinking at the Oxford Martin School of the University of Oxford. Her research interests lie in energy and environmental economics, particularly in energy modeling, electricity market design, times-series analysis, and environmental policies. Iacopo Savelli is a postdoctoral researcher in applied economics at the GREEN Centre, Bocconi University. He is the PI of the peer-reviewed project “Decarbonising the energy system by incentivising energy storage in the right places,” investigating the role of grid-scale energy storage in decarbonizing the energy system. Previously, he was a postdoc at the University of Edinburgh and the University of Oxford working on energy market design. He holds a PhD in engineering, an MS in finance, and a BS in economics. He taught selected energy economics topics at the University of Oxford and the University of Siena. Thomas Morstyn is associate professor in power systems with the Department of Engineering Science of the University of Oxford, where he leads a research group focused on power system control and energy market design. He is also a tutorial fellow at Hertford College and an honorary fellow at the University of Edinburgh. He is an associate editor of IEEE Transactions on Power Systems and co-chairs the IEEE Power & Energy Society Taskforce on Quantum Computing for Power System Operations. His research focuses on the design of control systems and markets to enable the large-scale integration of distributed power system flexibility.

Power system controls are vulnerable to cyber-attacks that can seriously affect and even inhibit their operation. Such attacks may affect large portions of the power system, make repair difficult and cause huge societal impact, so pressure to ensure cyber-security of control and communication systems is now strong worldwide. Several cyber-security frameworks were developed, but it is rather difficult to anticipate adoption costs and benefits, and this hampers their generalised adoption. T his paper focuses on the outcome of two case studies (concerning the Italian power generation and the Polish transmission systems. The socio-economic impact of failures and the costs of standard adoption are estimated on an objective basis. It is up to public authorities to decide whether to require the adoption of security standards to operators in the electric system. The nature of public good of security underlines the necessity of public support for this operation, but we discuss the extent and the management of this support.

Ammonia is a promising clean and sustainable energy carrier, yet challenges persist in achieving stable combustion, particularly concerning poor ignition quality and elevated NOx emissions. Recent research suggests that the Moderate or Intense Low-oxygen Dilution (MILD) regime could address these challenges for ammonia combustion. This study aims to optimize the MILD regime using non-equilibrium plasma discharges, specifically nanosecond repetitive pulsed discharges (NRPD). While the beneficial effects of NRPD on ammonia chemistry have been demonstrated in traditional applications, their impact under the highly diluted conditions characteristic of the MILD regime remains unexplored. This numerical study employs a detailed two-temperature model to investigate the effects of pulsed discharges in ammonia/air mixtures, simulating conditions representative of the MILD regime. The research comprehensively explores the selection of optimal discharge settings and examines plasma effects on various parameters, including ignition delay time, flammability limit, radical production, and emissions. Equivalence ratios ranging from 0.2 to 2 and dilution levels up to 2.5% O2 are considered in this investigation. Results indicate that NRPD show a notable benefit by enlarging fuel-lean and fuel-rich stability limits, promising enhanced operational flexibility. Examining OH radicals and NOx emissions underscored a consistent plasma-driven mechanism, reducing emissions, also in the MILD regime. Novelty and Significance Statement The novelty of this research is the application of non-equilibrium plasma discharges to improve ammonia combustion in the MILD regime. It offers a new and original solution to the challenges associated with the poor ignition quality and high NOx emissions that are currently limiting its practical implementation. For the first time, a numerical analysis is provided to quantify the benefits of plasma chemistry activation on the combustion performance. Another novel aspect of this work is the use of a detailed two-temperature model to describe the plasma-combustion interactions in an integrated computational framework. The literature reports only a few references on the interaction of plasma with MILD combustion conditions. The former were modeled using a very simplified model to describe the evolution of the plasma species. Consequently, we believe that this contribution will significantly advance the state-of-the-science in field of plasma-assisted ammonia combustion.

Additional efforts will be needed by European countries to improve the energy efficiency, as with current trends the 20% objective will be missed. Small and medium-sized enterprises (SMEs) manufacturing sector is a promising field, as SMEs are less energy-efficient than larger enterprises. Several studies investigated the barriers to the diffusion of technologies and practices for industrial energy efficiency, but little attention has been paid to understand the factors affecting the perception of such barriers by SMEs. In this multiple case-study, we have investigated 20 Primary Metal manufacturing SMEs in Northern Italy. Economic and information barriers are perceived as the major issues. Interestingly, firm's size, innovativeness of the market in which enterprises operate, as well as product and process innovation are factors affecting barriers to energy efficiency. Differences have been observed within SMEs, especially for information and competence-related barriers. In particular, a more innovative external context in which enterprises operate and a greater production process complexity seem to reduce barriers. Moreover, more product innovative enterprises seem to have a lower perception of behavioral and technology-related barriers. The results of this exploratory investigation provide useful suggestions for policy design and further research on industrial energy efficiency.

Silicon carbide/silicon rich carbide multilayers, aimed at the formation of silicon nanodots for photovoltaic applications, have been studied. The electrical properties have been investigated at the nano-scale by conductive Atomic Force Microscopy (c-AFM) and at macro-scale by temperature dependent conductivity measurements. The mixture is composed of highly conductive Si nanoclusters and moderately conductive SiC nanoclusters in a disordered matrix. The conduction mechanism takes place via band states induced by the disorder at the interface between nanodot clusters. Structural properties have been extracted by optical spectroscopy analyses. The results contribute to the understanding of the microscopical electronic mechanisms of the composite material, which is a candidate for third generation photovoltaics.

Abstract In principle, absorption chillers of the ammonia-water type could work at temperatures well below the usual air-conditioning temperatures, arriving at the range 250–260 K, which can be useful for refrigeration applications. This possibility is studied for an air-cooled machine, comparing the results with the experimental data supplied by a manufacturer that recently commercialized such a refrigerator. The prediction is fair, and the study allows an insight into the internal parameters and into the possible behaviour for more severe conditions than those studied.

Self-organizing nanopatterns can enable economically competitive, industrially applicable light-harvesting platforms for thin-film solar cells. In this work, we present transparent solar cell substrates having quasiperiodic uniaxial nanowrinkle patterns with high optical haze values. The self-organized nanowrinkle template is created by controlled heat-shrinking of metal-deposited pre-stretched polystyrene sheets. A scalable UV nanoimprinting method is used to transfer the nanopatterns to glass substrates on which single-junction hydrogenated amorphous silicon p-i-n solar cells are subsequently fabricated. The structural and optical analyses of the solar cell show that the nanowrinkle pattern is replicated throughout the solar cell structure leading to enhanced absorption of light. The efficient broadband light-trapping in the nanowrinkle solar cells results in very high 18.2 mA/cm2 short-circuit current density and 9.5% energy-conversion efficiency, which respectively are 35.8% and 39.7% higher than the values obtained in flat-substrate solar cells. The cost- and time-efficient technique introduces a promising new approach to customizable light-management strategies in thin-film solar cells.

Although nearly zero energy buildings have attracted growing research attention, literature analysis shows that only a limited number of researches try to couple load match/grid interaction issues and environmental impacts in early design stages. The study proposes a novel multidisciplinary design approach that allows to integrate these two conflicting aspects aiming to find trade-offs. The proposed approach has been applied to a building case study, equipped with a photovoltaics system without energy storage. The results show that even though on yearly basis the energy use (5,290 kWhe) is largely overcome by the on-site energy generation (8069 kWhe), an oversized PV system alone may not be the best solution for reducing the environmental impact of the building sector, besides not being very efficient in improving load match. Afterwards, a parametric analysis was carry out analysing three redesign scenarios, obtained varying the sizes of the PV system and installing different sizes of the storage systems. The results show that the use of storage systems, in addition to decrease the grid dependency, can increase the environmental benefits arising from the renewable energy sources (e.g. there is a decrease of global warming potential of 48%, compared to the base case, with 5.28 kWp PV system and 10 kWh storage system). Conflicting results are found according to specific impact categories and this suggests the need for a holistic approach, including different domains and indicators. In this context, the proposed approach can contribute to the transition toward low-carbon energy technologies, by supporting researches and designers to take environmentally sound considerations.