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CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia Solar RESUMEN: Un composite constituido del eutéctico binario ácido cáprico/ácido mirístico (CA:MA) y un soporte mineral poroso colombiano fue desarrollado para aplicaciones de almacenamiento de energía térmica alrededor de los 26 °C. Diferentes porcentajes de impregnación de CA:MA (25%, 35% y 40%) en el soporte fueron estudiados para determinar los valores óptimos en términos de filtración. El mejor composite obtenido, con el 35% de CA:MA y menos del 1,5% de filtración, fue caracterizado térmicamente mediante calorimetría diferencial de barrido (DSC), así mismo, se evaluaron su conductividad térmica, capacidad calorífica y estabilidad térmica a través de las técnicas del hilo caliente, calorimetría diferencial de barrido modulada (MDSC) y ciclado térmico, respectivamente. ABSTRACT: A composite consisting of the binary eutectic capric acid/myristic acid (CA:MA) and a Colombian porous mineral support was developed for thermal energy storage applications around 26 °C. Different percentages of CA:MA impregnation (25%, 35% and 40%) in the support were studied to determine the optimal values in terms of leakage. The best composite obtained, with 35% CA:MA and less than 1.5% of leakage, was thermally characterized by differential scanning calorimetry (DSC). Besides, its thermal conductivity, heat capacity and thermal stability were evaluated through the techniques of hot wire, modulated differential scanning calorimetry (MDSC) and thermal cycling, respectively. info:eu-repo/semantics/publishedVersion

The use of thermal energy storage by phase change materials (PCM) is increasing in interest for building applications. For the deployment of the technology, appropriate characterization of PCM and hybrid PCM is essential, but it is not always possible to carry it out with conventional equipment, mainly due to the sample size. This paper shows equipment developed in different research centers and universities to analyze thermophysical properties, such as specific heat, latent heat and melting temperature, and thermal conductivity and diffusivity of PCM and hybrid PCM materials. © 2014 Elsevier Ltd. ENE2011-28269-C03-01, ENE2011-22722, ENE2011-28269-C03-02 European Commission 110M032 Qatar Foundation: BES-2012–051861 COST TU0802 The work is partially funded by the European Union (COST Action COST TU0802 ), the Spanish government ( ENE2011-28269-C03-01 , ENE2011-28269-C03-02 and ENE2011-22722 ), TUBITAK (project 110M032 ), and by Qatar National Foundation through the NPRP No.: 4–465-2–173 . The authors would like to thank the Catalan Government for the quality accreditation given to the research group GREA ( 2014 SGR 123 ) and their research group DIOPMA (2014 SGR 1543), both in Spain. Laia Miró would like to thank the Spanish Government for her research fellowship ( BES-2012–051861 ).

Due to the high interest of appropriate characterization of PCM and hybrid PCM composites, different research centres and universities are using several material characterization techniques not commonly used with PCM, to study the structure and morphology of these materials. Likewise, physico-chemical stability is a crucial parameter for the performance of latent storage materials during time and its evaluation has been done by using molecular spectroscopy, chemiluminiscence or calorimetric tests. Atomic force microscopy and nanoindentation are also reported to characterize hybrid PCM composites. Other chemical aspects studied are related with the compatibility of the PCM and its container and also considered in this compilation of characterization work.

The use of thermal energy storage by phase change materials (PCM) is increasing in interest for building applications. For the deployment of the technology, appropriate characterization of PCM and hybrid PCM is essential, but it is not always possible to carry it out with conventional equipment, mainly due to the sample size. This paper shows equipment developed in different research centers and universities to analyze thermophysical properties, such as specific heat, latent heat and melting temperature, and thermal conductivity and diffusivity of PCM and hybrid PCM materials.

At this moment, the global energy consumption in buildings is around 40% of the total energy consumption in developed countries. Thermal energy storage (TES) is presented as one way to address this energy-related problem proposing an alternative to reduce the gap between energy supply and energy demand. One way to store energy is using thermochemical materials (TCM). These types of materials allow accumulating energy through a chemical process at low temperature, almost without heat losses. In addition, it is a stable way to perform the heat storage and TCM can be implemented for seasonal storage or/and long term storage. This study compares the cyclability, from the thermophysical point of view, CaCl2 which follows a chemical reaction and zeolite which follows a sorption process to be used as TCM for seasonal/long term storage. The main results show that the chemical reaction TCM is more energy-efficient than the sorption TCM. The CaCl2 calculated energy density is 1.47GJ/m3, being the best option to be considered to be used as TCM, even though the dehydration process of the zeolite is simpler and it occurs at higher temperatures its calculated energy density is only 0.2GJ/m3.

This chapter aims to update the knowledge on the building sector since the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) from a mitigation perspective. Buildings and activities in buildings are responsible for a significant share of GHG emissions, but they are also the key to mitigation strategies. In 2010, the building sector accounted for approximately 117 Exajoules (EJ) or 32% of global final energy consumption and 19% of energy-related CO2 emissions; and 51% of global electricity consumption. Buildings contribute to a significant amount of F-gas emissions, with large differences in reported figures due to differing accounting conventions, ranging from around an eighth to a third of all such emissions. The chapter argues that beyond a large emission role, mitigation opportunities in this sector are also significant, often very cost-effective, and are in many times associated with significant co-benefits that can exceed the direct benefits by orders of magnitude. The sector has significant mitigation potentials at low or even negative costs. Nevertheless, without strong actions emissions are likely to grow considerably - and they may even double by mid-century - due to several drivers. The chapter points out that certain policies have proven to be very effective and several new ones are emerging. As a result, building energy use trends have been reversed to stagnation or even reduction in some jurisdictions in recent years, despite the increases in affluence and population. The chapter uses a novel conceptual framework, in line with the general analytical framework of the contribution of Working Group III (WGIII) to the IPCC Fifth Assessment Report (AR5), which focuses on identities as an organizing principle.

10.1016/j.solener.2013.07.023 In the buildings sector, the use of ventilated double skin facades in order to reduce the energy demand and the environmental impact of the building during its operational phase has grown significantly. However, the use of this constructive system could lead to high environmental costs during the manufacturing and dismantling phase of the building. This paper presents a life cycle assessment (LCA) study based on the EcoIndicator 99 of a ventilated facade with PCM in its air chamber. Two cubicles were built in an experimental set-up located in Puigverd de Lleida (Spain), one with this ventilated facade system and the other without. The differences in the electrical energy consumption of the HVAC systems were registered and used to determine the environmental savings produced during the operational phase of each building. The results of the LCA show that considering a lifetime of 50 years, the use of this particular ventilated facade reduces by 7.7% the overall environmental impact of the whole building. It also highlights that the environmental payback of this active system is significantly lower than other systems which use PCM in the building envelopes. The environmental payback of the system is 30 years, which can be reduced to only 6 years if instead steel wood would have been used in the structure.