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Capítulos en libros In concert with increasing co-ordination of energy markets, transmission planning for location-constrained generation is forcing a shift from regional to wide-area transmission network planning. Planning for locationconstrained generators, notably wind and solar resources, is complicated by uncertainty in policies driving their growth. To design transmission systems robust to uncertain future expansion of location-constrained generators, planners must incorporate stochastic generation into models. The size of the transmission expansion problem makes this computationally intractable. This paper presents a screening model to reduce the number of transmission investments which must be considered. The screening model combines sampled generation expansion scenarios with a two-stage relaxed planning model to identify corridors of interest. A St.Clair curve-based filter translates corridors to investment variables. In a 240 bus model of WECC, this method reduced the number of corridors of interest 98% from 19,503 to 303 and reduces the number of investment variables 99% from 58,503 to 432. info:eu-repo/semantics/publishedVersion

A novel application of geopolymers for the catalytic cleaning of biomass-derived syngas is reported. Powders of metal oxides, i.e. Fe2O3 and Mn2O3, were dispersed in a geopolymer matrix, to produce composites in granular form for fixed bed application. Additionally, a mixed Fe/Mn composite was produced to explore the combined effects of the two oxides. The activity of the new catalysts was investigated in real gasification conditions by means of a double fixed bed reactor, at 700, 800 and 900 °C. All the systems promoted an appreciable tar removal, while FE-SEM and MIP analyses demonstrated their stability at the process conditions. The best performances were obtained using the composite including both Mn and Fe oxides, which registered a tar decomposition up to 86% compared to inert sand, and 50% compared to olivine. A reasonable explanation was provided by TPR and XRD analyses, which pointed out an easier reducibility of this system.

Artículos en revistas The studies reported in this paper describe models and evaluation techniques based on Monte Carlo simulation for the reliability assessment of mixed hydro-thermal generation systems. In particular it considers the effects that system operating and water management policies have on the reliability indices. These effects are described and discussed using the basic IEEE Reliability Test System (RTS) extended by additional hydro plant data. The outcome of these studies is an improved understanding of the effects that operational policies have on the behaviour of mixed hydro-thermal systems and, in particular, an improved knowledge of the response of the RTS. info:eu-repo/semantics/publishedVersion

The increasing trend in the consumption of various materials has also led to a huge increase in the final waste streams especially in the form of municipal solid waste (MSW) and the consequent environmental pollutions in particular greenhouse gas (GHG) emissions. These have made MSW management a significant environmental issue for governments and policy-makers. To address these challenges, developed countries have implemented sustainable material management (SMM) strategies which have been comprehensively reviewed herein. Moreover, waste generation statistics reported for most of the developed and developing countries as well as the existing gaps in MSW management among these countries have been fully discussed. The present paper was also aimed at comprehensively assessing electricity generation potentials from MSW using an integrated solid waste management system (including three different technologies of anaerobic digestion (AD), incineration, and pyrolysis-gasification) while the consequent GHG emission reduction potentials as a result of their implementation were also explored. To facilitate the understanding of the potential impacts of these treatment strategies, Iran's data were used as a case study. More specifically, the theoretical and technical potentials of electricity generation were calculated and the GHG emission reduction potentials were estimated using a life cycle assessment (LCA) approach. Overall, it was found that 5005.4–5545.8 GW h of electricity could be generated from MSW in Iran annually which could lead to approximately 3561–4844 thousand tons of avoided CO2eq. Such GHG reductions would be translated into approximately 0.5% of Iran's annual GHG emissions and would be considered a promising achievement given Iran's international GHGs reduction commitment, i.e., 4% reduction of anthropogenic GHGs emissions by 2030 below the business as usual scenario. Such findings could also be modeled for the other developing countries around the world where efficient MSW management is yet to be implemented.

Synthetic oxygen carriers based on geopolymer composites for chemical looping combustion have been recently proposed as alternative to traditional ones. In this work, this novel class of oxygen carriers was further developed by introducing manganese oxide (Mn2O3) as active phase. A geopolymer composite with Mn2O3 powder was produced and compared to a previously developed Fe-based system. Additionally, a mixed iron/manganese composite was fabricated to investigate possible combined effects of the two oxides. Laboratory experiments were carried out in a plant for the combustion of a CO rich gas from char gasification in CO2, consisting of two sequential fixed beds for char gasification and chemical looping combustion. The tests conducted at 900 °C pointed out the excellent performance of the Mn- and MnFe-based oxygen carriers, achieving an efficiency of CO conversion up to 99% during the first minute of operation with gas residence time less than 1 s. Moreover, the Mn-based materials exhibited the ability to release O2 during the initial stage of combustion. In the mixed iron/manganese system, the formation of the mixed phase MnFe2O4 was detected by XRD analysis, resulting in a beneficial synergistic effect. Both developed oxygen carriers (Mn- and MnFe based) exhibited similar CO conversion profiles after repeated cycles of operation.

This work presents the application of a new framework for sustainability metrics to industrial processes, in particular, to chemical processes. The sustainability of an industrial process can be evaluated using a set of three-dimensional (3D) indicators that represent all three dimensions of sustainability: economic, environmental, and societal. The four 3D metrics proposed in this worknamely, material intensity, energy intensity, potential chemical risk, and potential environmental impactare applicable to a wide range of process systems. The first two metrics are associated with the process operation. The remaining two metrics, potential chemical risk and potential environmental impact, respectively represent chemical risk to human health in the process environment, and the potential environmental impact of the process on the surrounding environment. To illustrate this framework and the applicability of the proposed set of 3D metrics, two case studies are presented: chlorine production process using th...

The aim of this work is to perform a feasibility study on the power line communication for the development of a new generation of interface devices (IDs) for smart grid applications. More in detail, this paper deals with one of the most important issues on this topic which is the communication system. Among the existing communication technologies, the study is focused on power line communications (PLCs). After a analysis of the state of the art in the field, the main aspects are analyzed, concerning the open issues on the use of PLCs, especially for medium voltage (MV) and low voltage (LV) systems. In this work the use of PLC in MV-LV networks is investigated, by means of simulations and experimental tests. These tests are performed in a test power network, which includes a MV overhead power line and a MV/LV transformer. The two ways communication channel is characterized, by transmitting a signal from the MV bus-bars and receiving it from the LV network and vice-versa. In this way the possibility to cross the power transformer is investigated

China contributes 23 % of global carbon emissions, of which 26 % originate from the household sector. Due to vast variations in both climatic conditions and the affordability and accessibility of fuels, household carbon emissions (HCEs) differ significantly across China. This study compares HCEs (per person) from urban and rural regions in northern China with their counterparts in southern China. Annual macroeconomic data for the study period 2005 to 2012 were obtained from Chinese government sources, whereas the direct HCEs for different types of fossil fuels were obtained using the IPCC reference approach, and indirect HCEs were calculated by input-output analysis. Results suggest that HCEs from urban areas are higher than those from rural areas. Regardless of the regions, there is a similarity in per person HCEs in urban areas, but the rural areas of northern China had significantly higher HCEs than those from southern China. The reasons for the similarity between urban areas and differences between rural areas and the percentage share of direct and indirect HCEs from different sources are discussed. Similarly, the reasons and solutions to why decarbonising policies are working in urban areas but not in rural areas are discussed.