10 research outputs found

    Exploring the roles of storage technologies in the Spanish electricity system with high share of renewable energy

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    At operational level, fossil fuel phase-out and high shares of non-dispatchable renewable energy resources (RES) will challenge the system operator's (SO) ability to balance generation, and the demand at any time. The variability of RES output ranges from one hour to a season, and critical events such as low supply and high demand might occur more frequently and for more extended periods. When evaluating the role of Energy Storage Systems (ESSs) in this context, the need for a long time scope to capture the different RES variabilities must be reconciled with the need for modeling the hourly chronology. This paper presents a medium-term operation planning model, addressing both the energy dispatch and the balancing services. This study shows that representing the combined chronological variability of demand and RES production is essential to properly assess the roles of different kinds of ESSs in the future 2030 electricity mix. Otherwise, it would not be possible to appropriately capture the frequency, depth, and length of events for which ESSs are activated. The analysis also highlights the importance of considering balancing services, given the significant contribution of batteries to the reserve market. Finally, the results show that batteries and Pumped Storage Hydro (PSH) have different roles in the Spanish electricity system with a high renewable penetration. While PSH is mainly used to provide energy during critical periods, batteries mostly provide balancing services. © 2022 The Author(s)This research has been carried out thanks to the Spanish Ministry of Economy and Competitiveness MINECO through BC3 Mar?a de Maeztu excellence accreditation MDM-2017-0714 Maria de Maeztu Grant. The research has also benefited from the funding of the RETOS COLABORACI?N program of the Spanish Ministry of Science and Innovation and the Spanish State Research Agency (project ?Platform of innovative models to accelerate the energy decarbonization of the economy (MODESC)?, with reference number RTC2019- 007315-3). The authors would also like to acknowledge the Iberdrola Chair of Energy and Innovation for their helpful comments

    Storage and demand response contribution to firm capacity: Analysis of the Spanish electricity system

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    Provision of firm capacity will become a challenge in power systems dominated by renewable generation. This paper analyzes the competitiveness and role of battery storage, six types of pumped-hydro storage, open cycle gas turbine (OCGT), and demand response (DR) technologies in providing the firm capacity required to guarantee the security of supply in a real-size power system such as the Spanish one in horizon 2030. The paper contributes with detailed and realistic modeling of the DR capabilities. Demand is disaggregated by sector and activities and projected towards 2030, applying a growth rate by activity. The load flexibility constraints are considered to ensure the validity of the results. A generation operation planning and expansion model, SPLODER, is conveniently upgraded to properly represent the different storage alternatives addressed in the paper. The results highlight the importance of considering demand response for evaluating long-term firm capacity requirements, showing a non-negligible impact on the investment decisions on the amount of firm capacity required in the system and the optimal shares of wind and solar PV renewable generation. Results also show the dominance of cost-competitiveness of pumped hydro and OCGTs over batteries. Additionally, capacity payments are required to support firm capacity providers’ investments. © 2022This research has been carried out thanks to the Iberdrola Chair on Energy and Innovation and the funding of the RETOS COLABORACIÓN program of the Spanish Ministry of Science and Innovation and the Spanish State Research Agency (project “Platform of innovative models to accelerate the energy decarbonization of the economy (MODESC)”, with reference number RTC2019-007315-3 ). This research is also supported by the Spanish Ministry of Economy and Competitiveness MINECO through BC3 MarĂ­a de Maeztu excellence accreditation MDM-2017-0714

    TendĂȘncias do diabetes mellitus no Brasil: o papel da transição nutricional Trends in diabetes mellitus in Brazil: the role of the nutritional transition

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    A prevalĂȘncia do diabetes mellitus tipo 2 tem se elevado vertiginosamente e espera-se ainda um maior incremento. Na AmĂ©rica Latina hĂĄ uma tendĂȘncia do aumento da freqĂŒĂȘncia entre as faixas etĂĄrias mais jovens, cujo impacto negativo sobre a qualidade de vida e a carga da doença ao sistema de saĂșde Ă© relevante. O aumento das taxas de sobrepeso e obesidade associado Ă s alteraçÔes do estilo de vida e ao envelhecimento populacional, sĂŁo os principais fatores que explicam o crescimento da prevalĂȘncia do diabetes tipo 2. As modificaçÔes no consumo alimentar da população brasileira - baixa freqĂŒĂȘncia de alimentos ricos em fibras, aumento da proporção de gorduras saturadas e açĂșcares da dieta - associadas a um estilo de vida sedentĂĄrio compĂ”em um dos principais fatores etiolĂłgicos da obesidade, diabetes tipo 2 e outras doenças crĂŽnicas. Programas de prevenção primĂĄria do diabetes vĂȘm sendo desenvolvidos em diversos paĂ­ses, cujos resultados demonstram um impacto positivo sobre a qualidade de vida da população.<br>Prevalence of type 2 diabetes mellitus has increased rapidly and is expected to increase even further. In Latin America countries there is an upward trend among the younger age groups, with a major negative impact on the quality of life and burden of the disease for the health care system. Increasing rates of overweight and obesity associated with lifestyle changes and aging of the population are the main contributing factors to the increasing prevalence of type 2 diabetes. Dietary shifts in the Brazilian population (low frequency of fiber-rich foods and heavy consumption of saturated fatty acids and sugars) and sedentary lifestyle are the main risk factors for obesity, type 2 diabetes, and other chronic diseases. Diabetes prevention programs are being promoted in several countries with results showing improvement in quality of life

    Differences in clinical manifestations and increased severity of systemic lupus erythematosus between two groups of Hispanics: European Caucasians versus Latin American mestizos (data from the RELESSER registry).

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    Systemic lupus erythematosus (SLE) is regarded as a prototype autoimmune disease because it can serve as a means for studying differences between ethnic minorities and sex. Traditionally, all Hispanics have been bracketed within the same ethnic group, but there are differences between Hispanics from Spain and those from Latin America, not to mention other Spanish-speaking populations. This study aimed to determine the demographic and clinical characteristics, severity, activity, damage, mortality and co-morbidity of SLE in Hispanics belonging to the two ethnic groups resident in Spain, and to identify any differences. This was an observational, multi-centre, retrospective study. The demographic and clinical variables of patients with SLE from 45 rheumatology units were collected. The study was conducted in accordance with Good Clinical Practice guidelines. Hispanic patients from the registry were divided into two groups: Spaniards or European Caucasians (EC) and Latin American mestizos (LAM). Comparative univariate and multivariate statistical analyses were carried out. A total of 3490 SLE patients were included, 90% of whom were female; 3305 (92%) EC and 185 (5%) LAM. LAM patients experienced their first lupus symptoms four years earlier than EC patients and were diagnosed and included in the registry younger, and their SLE was of a shorter duration. The time in months from the first SLE symptoms to diagnosis was longer in EC patients, as were the follow-up periods. LAM patients exhibited higher prevalence rates of myositis, haemolytic anaemia and nephritis, but there were no differences in histological type or serositis. Anti-Sm, anti-Ro and anti-RNP antibodies were more frequently found in LAM patients. LAM patients also had higher levels of disease activity, severity and hospital admissions. However, there were no differences in damage index, mortality or co-morbidity index. In the multivariate analysis, after adjusting for confounders, in several models the odds ratio (95% confidence interval) for a Katz severity index >3 in LAM patients was 1.45 (1.038-2.026; p = 0.02). This difference did not extend to activity levels (i.e. SLEDAI >3; 0.98 (0.30-1.66)). SLE in Hispanic EC patients showed clinical differences compared to Hispanic LAM patients. The latter more frequently suffered nephritis and higher severity indices. This study shows that where lupus is concerned, not all Hispanics are equal

    Molecular Dynamics Simulations Shed Light on the Enthalpic and Entropic Driving Forces That Govern the Sequence Specific Recognition between Netropsin and DNA

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    CTA Contributions to the 34th International Cosmic Ray Conference (ICRC2015)

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    List of contributions from the CTA Consortium presented at the 34th International Cosmic Ray Conference, 30 July - 6 August 2015, The Hague, The Netherlands.Comment: Index of CTA conference proceedings at the ICRC2015, The Hague (The Netherlands). v1: placeholder with no arXiv links yet, to be replaced once individual contributions have been all submitted; v2: final with arXiv links to all CTA contributions and full author lis
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