Suchergebnisse

Teeth in Cervidae are permanent structures that are not replaceable or repairable; consequently their rate of wear, due to the grinding effect of food and dental attrition, affects their duration and can determine an animal's lifespan. Tooth wear is also a useful indicator of accumulative life energy investment in intake and mastication and their interactions with diet. Little is known regarding how natural and sexual selection operate on dental structures within a species in contrasting environments and how these relate to life history traits to explain differences in population rates of tooth wear and longevity. We hypothesised that populations under harsh environmental conditions should be selected for more hypsodont teeth while sexual selection may maintain similar sex differences within different populations. We investigated the patterns of tooth wear in males and females of Iberian red deer (Cervus elaphus hispanicus) in Southern Spain and Scottish red deer (C. e. scoticus) across Scotland, that occur in very different environments, using 10343 samples from legal hunting activities. We found higher rates of both incisor and molar wear in the Spanish compared to Scottish populations. However, Scottish red deer had larger incisors at emergence than Iberian red deer, whilst molars emerged at a similar size in both populations and sexes. Iberian and Scottish males had earlier tooth depletion than females, in support of a similar sexual selection process in both populations. However, whilst average lifespan for Iberian males was 4 years shorter than that for Iberian females and Scottish males, Scottish males only showed a reduction of 1 year in average lifespan with respect to Scottish females. More worn molars were associated with larger mandibles in both populations, suggesting that higher intake and/or greater investment in food comminution may have favoured increased body growth, before later loss of tooth efficiency due to severe wear. These results illustrate how independent selection in both subspecies, that diverged 11,700 years BP, has resulted in the evolution of different longevity, although sexual selection has maintained a similar pattern of relative sex differences in tooth depletion. This study opens interesting questions on optimal allocation in life history trade-offs and the independent evolution of allopatric populations. ; The European Union Lifelong Learning programme (Leonardo da Vinci) supported the post-graduate students that collaborated in this study. The Scottish Government through the Rural and Environment Science and Analytical Services Division (RESAS), Deer Commission Scotland and Scottish Natural Heritage (project RP64) and Spanish Ministry of Science (projects CGL2007-63594 and CGL2010-17163) funded this study. During the writing up of this study FJPB was granted with a visiting professor fellowship by the University of Cordoba (Spain).

Book of abastracts of the 15th International virtual conference on energy storage (Enerstock 2021), 9-11 June 2021, Ljubljana, Slovenia, pp. 267. ISBN 978-961-6104-49-4 ; INTRODUCTION: The main objective of the present study is to compare the 30-year life cycle assessment of two concentrating solar power systems with tower configuration, one without thermal energy storage and the other with thermal energy storage, in order to assess their potential impact on the environment. To achieve this aim, common reference characteristics have been defined in order to allow the optimal comparison. The reference power considered for both technologies has been 110 MW and the "power cycle" (turbine, alternator and generator) and the "cooling system" are the same in both configuration. In general terms, the significant differences between both configurations are focused on the area of the solar field, and with it the number of heliostats, and on the storage of thermal energy by inorganic salts. Although it is true that concentrating solar power plant (CSP) in tower without thermal energy storage is not a current commercial configuration, it is very interesting to be able to compare the environmental impacts of both configurations when thermal energy storage is added to the solar plant. In addition, the study ends by assessing whether the environmental impact that is generated by adding thermal energy storage compensates with the improvement of its manageability, its dispatchability and its contribution to decarbonisation. METHOD: Life cycle assessment (LCA) is a methodology that allows evaluating the environmental loads associated with a product, process or activity, identifying and quantifying the energy, the materials consumed and the waste released into the environment throughout the entire life cycle. The LCA included in this study is carried according to ISO 14040 and 14044. Thus, this LCA is based on the impact assessment method ReCiPe in impact points and GWP in kgCO2eq and the database used is Ecoivent 3.6, which has positioned itself as a world leader in creating more transparent life cycle impact databases. Moreover, this work encompasses three distinct phases of evaluation: manufacturing, operational, and end of life. RESULTS AND CONCLUSIONS: At the time of submitting this abstract, the study is on its way. ; This work was supported under the umbrella of CSP-ERA-Net 1st Cofund Joint Call by AEI - Spanish Ministry of Science, Innovation and Universities, TÜBITAK - Scientific and Technological Research Council of Turkey, and CSO - Israeli Ministry of Energy. CSP-ERA-Net is supported by the European Commission within the EU Framework Programme for Research and Innovation HORIZON 2020 (Cofund ERA-NET Action, N° 838311) and it was partially funded by Agencia Estatal de Investigación (AEI) - Ministerio de Ciencia, Innovación y Universidades (PCI2020-120695- 2/AEI/10.13039/501100011033), Ministerio de Ciencia, Innovación y Universidades de España (RTI2018-093849-B-C31 - MCIU/AEI/FEDER, UE), and Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (AEI) (RED2018- 102431-T). The authors would like to thank the Catalan Government for the quality accreditation given to their research group (2017 SGR 1537). GREiA is a certified agent TECNIO in the category of technology developers from the Government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme.

Thermal energy storage (TES) allows the existing mismatch between supply and demand in energy systems to be overcome. Considering temperatures above 150 C, there are major potential benefits for applications, such as process heat and electricity production, where TES coupled with concentrating solar power (CSP) plants can increase the penetration of renewable energies. To this end, this paper performs a critical analysis of the literature on the current and most promising concrete energy storage technologies, identifying five challenges that must be overcome for the successful exploitation of this technology. With these five challenges in mind, this paper proposes an approach that uses a new modular design of concrete-based TES. A preliminary study of the feasibility of the proposed system was performed using computational fluid dynamics (CFD) techniques, showing promising results. ; Funding: This work is part of PCI2020-120695-2 project funded by Ministerio de Ciencia e Innovación— Agencia Estatal de Investigación (MCIN/AEI/10.13039/501100011033) and by the European Union "NextGenerationEU/PRTR". This work was partially funded by the Ministerio de Ciencia, Innovación y Universidades de España (RTI2018-093849-B-C31—MCIU/AEI/FEDER, UE) and by the Ministerio de Ciencia, Innovación y Universidades—Agencia Estatal de Investigación (AEI) (RED2018-102431-T). Acknowledgments: The authors at University of Lleida would like to thank the Catalan government for quality accreditation (2017 SGR 1537). GREiA is a certified TECNIO agent in the category of technology developers from the government of Catalonia. This work is partially supported by ICREA under the ICREA Academia programme.

Existing commercial parabolic trough power plants use thermal oil as a heat transfer fluid, with working temperatures in the region of 400 °C. In order to achieve more efficient generating systems, a second generation of parabolic troughs that operate at temperatures higher than 400 °C is being developed. One possibility Abengoa Solar is assessing is the use of direct steam generation (DSG) inside parabolic troughs in order to achieve higher temperatures; in a first stage heating up to 450 °C and in a second stage heating up to 550 °C. For the future market potential of parabolic trough power plants with DSG, it is beneficial to integrate thermal energy storage (TES) systems. Different TES options based on the most known technologies, steam accumulators, molten salts (MS), and phase change materials (PCM), are presented and compared in this paper. This comparison shows as main conclusion of the study that a combined system based on PCM-MS has a clear advantage in the ratio with 6 or more equivalent hours of storage, while with lower than 6 h, steam accumulators are considered the best option. ; The work partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER)). Prof. Luisa F. Cabeza would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123). This project has received funding from the European Commission Seventh Framework Programme (FP/2007-2013) under Grant agreement N°PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 657466 (INPATH-TES).

This paper presents the importance of the thermal losses in the performance evaluation of thermal storage systems. In order to reinforce this statement, an evaluation of a pilot plant whose size is sufficiently representative for the extrapolation of results at larger scales has been carried out. The evaluation of the heat losses of a molten salt pilot plant with 8.1 MWhth built in Spain by Abengoa is presented. While the storage materials development has attracted a lot of attention from the researchers, the performance of a two-tank storage system has not been evaluated in detail. The relevance of the design of conventional systems such as insulation, mechanical assembly or foundation, are found to be the key for the feasibility of a TES system. Different performance scenarios were performed and based on experimental results, decisions for reengineering of the pilot plant could be taken to improve commercial storage plants. ; The research leading to these results has received funding from Spanish goverment (Fondo tecnológicoIDI-20090393, ConSOLida CENIT 2008-1005). The work is partially funded by the Spanish government (ENE2011-28269-C03-02, ENE2011-22722). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREA (2014 SGR 123) and research group DIOPMA (2014 SGR 1543).

To be able to extend the operation of a solar power plant (CSP) up to 15 h, thermal energy storage (TES) is necessary. But TES also provides more versatility to the plant and makes its reliance during operation hours more dependable. On the other hand, due to the different CSP configurations, a broad spectrum of storage technologies, materials and methods is needed. Sensible and latent heat storage are known technologies in CSP, but thermochemical storage (TCS) is still very much at laboratory level. Nevertheless, TCS has de advantage of nearly no losses during storage and very good volumetric energy density. This review summarizes and compares the different TCS that are today being investigated. Those systems are based in three redox reactions, sulfur-based cycles, metal oxide reduction–oxidation cycles, and perovskite-type hydrogen production, and metal oxide non-redox cycles due to their similarity. This review shows that all these cycles are promising, but none of them seems to have all the characteristics necessary to become the only one storage system for CSP. The main conclusion of the review is that the calcium carbonate is the cycle with most experimentation behind it to infer that it could be viable and should thus be attempted at a research plant scale once a reactivation cycle can be designed; and the manganese oxide cycle, while less developed, is fundamental enough to be a suitable application for desert climates over the rest of the water-frugal or even water-avoiding cycles. ; The work was partially funded by the Spanish government (project ENE2011−22722). The authors would also like to thank the Catalan Government for the quality accreditation given to their research group GREA (2014 SGR 123) and DIOPMA (2014 SGR 1543). The research leading to these results has received funding from the European Union׳s Seventh Framework Programme (FP7/2007−2013) under Grant agreement n° PIRSES-GA−2013−610692 (INNOSTORAGE).