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Editorial Complex Optimization and Simulation in Power Systems

Energy storage systems can improve the uncertainty and variability related to renewable energy sources such as wind and solar create in power systems. Aside from applications such as frequency regulation, time-based arbitrage, or the provision of the reserve, where the placement of storage devices is not particularly significant, distributed storage could also be used to improve congestions in the distribution networks. In such cases, the optimal placement of this distributed storage is vital for making a cost-effective investment. Furthermore, the now reached massive spread of distributed renewable energy resources in distribution systems, intrinsically uncertain and non-programmable, together with the new trends in the electric demand, often unpredictable, require a paradigm change in grid planning for properly lead with the uncertainty sources and the distribution system operators (DSO) should learn to support such change. This paper considers the DSO perspective by proposing a methodology for energy storage placement in the distribution networks in which robust optimization accommodates system uncertainty. The proposed method calls for the use of a multi-period convex AC-optimal power flow (AC-OPF), ensuring a reliable planning solution. Wind, photovoltaic (PV), and load uncertainties are modeled as symmetric and bounded variables with the flexibility to modulate the robustness of the model. A case study based on real distribution network information allows the illustration and discussion of the properties of the model. An important observation is that the method enables the system operator to integrate energy storage devices by fine-tuning the level of robustness it willing to consider, and that is incremental with the level of protection. However, the algorithm grows more complex as the system robustness increases and, thus, it requires higher computational effort.

In hot climates, ventilated pitched roofs help dissipating the excess heat, thus reducing the cooling energy demand. The key factor is the so-called Above Sheathing Ventilation (ASV) that depends on the air entering and leaving at the eaves, ridge and the gaps among tiles. A strategy for increasing the ASV is the enhancement of the roof air permeability through the development of new tile shapes, as proposed in the European Life HEROTILE project. The performance of a ventilated pitched roof are experimentally analysed by comparing some covering options: the new tile shape designs against the standard ones, available in the market, and a metal cover. A real scale pitched roof mock-up was built and equipped with a comprehensive monitoring system. The air flow and temperature in the different roof layers, as well as the heat flux passing through the roof and the cooling energy demand, were monitored according to the local weather conditions during the summer season. The analysis showed that the new tile design increases the ASV in comparison with the standard ones, and better thermal performance was achieved by reducing the heat gain due to solar radiation.

Recent calls to do climate policy research with, rather than for, stakeholders have been answered in non-modelling science. Notwithstanding progress in modelling literature, however, very little of the scenario space traces back to what stakeholders are ultimately concerned about. With a suite of eleven integrated assessment, energy system and sectoral models, we carry out a model inter-comparison for the EU, the scenario logic and research questions of which have been formulated based on stakeholders' concerns. The output of this process is a scenario framework exploring where the region is headed rather than how to achieve its goals, extrapolating its current policy efforts into the future. We find that Europe is currently on track to overperforming its pre-2020 40% target yet far from its newest ambition of 55% emissions cuts by 2030, as well as looking at a 1.0-2.35 GtCO2 emissions range in 2050. Aside from the importance of transport electrification, deployment levels of carbon capture and storage are found intertwined with deeper emissions cuts and with hydrogen diffusion, with most hydrogen produced post-2040 being blue. Finally, the multi-model exercise has highlighted benefits from deeper decarbonisation in terms of energy security and jobs, and moderate to high renewables-dominated investment needs.

Abstract Highly performing activated biochar-based catalysts were produced for steam reforming of slow pyrolysis oil. The raw biochar obtained from the slow pyrolysis step was physically activated with CO2 at 700 °C and 1.0 MPa and then employed as support. Preliminary tests on steam reforming of acetic acid at 600 °C showed that using activated biochar-supported catalysts containing 10 wt % Ni and 7 wt % Co led to a conversion above 90% with a relatively slow deactivation rate. When a representative organic model compounds mixture was used as feed, relatively fast deactivation of the catalyst was observed, probably due to the adsorption of heavy organic compounds, which could subsequently react to form not easily desorbable reaction intermediates. However, the dual Ni–Co catalysts exhibited a good performance during the steam reforming of a real slow pyrolysis oil at 750 °C, showing long stability and a constant carbon conversion of 65%.

The increasing adoption of solar power plants requires the consideration of different aspects involved in the transformation of landscape. In this view, recent studies encourage public engagement and landscape integration strategies in the decision-making process to ensure an accepted and inclusive energy transition. However, there is limited knowledge on how to include landscape considerations in the planning processes, specifically on public perception and values. This work aims to assess five licensed solar farms in the region of Central Macedonia (Greece) based on the opinion of the inhabitants. The paper presents the results of an online and onsite questionnaire administered in different villages around the study area in October 2022. The survey utilized the potential benefits and impacts, as well as siting criteria and spatial configuration strategies, taken from literature to describe public perception and preferences. The methodology consists of three phases: investigation of public perception on solar farms; operationalization of the results to make them spatially explicit; overall suitability of the areas and mitigation strategies. The results illustrate the prioritization of the perceived impacts and benefits of photovoltaic installations and highlight the different levels of suitability of the areas and possible mitigation measures. The proposed approach is complementary to the planning processes taking into account societal considerations.