Search

In Latin America the renewable energy has increased in 40GW, during the last twenty years; in this perspective countries as Perú, Chile, Brazil, Bolivia and Colombia have extensive desert with the highest irradiance and large field available for this technology. One example is the Atacama Desert and its extension in Chile and Peru; however, it has some challenges as the water availability. Therefore, the clean water availability for industry and agriculture is a problem, only 2.5% of the world’s water is fresh water, this value is decreasing every year for agriculture and industrial process. Our methodology has been applied during 2019 to 2021 with a real case study, one water machine has generated 128,000 L of water per year, >230% of efficiency compared with traditional techniques with the same energy consumption: its contribution with a correlational study of 92.33%. The purpose of this study is to introduce and evaluate the performance of a new clean water production from the sun and atmospheric humidity. Revisión por pares

In this work, the management of photovoltaic (PV) energy, assisted by a redox flow battery (RFB), for powering an electrochemical advanced oxidation process (EAOP), is evaluated. The storage of surplus energy allows to extend the treatment time overnight and to increase the environmental remediation efficiency during the whole electrochemical treatment. Nevertheless, this work points out that it is important to evaluate the most suitable powering strategy to take advantage of the total solar energy produced. The energy supplied by the PV panels to each system depends on the electrical features of the electrochemical devices (electrooxidation reactor and the RFB) and, especially, on the connection between them (series or parallel). A straightforward coupling (without a targeted regulation of the energy distributed between the EAOP and the RFB) brings out a time-depending and uncontrolled powering. This type of strategy opposes to the smarter regulation of the energy between the EAOP and the RFB by means of a targeted powering to each device. Results show higher remediation degrees when both electrochemical devices are directly coupled in parallel, regardless of the operational mode used (straightforward or targeted) due to lower current densities lead to higher global performances for both electrochemical devices. Nonetheless, it is important to note that the green targeted powering notices higher remediations than the straightforward coupling when the system operates under parallel connection and a RFB control. The low current densities supplied to the RFB point out higher capacities and, consequently, the remediation treatment is extended. Those results shed light on interesting conclusions in terms of green energy use. Furthermore, this software tool allows by means of a simple predictive modelling to optime the operational conditions of electrochemical treatments powered by renewable energies and assisted by energy storage systems.

[EN] This paper proposes the use of principal component analysis (PCA) for the state of health (SOH) diagnosis of a battery energy storage system (BESS) that is operating in a renewable energy laboratory located in Chocó, Colombia. The presented methodology allows the detection of false alarms during the operation of the BESS. The principal component analysis model is applied to a parameter set associated to the capacity, internal resistance and open circuit voltage of a battery energy storage system. The parameters are identified from experimental data collected daily. The PCA model retains the first 5 components that collect 80.25% of the total variability. During the test under real operation contidions, PCA diagnosed a degradation of state of health fastest than the comercial battery controller. A change in the charging modes lead to a battery recovery that was also monitored by the proposed algortihm, and control actions are proposed that lead the BESS to work in normal conditions., The authors would like to acknowledge the research project "Implementacion de un programa de desarrollo e investigacion de energias renovables en el departamento del Choco, BPIN 2013000100285 (in Spanish)" and the Universidad TecnolOgica del Choco (in Spanish). The authors would like to thank the anonymous reviewers as well as the editor for their valuable comments that have greatly improved the final version of the paper.

The development of newer and more ecofriendly energies is now more important in the world. Solar energy has been growing considerably over the last years, and, for example, photovoltaic solar farms size has increased, where the problems in operation and maintenance also has raised. Automated inspection is being applied with emerging hardware and software technologies such as computer vision, unmanned aerial vehicles and thermal cameras. This chapter illustrates an integration of all these technologies, coming up with an effective solution for the detection of malfunctioning solar panels in large solar parks Ministerio de Economía y Competitividad (RTC-2016-5694-3) No data (2018) UEM

Highlighted experimental studies on nanofluids reveal an anomalous increment in the specific heat capacity (Cp) of these ionic systems when nanoparticles are added. This fact is really important due the applicability of nanofluids in concentrating solar power plants as heat transfer fluid and storage media. These are promising results for the development of high-temperature heat storage applications by enhanced storage capacity materials. The present work focuses on the study of this effect in NaNO3 molten salt doped with SiO2 nanoparticles by molecular dynamics (MD) simulations and Differential Scanning Calorimetry (DSC) experiments. The study shows that for nanoparticles’ concentrations around 1% wt. the Cp increases by 26% compared to pure NaNO3, whereas at higher concentrations the effect disappears. The results approach high agreement between experimental and simulation results and MD simulations reveal that the increase of Cp at low concentrations is explained by the formation of a semi ordered layer of ionic fluid. This layer is rich in Na+ cations, around the nanoparticles whereas the reduction of Cp at concentrations higher than 2% wt. is related to the aggregation of nanoparticles as revealed by Scanning Electron Microscopy (SEM). However, deep experimental results with other materials will be required in order to validate the layering effect.

Co-adsorbing molecules attain certain control in the surrounding of the dyes leading to enhanced efficiencies mainly by affecting the recombination of the photogenerated electrons and aggregation of dyes. Bile acids such as deoxycholic acid (DOA) and chenodeoxycholic acid (CDOA) yield competitive photovoltaic parameters. We harness the steroid backbone of bile acids to chemically modified it at its R3 position attaching sterically demanding amide groups rather than typically terminal hydroxyl groups (3β-position) as in DOA and CDOA. All possible resultant effects on the performance in complete DSSCs were studied by current density-voltage curves (e.g., percentage of efficiency, %η; open-circuit voltage, Voc; short-circuit photocurrent, Jsc; and fill factor, FF), incident photon-to-current conversion efficiency (IPCE), and a set of interfacial data by electrochemical impedance spectroscopy (EIS). Our co-adsorbates stand out by enhancing the conversion efficiencies, being in some cases competitive with photovoltaic parameters of DOA and CDOA. Universidad de Costa Rica/[804-B2-A01]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Electroquímica y Energía Química (CELEQ) UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Química

Electrocoagulation (EC) of wastewater polluted with 100 mg dm−3 of oxyfluorfen (OFF) has been studied in cells with iron anodes and aluminum cathodes. Solar power combined with energy storage in a vanadium redox flow battery (VRFB) has been used to electrically power a continuous EC process. Three scenarios have been evaluated. Firstly, a constant current was applied to the EC reactor. Secondly, a solar energy profile was applied to the EC reactor and the RFB. Finally, the EC process was operated in the same way as the second scenario except that the RFB was powered with double the current charge than in the second scenario. The results show that electrocoagulation is not suitable for the complete removal of oxyfluorfen from wastewater, although it attained a significant pollutant accumulation into the flocs of 25%, showing potential as a pretreatment for this kind of waste. Likewise, results obtained pointed out that electrocoagulation can be powered directly with solar energy and this energy can also be regulated by VRFB, although, in the latter case, to attain the same treatment efficiency, around 1/3 more energy is required during energy storage. In addition, the higher the energy provided by the VRFB is, the lower the Fe/Al ratio produced during the electrocoagulation is.

23 pages, 6 figures, 5 tables, 6 appendices, The transition to renewable energies will intensify the global competition for land. Nevertheless, most analyses to date have concluded that land will not pose significant constraints on this transition. Here, we estimate the land-use requirements to supply all currently consumed electricity and final energy with domestic solar energy for 40 countries considering two key issues that are usually not taken into account: (1) the need to cope with the variability of the solar resource, and (2) the real land occupation of solar technologies. We focus on solar since it has the highest power density and biophysical potential among renewables. The exercise performed shows that for many advanced capitalist economies the land requirements to cover their current electricity consumption would be substantial, the situation being especially challenging for those located in northern latitudes with high population densities and high electricity consumption per capita. Assessing the implications in terms of land availability (i.e., land not already used for human activities), the list of vulnerable countries enlarges substantially (the EU-27 requiring around 50% of its available land), few advanced capitalist economies requiring low shares of the estimated available land. Replication of the exercise to explore the land-use requirements associated with a transition to a 100% solar powered economy indicates this transition may be physically unfeasible for countries such as Japan and most of the EU-27 member states. Their vulnerability is aggravated when accounting for the electricity and final energy footprint, i.e., the net embodied energy in international trade. If current dynamics continue, emerging countries such as India might reach a similar situation in the future. Overall, our results indicate that the transition to renewable energies maintaining the current levels of energy consumption has the potential to create new vulnerabilities and/or reinforce existing ones in terms of energy and food security and biodiversity conservation, This work has been partially developed under the MEDEAS project, funded by the European Union's Horizon 2020 Research and Innovation Programme under Grant agreement no. 691287

The chapter introduces the fundamentals of solar pond technology as a thermal storage process. It includes a brief description of solar pond technology in the context of energy storage, history, fundamentals; a classification of the different ponds used for capture and storage of solar energy; the fundamentals of the salinity gradient solar pond, describing the research efforts over recent decades; the design, construction, and the establishment of the salinity gradient, operation, and control; and finally the heat extraction systems. A discussion of investment, construction, and operational cost is also presented together with a review of the different applications in which solar ponds have the potential to supply low-grade thermal energy.

This article aims to contribute to the debate on energy transitions in Europe, by focusing on community perceptions in a southern European country marked by a significant development of renewable energy in recent years, Portugal. Three main dimensions of community perceptions of the impact, both positive and negative, of renewables are addressed: environmental, landscape and socioeconomic. The article is based on case studies of communities living in the vicinities of three wind farms and a solar power plant. The results show that not only community perceptions are heterogeneous but also that, in order to better understand the factors for social acceptance, it is crucial to examine perceptions not just at the planning stage but also once the energy infrastructures are constructed and functioning.

Thermal energy storage (TES) is recognised as a key technology for further deployment of renewable energy and to increase energy efficiency in our systems. Several technology roadmaps include this technology in their portfolio to achieve such objectives. In this paper, a first attempt to collect, organise and classify key performance indicators (KPI) used for TES is presented. Up to now, only KPI for TES in solar power plants (CSP) and in buildings can be found. The listed KPI are quantified in the literature and compared in this paper. This paper shows that TES can only be implemented by policy makers if more KPI are identified for more applications. Moreover, close monitoring of the achievements of the already identified KPI needs to be carried out to demonstrate the potential of TES. 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). 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).

Concentrated solar energy gives controlled high flux density with a wide wavelength spectrum by means of solar furnaces, which design allows to attain very high heating rates and very high temperatures up to 3500 K. Solar furnaces are specially suitable for transformation or synthesis process, these installations are devoted to research in the fields of material characterization and treatment as well as chemical processes. During 2001, several test campaigns have been carried out in the Solar Furnace at the Plataforma Solar de Almería in collaboration with different European research institutes, under the umbrella of the European Commission`s Improving Human Potential Programme. Thus different lines of work have been launched demonstrating the feasibility and potential use of solar furnaces for such R&D field.La energía solar concentrada permite proporcionar de forma controlada altas densidades de flujo energético con un amplio espectro de longitudes de onda mediante el uso de hornos solares, cuyo diseño permite alcanzar velocidades de calentamiento muy altas y temperaturas de hasta 3500ºC. Los hornos solares, por sus características, son especialmente adecuados para aplicaciones que conlleven la transformación o síntesis de materiales, siendo instalaciones dedicadas a la investigación en los campos de tratamiento y caracterización de materiales y procesos químicos. Durante el año 2001 en el Horno Solar de la Plataforma Solar de Almería se han realizado varias campañas de ensayos en colaboración con distintos centros de investigación europeos dentro del programa IHP de la Comisión Europea, abordándose diversas líneas de trabajo que han vuelto a demostrar la viabilidad y potencialidad del uso de los hornos solares para el tratamiento de materiales.

During the last 25 years, the author has designed, constructed, studied and promoted solar oven, hybrid solar/electric oven, solar oven cum drier, solar cooker cum water heater and solar still. In different parts of the world, solar cookers have been made, studied, patented, however, their real uses are very limited due to many reasons—unstable climate, economic, cultural, social and single use, etc. In order to overcome part of the problems mainly the last one, author has recently designed one hybrid food processor (multi-purposes device) and studied various technical and practical aspects. It has been used for cooking, heating/pasteurizing water (to inactivate microbes) and distillation of small quantity of water (to remove different minerals) and drying domestic products (fruits, vegetables and condiments/herbs, etc.). For more than three years of use, author has found this to be a useful device, mainly from convenience, fuel saving, economic and also from ecological point of view. This device can be used at any time and for different uses but with the reduced consumption of conventional fuel. r 2006 Elsevier Ltd. All rights reserved Durante los últimos 25 años, el autor ha diseñado, construido, estudiado y promovido horno solar, horno híbrido solar/eléctrico, horno solar con secador, cocina solar con calentador de agua y destilador solar. En diferentes partes del mundo se han fabricado, estudiado, patentado cocinas solares, sin embargo, sus usos reales son muy limitados por muchas razones: clima inestable, económico, cultural, social y de un solo uso, etc. los problemas principalmente el último, el autor ha diseñado recientemente un procesador de alimentos híbrido (dispositivo multipropósito) y ha estudiado varios aspectos técnicos y prácticos. Se ha utilizado para cocinar, calentar/pasteurizar agua (para inactivar microbios) y destilar pequeñas cantidades de agua (para eliminar diferentes minerales) y secar productos domésticos (frutas, verduras y condimentos/hierbas, etc.). Durante más de tres años de uso, el autor ha encontrado que este es un dispositivo útil, principalmente desde el punto de vista de conveniencia, ahorro de combustible, económico y también ecológico. Este dispositivo se puede utilizar en cualquier momento y para diferentes usos pero con el consumo reducido del combustible convencional. 2006 Elsevier Ltd. Todos los derechos reservados Universidad Nacional, Costa Rica Departamento de Física

Two folding and light solar ovens designed and constructed by Solar Box Cookers International (SBCI), Sacramento, U.S.A., have been studied experimentally. Furthermore, their performance is com pared with standard two glass solar ovens designed by one of us (S.S.N.), in the climate of Costa Rica. According to our measurements, made with and without load, taken during 30 different days, both cardboard ovens are 15-25% less efficient than the conventional oven and, secondly, the improved SBCI oven is slightly better than the previous SBCI oven. Se han estudiado experimentalmente dos hornos solares plegables y ligeros diseñados y construidos por Solar Box Cookers International (SBCI), Sacramento, EE.UU. Además, se compara su desempeño con dos hornos solares estándar de vidrio diseñados por uno de nosotros (S.S.N.), en el clima de Costa Rica. Según nuestras mediciones, realizadas con y sin carga, tomadas durante 30 días diferentes, ambos hornos de cartón son un 15-25% menos eficientes que el horno convencional y, en segundo lugar, el horno SBCI mejorado es ligeramente mejor que el horno SBCI anterior. Universidad Nacional, Costa Rica Departamento de Física

Inexpensive and easy to fabricate solar ovens have been made with available materials. One reflector has also been mounted to increase the input radiation on the hot absorbing plate which can be adjusted manually according to the need. This has been used by the author for the last 7 years to cook almost all types of vegetables, including rice, pulses, chicken, fish and beef and to bake bread and cake etc. Experimental studies have also been made on the variation of plate temperature, solar intensity, time to cook vegetables. These are given for the various cases of adjustment of the oven, depending on the convenience for the user. Furthermore, the insulating properties of the cooker are also studied. Maximum plate temperature observed was between 130 and 150°C and one cooked meal for a family of four persons can be made in 2–3 h. Thermal efficiency and heat loss coefficient, deduced from these measurements, varies between 30–40% and 4–9 W/m2°C. Simple theoretical analyses have beend used to explain these experimental data, taking into account heat capacity of various materials. The agreement is fairly good. Finally, some practical conclusions have been drawn. Se han fabricado hornos solares económicos y fáciles de fabricar con los materiales disponibles. También se ha montado un reflector para aumentar la radiación de entrada en la placa absorbente caliente que se puede ajustar manualmente según la necesidad. Este ha sido utilizado por el autor durante los últimos 7 años para cocinar casi todo tipo de verduras, incluyendo arroz, legumbres, pollo, pescado y ternera y para hornear pan y pasteles, etc. También se han realizado estudios experimentales sobre la variación de la temperatura de la placa , intensidad solar, tiempo de cocción de las verduras. Estos se dan para los distintos casos de ajuste del horno, según la conveniencia del usuario. Además, también se estudian las propiedades aislantes de la cocina. La temperatura máxima del plato observada estuvo entre 130 y 150 °C y se puede preparar una comida cocinada para una familia de cuatro personas en 2 a 3 h. La eficiencia térmica y el coeficiente de pérdida de calor, deducidos de estas mediciones, varían entre 30-40% y 4-9 W/m2°C. Se han utilizado análisis teóricos simples para explicar estos datos experimentales, teniendo en cuenta la capacidad calorífica de varios materiales. El acuerdo es bastante bueno. Finalmente, se han extraído algunas conclusiones prácticas. Universidad Nacional, Costa Rica Departamento de Física

We investigate solar combined heat and power (S-CHP) systems based on hybrid photovoltaic-thermal (PVT) collectors for the simultaneous provision of domestic hot water (DHW), space heating (SH) and power to single-family homes. The systems include PVT collectors with a polycarbonate flat-box structure design, a water storage tank, an auxiliary heater and a battery storage subsystem. A methodology is developed for modelling the energetic and economic performance of such PVT-based S-CHP systems, which is used to optimally size and operate systems for covering the energy demands of single-family reference households at three selected locations: Athens (Greece), London (UK) and Zaragoza (Spain). The results show that optimised systems are capable of covering ∼65% of the annual household electricity demands in Athens, London and Zaragoza when employing 14.0, 17.0 and 12.4 m2 collector array areas respectively, while also covering a significant fraction of the thermal energy demands in Athens (∼60%) and Zaragoza (∼45%); even in London, almost 30% of the reference household’s thermal demand is covered by such a system. A corresponding economic analysis reveals that, despite the suitability of Athens’ weather conditions for implementing such solar-energy systems, the payback time (PBT) of the optimised S-CHP system in Athens is 15.6 years in contrast to the 11.6 years predicted for Zaragoza, due to the lower electricity prices in Greece. On the other hand, the high carbon emission factor of the electricity grid in Greece makes these systems particularly promising at this location. Specifically, the investigated systems have the potential to displace 3.87, 1.65 and 1.54 tons of CO2 per year in Athens, London and Zaragoza, when substituting the conventional means for household energy provision (i.e. grid electricity and gas-fired boilers). Furthermore, it is demonstrated that the optimised systems outperform benchmark equivalent systems comprising conventional sheet-and-tube PVT collectors in all studied cases, by covering similar or slightly (up to 3%) higher fractions of the household electrical and thermal demands with 9–11% lower PBTs, and that PV-only solutions displace 3.56, 1.21, 1.22 tCO2/year (up to ∼20–25% lower) for the same area. Overall, the results suggest that the newly proposed polymeric flat-box PVT collector designs are an improved economic proposition over their conventional equivalents, but that the cost of this technology still remains high relative to PV and that if decarbonisation is a desirable goal, especially in high population-density regions with space restrictions, it is important to consider how to promote this technology.

Solar energy can play a leading role in reducing the current reliance on fossil fuels and in increasingrenewable energy integration in the built environment, and its affordable deployment is widely recog-nised as an important global engineering grand challenge. Of particular interest are solar energy systemsbased on hybrid photovoltaic-thermal (PV-T) collectors, which can reach overall efficiencies of 70% orhigher, with electrical efficiencies up to 15–20% and thermal efficiencies in excess of 50%, dependingon the conditions. In most applications, the electrical output of a hybrid PV-T system is the priority, hencethe contacting fluid is used to cool the PV cells and to maximise their electrical performance, whichimposes a limit on the fluid’s downstream use. When optimising the overall output of PV-T systemsfor combined heating and/or cooling provision, this solution can cover more than 60% of the heatingand about 50% of the cooling demands of households in the urban environment. To achieve this, PV-Tsystems can be coupled to heat pumps, or absorption refrigeration systems as viable alternatives tovapour-compression systems. This work considers the techno-economic challenges of such systems,when aiming at a low cost per kW h of combined energy generation (co- or tri-generation) in the housingsector. First, the technical viability and affordability of the proposed systems are studied in ten Europeanlocations, with local weather profiles, using annually and monthly averaged solar-irradiance and energy-demand data relating to homes with a total floor area of 100 m2(4–5 persons) and a rooftop area of50 m2. Based on annual simulations, Seville, Rome, Madrid and Bucharest emerge as the most promisinglocations from those examined, and the most efficient system configuration involves coupling PV-T pan-els to water-to-water heat pumps that use the PV-T thermal output to maximise the system’s COP. Hourlyresolved transient models are then defined in TRNSYS, including thermal energy storage, in order to pro-vide detailed estimates of system performance, since it is found that the temporal resolution (e.g. hourly,daily, yearly) of the simulations strongly affects their predicted performance. The TRNSYS results indicatethat PV-T systems have the potential to cover 60% of the combined (space and hot water) heating andalmost 100% of the cooling demands of homes (annually integrated) at all four aforementioned locations.Finally, when accounting for all useful energy outputs from the PV-T systems, the overall levelised cost ofenergy of these systems is found to be in the range of 0.06–0.12€/kW h, which is 30–40% lower than thatof equivalent PV-only systems