Showing papers on "Photovoltaic thermal hybrid solar collector published in 2014"
TL;DR: In this article, a review describes the rapid progress that has been made in hybrid organic-inorganic perovskite solar cells and their applications in the photovoltaic sector.
Abstract: Within the space of a few years, hybrid organic–inorganic perovskite solar cells have emerged as one of the most exciting material platforms in the photovoltaic sector. This review describes the rapid progress that has been made in this area.
5,463 citations
TL;DR: In this paper, a brief review of the energy yield losses caused by dust deposition on solar collectors, with particular emphasis on flat-panel photovoltaic (PV) systems, is presented.
380 citations
22 Jul 2014
TL;DR: In this paper, the authors proposed a general approach to radiatively lower the operating temperature of a solar cell through sky access, while maintaining its solar absorption, and demonstrated that the radiative cooling effect is substantial, even in the presence of significant convection and conduction and parasitic solar absorption in the cooling layer.
Abstract: Standard solar cells heat up under sunlight. The resulting increased temperature of the solar cell has adverse consequences on both its efficiency and its reliability. We introduce a general approach to radiatively lower the operating temperature of a solar cell through sky access, while maintaining its solar absorption. We first present an ideal scheme for the radiative cooling of solar cells. For an example case of a bare crystalline silicon solar cell, we show that the ideal scheme can passively lower its operating temperature by 18.3 K. We then demonstrate a microphotonic design based on real material properties that approaches the performance of the ideal scheme. We also show that the radiative cooling effect is substantial, even in the presence of significant convection and conduction and parasitic solar absorption in the cooling layer, provided that we design the cooling layer to be sufficiently thin.
371 citations
TL;DR: In this paper, the electrical and thermal performances of photovoltaic thermal (PVT) water collectors were determined under 500-800 W/m2 solar radiation levels, and the results showed that the spiral flow absorber exhibited the highest performance at a solar radiation level of 800-W/m 2 and mass flow rate of 0.041 kg/s.
353 citations
TL;DR: In this paper, the authors analyzed the use of energy for decentralized water production using membrane desalination systems fed with solar energy, based on experimental results from the most advanced commercial prototypes of different technologies of membrane distillation using various configurations, i.e., air-gap, permeate-gap and vacuum; with flat-plate and spiral wound membranes.
188 citations
TL;DR: In this article, a review examines the working principle, factors affecting the efficiency, and key challenges facing DSSCs, which comprises a sensitized semiconductor (photoelectrode) and a catalytic electrode (counter electrode) with an electrolyte sandwiched between them and their efficiency depends on many factors.
Abstract: Solar energy is an abundant and accessible source of renewable energy available on earth, and many types of photovoltaic (PV) devices like organic, inorganic, and hybrid cells have been developed to harness the energy. PV cells directly convert solar radiation into electricity without affecting the environment. Although silicon based solar cells (inorganic cells) are widely used because of their high efficiency, they are rigid and manufacturing costs are high. Researchers have focused on organic solar cells to overcome these disadvantages. DSSCs comprise a sensitized semiconductor (photoelectrode) and a catalytic electrode (counter electrode) with an electrolyte sandwiched between them and their efficiency depends on many factors. The maximum electrical conversion efficiency of DSSCs attained so far is 11.1%, which is still low for commercial applications. This review examines the working principle, factors affecting the efficiency, and key challenges facing DSSCs.
176 citations
TL;DR: In this paper, the performance of a flat plate PVT collector being part of a solar thermal system in a building is compared to that of standard solar devices (i.e., solar thermal collector and PV panel) through simulations using TRNSYS.
171 citations
TL;DR: In this paper, the authors investigated the integration of renewable energy sources and water systems, presenting a novel solar system producing simultaneously: electrical energy, thermal energy, cooling energy and domestic water.
167 citations
TL;DR: In this article, the authors derived up-to-date values for current and future costs of solar technologies and presented a simplified representation of system integration costs of variable renewable energies, suitable for large-scale energy-economy-climate model.
165 citations
TL;DR: In this paper, a review of the previous work on solar drying systems which implemented the phase change material (PCM) as an energy storage medium is presented, and it is concluded that the solar dryer with a PCM reduces the heat losses and improves the efficiency of the system.
Abstract: Using phase change material (PCM) as an energy storage medium is one of the most efficient ways of storing thermal energy. The latent heat storage provides much higher storage density than sensible heat storage, with a smaller temperature difference between storing and releasing heat. In addition, phase change materials provide constant and moderate temperature which is needed for drying most agriculture crops sufficiently. This paper reviews the previous work on solar drying systems which implemented the phase change material as an energy storage medium. It is concluded that the solar dryer with a PCM reduces the heat losses and improves the efficiency of the system. Furthermore, this review paper summarizes the previous methods that have been used for improving the thermal conductivity of the used phase change material particularly paraffin wax since it is commonly used as a storage medium in solar drying systems. It is inferred that carbon fibers, expanded graphite, graphite foam and high thermal conductive particles may improve the thermal efficiency of solar energy devices employing paraffin waxes as thermal energy storage media.
161 citations
TL;DR: In this paper, a single slope solar still was equipped with a flat plate solar collector, spraying unit, perforated tubes, external condenser and solar air collector for desalination.
TL;DR: In this paper, the effects of accumulation of such dirt or particle son the output performances of solar panel were analyzed under controlled conditions using spotlights to simulate source of solar radiation and it was found that the external resistance could reduce the photovoltaic performance by up to 85%.
TL;DR: In this paper, the authors identify the optimal energy production system and its optimal operation strategy required to satisfy the energy demand of a set of users in an industrial area, based on a Mixed Integer Linear Programming (MILP) model that minimizes the total annual cost for owning, maintaining and operating the whole energy supply system.
TL;DR: In this paper, the authors present the effects of nanofluids on the performance of solar collectors from the considerations of efficiency and environmental benefits, and show that the effect of different nano-fluids on cooling rate and hence the efficiency of solar systems can be experimentally investigated.
Abstract: The use of nanofluids for cooling is an attracting considerable attention in various industrial applications. Compared with conventional fluids, nanofluids improve the heat transfer rate, as well as the optical properties, thermal properties, efficiency, and transmission and extinction coefficients of solar systems. The effects of different nanofluids on the cooling rate and hence the efficiency of solar systems can be experimentally investigated. Accordingly, this review paper presents the effects of nanofluids on the performance of solar collectors from the considerations of efficiency and environmental benefits. A review of literature shows that many studies have evaluated the potential of nanofluids for cooling different thermal systems. The second part of this paper presents an overview of the research, performance, and development of photovoltaic/thermal (PV/T) collector systems. Descriptions are made on water PV/T collector types, analytical and numerical models, and simulation and experimental works. The parameters affecting PV/T performance such as covered versus uncovered PV/T collectors, absorber plate parameters, and absorber configuration design types are extensively discussed. Exergy analysis shows that the coverless PV/T collector produces the largest total (electrical+thermal) exergy. Furthermore, PV/T collectors are observed to be very promising devices, and further work should be carried out to improve their efficiency and reduce their cost. Therefore, using nanofluids for cooling PV/T systems may be reasonable.
TL;DR: In this article, the performance of concentrated solar power plants equipped with molten salts thermal storage to cover a base load of 3MWel was investigated in two locations: Gela in southern Italy and Luxor in Egypt.
TL;DR: In this article, the optimization of a solar photovoltaic thermal (PV/T) water collector which is based on exergy concept is carried out, and the optimization results are in good agreement with the experimental data of previous literature.
TL;DR: In this paper, the authors summarized the previous works on solar water heating systems with various heat transfer enhancement techniques including collector design, collector tilt angle, coating of pipes, fluid flow rate, thermal insulation, integrated collector storage, thermal energy storage, use of phase change materials, and insertion of twisted tapes.
Abstract: Solar energy is free, environmentally clean, and therefore it is accepted as one of the most promising alternative energy sources. The effective use of solar energy is hindered by the intermittent nature of its availability, limiting its use and effectiveness in domestic and industrial applications especially in water heating. Conversion of solar energy into thermal energy is the easiest and most used method. The efficiency of solar thermal conversion is around 70% but solar electrical direct conversion system has an efficiency of only 17%. Solar water heating systems are mostly suited for its ease of operation and simple maintenance. Many research papers revealed that the improvement on thermal efficiency of solar water heating systems resulted in techniques to improve the convection heat transfer. Solar water heating systems are classified into two broad categories as passive and active systems. Passive techniques have been used to improve the convective heat transfer. The techniques like insertion of twisted tapes and its geometry, etc., play a vital role to improve the performance of solar water heating systems. This review paper summarizes the previous works on solar water heating systems with various heat transfer enhancement techniques include collector design, collector tilt angle, coating of pipes, fluid flow rate, thermal insulation, integrated collector storage, thermal energy storage, use of phase change materials, and insertion of twisted tapes. This paper also discussed the methods to optimize and simulate the solar water heating systems to understand flow and thermal behavior in solar collectors that would lead to the improvement of the thermal performance of solar collectors.
TL;DR: In this article, the authors provide an overview of the working principles of solar thermally operated cooling technologies and reviews for advancements of such technologies from the most recent publications, which is a good example of addressing climate changes.
Abstract: Solar cooling is a good example of addressing climate changes. In this paper, we provide overviews for working principles of solar thermally operated cooling technologies and reviews for advancements of such technologies from the most recent publications. Researches of solar absorption cycles investigated new refrigerant–absorbent pairs and various system configurations that could lead to increasing solar fraction and extending the cycle operation. Researches of solar adsorption cycles focused on the development and testing of various adsorbent–refrigerant pairs, improving cycle components, and increasing the system efficiency. For the ejector cycles, many studies focused on using computer models and experimental works to investigate the performance of the ejector and find the key parameters affecting its operation. Although many researches have conducted for solar thermal cooling technologies, their overall efficiencies are lower than that of the vapor compression cycles. Therefore, improving efficiency of solar thermally operated cooling technologies is an essential future research topic.
TL;DR: The integrated solar combined cycle system (ISCCS) is one of the more promising hybrid configurations for converting solar energy into electricity and it might become the technology of choice in the near future as discussed by the authors.
Abstract: The huge amount of solar energy available on Earth׳s surface has heightened awareness in Concentrating Solar Power, and more particularly in hybrid concepts. The integrated solar combined cycle system (ISCCS) is one of the more promising hybrid configurations for converting solar energy into electricity and it might become the technology of choice in the near future. This article reviews the R&D activities and published studies since the introduction of such a concept in the 1990s. The review includes the current status and describes different hybridizations of solar energy with natural gas, coal and other renewable energy sources. Furthermore, it provides in-depth analysis of real and expected R&D finding.
TL;DR: In this paper, the effects of high temperature and exposure to UV light on the optical transmittance of the heat transfer fluid under accelerated lifetime test conditions were analyzed, and it was shown that the optimum fluid for the application is the industrial grade Propylene Glycol adapted with a chemically-inert red dye such as Oil Red 235 inorganic dye.
TL;DR: In this paper, a theoretical model for evaluating the efficiency of concentrating PV-TE (photovoltaic-thermoelectric) hybrid system is developed, and the influence of temperature on the efficiency has been taken into account based on the semiconductor equations.
TL;DR: In this article, the authors consider cooling systems for residential and utility buildings in both South and North Europe and investigate the most promising alternatives when solar energy is to be used to supply the cooling demand of these buildings while the heat rejection temperatures are high.
Abstract: Solar energy can potentially contribute to 10% of the energy demand in OECD countries if all cooling and heating systems would be driven by solar energy. This paper considers cooling systems for residential and utility buildings in both South and North Europe and investigates the most promising alternatives when solar energy is to be used to supply the cooling demand of these buildings while the heat rejection temperatures are high. Both the solar electric and solar thermal routes are considered. The discussion considers both concentrating and non-concentrating thermal technologies. It is concluded that presently vapor compression cycles in combination with PV collectors lead to the economically most attractive solutions. The second best option are vapor compression cycles driven by electricity delivered by parabolic dish collectors and Stirling engines. The best thermally driven solution is the double-effect absorption cycle equipped with concentrating trough collectors closely followed by desiccant systems equipped with flat-plate solar collectors. Adsorption systems options are significantly more expensive.
TL;DR: In this paper, the Second Law analysis of a water-cooled hybrid photovoltaic/thermal collector is presented, based on simulations, and a thermoeconomic analysis is carried out to define the price of the thermal energy produced by the PVT collector, as a function of its exergy content.
TL;DR: In this paper, the authors investigated the dynamic performance of a novel solar photovoltaic/loop-heatpipe (PV/LHP) heat pump system for potential use in space heating or hot water generation.
TL;DR: In this article, a novel ceiling ventilation system integrated with solar photovoltaic thermal (PVT) collectors and phase change materials (PCMs) is proposed to improve indoor thermal comfort of passive buildings without using air-conditioning systems.
TL;DR: In the first commercial projects involving parabolic-trough technology, some improvements are being introduced like the use of large molten-salt heat storage systems able to provide high degrees of dispatchability to the operation of the plant, like the plants Andasol in Guadix, Spain, with 7.5h of nominal storage and air, or direct steam generation loops to replace thermal oil at the solar field as discussed by the authors.
Abstract: Solar thermal concentrating solar power (CSP) plants, because of their capacity for large-scale generation of electricity and the possible integration of thermal storage devices and hybridization with backup fossil fuels, are meant to supply a significant part of the demand in countries of the solar belt. Nowadays, the market penetration of solar thermal electricity is steeply increasing, with commercial projects in Spain, USA, and other countries, being the most promising technology to follow the pathway of wind and photovoltaics to reach the goals for renewable energy implementation in 2020 and 2050. In the first commercial projects involving parabolic-trough technology, some improvements are being introduced like the use of large molten-salt heat storage systems able to provide high degrees of dispatchability to the operation of the plant, like the plants Andasol in Guadix, Spain, with 7.5 h of nominal storage, or the use of direct steam generation loops to replace thermal oil at the solar field. In the near future, the research and innovation being conducted within the field of linear Fresnel collectors may lead to high temperature systems able to operate up to 500°C and produce cost-effective superheated steam. Central receiver systems are opening the field to new thermal fluids like molten salts (Gemasolar tower plant in Seville, Spain) with more than 14 h of nominal storage and air, and new solar receivers like volumetric absorbers, allowing operation at temperatures above 1000°C. All these factors can lead to electricity generation cost reduction of CSP plants by 30–40% for the period 2010–2020, according to public roadmaps and cost analysis made by the International Energy Agency in 2010. WIREs Energy Environ 2014, 3:42–59. doi: 10.1002/wene.79
The authors have declared no conflicts of interest in relation to this article.
For further resources related to this article, please visit the WIREs website.
TL;DR: In this article, a prototype open loop air-based building integrated photovoltaic thermal BIPV/T system with a single inlet is studied through a comprehensive series of experiments in a full scale solar simulator recently built at Concordia University.
TL;DR: In this paper, an attempt has been made for evaluating thermal, electrical and exergy output of solar PV panel installed at Energy Centre, NIT Bhopal using the first law of thermodynamics.
Abstract: The solar photovoltaic (PV) system generates both electrical and thermal energy from solar radiation. In this paper, an attempt has been made for evaluating thermal, electrical and exergy output of solar PV panel installed at Energy Centre, NIT Bhopal. Using the first law of thermodynamics, energy analysis was performed and exergy analysis was carried out to determine exergy losses during the PV conversion process by applying the second law of thermodynamics. The operating and electrical parameters of a PV array include PV module temperature, overall heat loss coefficient, open-circuit voltage, short-circuit current, fill factor, etc. were experimentally determined for a typical hazy day of March (10 March 2012) at Bhopal. The experimental data are used for the calculation of the energy and exergy efficiencies of the PV systems. Energy efficiency is seen to vary between 6% and 9% during the day. In contrast, exergy efficiency is lower for electricity generation using the considered PV module, ranging from...
TL;DR: In this paper, a comparative study for thermal and electrical performance of different hybrid photovoltaic/thermal collectors designs for Iraq climate conditions have been carried out, where four different types of air based hybrid PV/T collectors have been manufactured and tested.
TL;DR: In this paper, performance assessment of a co-generation system is presented to deliver electrical and thermal energy using the solar energy and the reversible solid oxide fuel cell, and a mathematical model of the co-generative system is developed.