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Abstract This paper focuses on the study of an electricity market model, which evolves in T+1 stages, so that, at each stage, a continuum state of nature is possible. The decision-making framework of large consumers is considered: agents consume, they have the opportunity to produce, and the capability of signing contracts. Uncertainty on future possible stages leads to the problem being located in a filtered probability space. The aim is to reformulate the problem as a stochastic quasi-variational inequality, in order to obtain an existence result of equilibrium solutions.

Cereals, staple crops in human nutrition, are called to face manifold challenges to encounter the urgent demand of food along with a higher nutritional value ensuring the sustainability of the supply chain. In this view, research focuses on two main topics; firstly, the rise in productivity, balancing the growing demand of food, consistent with the availability of environmental resources. The second issue regards the urgency to properly cover the nutritional needs of the population which has become more sensitive to pathologies related to high-calorie eating habits and poor in valuable nutritional compounds. Faced with such important issues, it is desirable to adopt a full approach, based on projects aimed at satisfying multiple requests at once. The research here discussed concerns the development of three durum wheat genotypes in which novel properties have been combined both in the health-functional profile of the derived foods and in the milling characteristics of the grain. The project involves a group of durum wheat genotypes, in which the starch component has been modified in the amount of amylose, a polysaccharide that, together with amylopectin, constitutes the reserve starch. The high amylose genotypes are of interest due to the low glycemic profile and the prebiotic functionality of the derived foods depending on the increase in "resistant starch"; the amylose-free genotype is suitable for the design of highly digestible foods ideal for specific uses, such as nutrition for infants. These genotypes were, therefore, the subject of a further improvement breeding program focused on modifying the hardness of the seed associated with the efficiency and sustainability of grinding and the quality of the final products. In detail, three different genotypes of durum wheat have been selected:1) Soft Svevo /Sv SSIIa and 2) Soft Svevo/Sv SBEIIa combine a high amylose content with a softer kernel that results in increased resistant starch content and energy saving during the milling process. The third genotype, Soft Svevo/Sv Waxy, combines a softer kernel with free amylose starch following a novel starch digestibility profile suited for specific food categories. A marker-assisted selection based on HRM-genotyping has been performed to identify the homozygous mutants in the progenies of the three different crosses. Biochemical analyses such as the determination of total starch, resistant starch, starch damage, ?-glucan and arabinoxylan content are in progress and will be able to highlight the potential value of the selected genotypes.

The potential for global forest cover The restoration of forested land at a global scale could help capture atmospheric carbon and mitigate climate change. Bastin et al. used direct measurements of forest cover to generate a model of forest restoration potential across the globe (see the Perspective by Chazdon and Brancalion). Their spatially explicit maps show how much additional tree cover could exist outside of existing forests and agricultural and urban land. Ecosystems could support an additional 0.9 billion hectares of continuous forest. This would represent a greater than 25% increase in forested area, including more than 200 gigatonnes of additional carbon at maturity.Such a change has the potential to store an equivalent of 25% of the current atmospheric carbon pool. Science , this issue p. 76 ; see also p. 24

Artículos en revistas Numerical models of transmission-constrained electricity markets are used to inform regulatory decisions. How robust are their results? Three research groups used the same data set for the northwest Europe power market as input for their models. Under competitive conditions, the results coincide, but in the Cournot case, the predicted prices differed significantly. The Cournot equilibria are highly sensitive to assumptions about market design (whether timing of generation and transmission decisions is sequential or integrated) and expectations of generators regarding how their decisions affect transmission prices and fringe generation. These sensitivities are qualitatively similar to those predicted by a simple two-node model. info:eu-repo/semantics/publishedVersion

Abstract In the field of innovative power sources, photovoltaic are playing an important role as new clean energy generators. The performances being dependent on instantaneous weather condition, photovoltaic sources are usually equipped with an auxiliary energy storage device. There are applications where the opportunity to couple the photovoltaic source with ultracapacitor can be taken into account. The aim of the paper is to study the performances of a hybrid system constituted by photovoltaic and ultracapacitor sources. In particular, the paper deals with the study of the ultracapacitor rate design for photovoltaic systems feeding pulsing loads. The results of the study, which can also be referred to temporary unfavourable weather conditions, have been validated by experimental data. In the final part of the paper, some considerations on economical implications about the dimensioning of a photovoltaic–ultracapacitor systems are drawn.

Abstract In the last years, electric vehicles (EVs) are getting significant consideration as an environmental-sustainable and cost-effective alternative over conventional vehicles with internal combustion engines (ICEs), for the mitigation of the dependence from fossil fuels and for reduction of Green-House Gasses (GHGs) emission. However, many challenges are still ongoing to their large scale implementation. Among them, the negative impact on the electrical grid operation in case of an uncoordinated contemporary charging of a huge number of EVs. In the recent literature different solutions are proposed for handling the peak demand of EVs and the related problems. One answer is offered by the implementation of EV charging strategies, through aggregation agents, for containing the impact on the grid, guaranteeing the quality of the service. The implementation of a real charging strategy is strictly related to a deployment of smart-grid technologies, such as smart meters, Information and Communication Technologies (ICTs) and energy storage systems (ESSs). In particular ESSs are playing a fundamental role in the general smart grid paradigm, and can become fundamental for the integration in the new power systems of EV fast charging stations of the last generation: in this case the storage can have peak shaving and power quality functions and also to make the charge time shorter. In the present paper, an overview on the different types of EVs charging stations, in reference to the present international European standards, and on the storage technologies for the integration of EV charging stations in smart grid is reported. Then a real implementation of EVs fast charging station equipped with an ESS is deeply described. The system is a prototype, designed, implemented and now available at ENEA (Italian National Agency for New Technologies, Energy and Sustainable Economic Development) labs. A wide experimental activity has been performed on the prototype system in order to test its functionalities in the integration in a smart grid available at the same ENEA lab, including a smart metering system. The integration has been possible thanks to the use of a customized communication protocol, developed by the researchers and here described. The results of the experimental tests show that the system has a good performance in the implementation of peak shaving functions, in respect of the main distribution grid, making the prototype like a network nearly zero-impact system.

Abstract The organic Rankine cycle (ORC) has been growing in importance as a technology for producing electricity from low temperature waste and renewable heat sources. In small-scale applications, the most used working fluid has been HFC-245fa, although this is being substituted for low GWP alternatives. A new HCFO working fluid, HCFO-1224yd(Z), has appeared as a possible alternative for HFC-245fa. In this study, this alternative working fluid is analysed and, finally, the working fluid is experimentally tested as drop-in alternative in a commercial ORC system. The main purpose is to determine the feasibility of using HCFO-1224yd(Z) as a drop-in replacement for HFC-245fa in a real facility that was initially designed to operate with HFC-245fa. The results show how the use of HCFO-1224yd(Z) offers power output that ranges from 7.5% to 17.4% lower than that provided by HFC-245fa. Although HFC-245fa offers higher power output, the results show that HCFO-1224yd(Z) offers up to 7.7% higher cycle net efficiency; this is due to the higher input thermal rate required by HFC-245fa. Finally, HCFO-1224yd(Z) has been stated as a suitable alternative to HFC-245fa as a drop-in replacement in a small-scale, low-temperature ORC, which increases its attractiveness for heat source with higher temperatures.

Abstract Both steady-state AC and DC power flow models are commonly used for techno-economic studies of power systems. The DC-based approach limits the computational burden by assuming small-angle approximation, ignoring power losses, reactive power flows, and voltage variations. It, therefore, matters to understand if this approach affects system vulnerability, reliability, and contingency assessments. To this aim, we use the time-sequential Monte Carlo simulation and an N-k′-1 scenario for reliability and contingency analyses, respectively. Further, we introduce a new index for vulnerability assessment. The IEEE reliability test system (RTS) and the modified RTS are modeled. The results show that the DC model underestimates the reliability indices by about 20% and more than 90% in a stressed network. We also show a small error of 5%, owing to the assumptions of the DC model, which can lead to inaccurate simulations concerning the cascading failures. Finally, the sources of the inaccuracy in the DC-based model are investigated. The results prove that AC power flow model should be privileged for the line capacity-based assessments.