Collector Panels Research Articles

Research on New Energy-saving and Efficient Utilization of Buildings Based on Renewable Energy

Against the background of the increasing total energy consumption and the proportion of energy consumption in China, the energy crisis is intensifying. The application of renewable energy such as solar energy, wind energy and geothermal energy to building energy conservation is a major decision to solve the energy problem of buildings. The thesis combines the theories of green building evaluation standards, the problems facing the use of renewable energy, the value expression and use of renewable energy, and the impact of renewable energy on green building research. The influence of outdoor buried pipe layout and the arrangement of heat collector panels in the solar system on the feasibility research method in green building research, with a view to providing a certain reference for the subsequent research of new green residential projects in China.

Experimental and numerical analysis of solar-absorbing metallic facade panel with embedded heat-pipe-array

The integrative performance of advanced building façade is important for sustainable building development. This paper introduces two solar-absorbing curtain-wall panels with embedded straight-heat-pipe and heat-pipe-ring respectively. Taking advantage of the high thermal conductance of heat pipe, the proposed solar-absorbing aluminum panels can preheat cold water, like for the domestic hot water supply. They also reduce the solar transmission to the indoor space. In hot summer, the dual effect leads to considerable energy saving in both the hot-water and the air-conditioning systems. Comparing with the water-tubing collector panel, the heat-pipe type has wider application by eliminating the water-freezing problem. The conceptual design, prototype construction and computer-model development of these two panels are discussed in this paper. Measurements were taken with the two prototypes installed at an outdoor environmental chamber. Dynamic simulation models were then developed through the control volume finite difference method, and validated with the measured data. The simulation models can be used in advanced building simulation tools for transient thermal performance analysis. Further numerical analysis with these models showed that comparatively, the innovative heat-pipe-ring is the more promising design because of the effective increase in solar absorbing surface area. In the studied warm climate scenarios from summer to winter and from sunny to cloudy conditions, the water heat gain efficiency was estimated from 62.5% to 94.9% in all cases with the glazed panel. The estimated room heat gain/loss as well as the electricity saving performance are also attractive.

Dynamic and Economic Investigation of a Solar Thermal-Driven Two-Bed Adsorption Chiller under Perth Climatic Conditions

Performance assessment of a two-bed silica gel-water adsorption refrigeration system driven by solar thermal energy is carried out under a climatic condition typical of Perth, Australia. A Fourier series is used to simulate solar radiation based on the actual data obtained from Meteonorm software, version 7.0 for Perth, Australia. Two economic methodologies, Payback Period and Life-Cycle Saving are used to evaluate the system economics and optimize the need for solar collector areas. The analysis showed that the order of Fourier series did not have a significant impact on the simulation radiation data and a three-order Fourier series was good enough to approximate the actual solar radiation. For a typical summer day, the average cooling capacity of the chiller at peak hour (13:00) is around 11 kW while the cyclic chiller system coefficient of performance (COP) and solar system COP are around 0.5 and 0.3, respectively. The economic analysis showed that the payback period for the solar adsorption system studied was about 11 years and the optimal solar collector area was around 38 m2 if a compound parabolic collector (CPC) panel was used. The study indicated that the utilization of the solar-driven adsorption cooling is economically and technically viable for weather conditions like those in Perth, Australia.

Development of a solar colleсtor based on aluminum construction heat pipes

The object of research is the thermal efficiency of solar collectors based on aluminum structural heat pipes. Solar collectors with heat pipes have a structurally similar design. The heat-absorbing panel secures the heat pipes to the evaporation zone, and the condensation zones are located in the battery tank. The differences are only in the designs of the absorption panels, the areas of the condensation zones and the heat carriers of the heat pipes. One of the most problematic places of research is the justification and development of a new design of a heat-absorbing solar collector panel based on heat pipes.A review of the publications showed that a solar collector based on aluminum structural heat pipes operating in the two-phase thermosyphon mode has a heat loss when transmitting radiation heat exchange in the long-wavelength range between the absorbing flat panel and the heat pipe. The project of a solar collector with a new, absorbing solar rays panel is proposed. To analyze the efficiency of the solar collector based on aluminum structural heat pipes with a new absorption panel, two models of solar collectors were created – with a flat absorber panel and a cylindrical absorber panel.The models of solar collectors based on one aluminum structural heat pipe fixed on aluminum flat and aluminum cylindrical absorption surfaces are investigated by the method of thermophysical experiment.The results of studies of the efficiency of solar collector models are presented. The thermal efficiency of a new solar collector based on an aluminum structural heat pipe with a cylindrical absorbing panel in the initial period of heating water is up to 1 5 % higher than that of a solar collector with a flat absorbing panel, and at the end of heating up to 4 %. The cylindrical surface of the panel plays the role of a concentrator of the reflected part of the radiation and the own radiation of the panel in the region of the heat pipe.Further studies are planned to be conducted in the direction of optimization of the geometric parameters of the heat-absorbing surfaces of solar collectors.

Energy performance enhancement of a collective hot water production process equipped with a centralized storage tank

This paper investigates the thermal performance of a forced circulation collective solar water heater (SWH) equipped with a centralized storage tank, throughout hourly dynamic simulations. The main purpose of this study is to identify the parameters affecting the overall efficiency of the collective process, because the literature review focuses on individual SWHs, rather than collective hot water systems that are extensively integrated in the tertiary sector, such as hotels, hospitals, university residences, etc. Hence, being able to suggest general recommendations that would be helpful to guide hot water system designers. A typical residence located in Fez city (Morocco) that shelters 60 occupants was considered as a realistic case study, for which the thermal performances of the collective hot water production system were simulated. Several performance indicators were defined and miscellaneous dynamic simulations were carried out to enhance the process's efficiency. For instance, the incident energy on the solar collector panel, the supplementary consumptions for different storage tank volumes and load profiles, the useful energy gain from the collector's field and the solar fraction of the collective hot water process. The results showed that the Evacuated Tube Technology (ETC) is suitable for this collective hot water production application, because the solar fraction of the process remains higher with ETC, as opposed to the use of Flat Plate Collectors (FPC). Moreover, increasing the centralized storage tank volume enhances the annual solar fraction of the collective hot water process. Last but not least, the maximal annual averaged solar fraction was achieved by the ETC technology (78%). However, it is equal to 68% for (FPC) while maintaining 3000 l as a centralized storage capacity.

Design of Solar Power LED Lighting System using Horizontal Two-Axis Arduino Based Solar Tracking System

The project deals with design of solar power LED lighting system using Horizontal Two-Axis Arduino based Solar Tracking System. The main goal of this project is to design a very precise solar tracker. The project is divided into two parts; hardware and software. Hardware part generally composed of solar panel, two-DC motors with gearbox, LDR sensor module and electronic circuit. Software part represents the thinking behavior of the system, that is how the system acting under several weather conditions. In this work sensing of the sun position carried out in two stages primary and secondary. Primary stage or indirect sensing performed via sun-earth relationship as a coarse adjustment and second stage or direct sensing performed via set of LDR sensors as output tuning to trims the azimuth and altitude angles. If the weather is cloudy or dusty, the tracking system uses primary stage or sun-earth geometrical relationships only to identify the location of the sun; so the system tracks the position of the sun regardless the weather condition. The energy extracted from photovoltaic (PV) or any solar collector depends on solar irradiance. For maximum extraction of energy from the sun, the solar collector panel should always be normal to the incident radiation Solar trackers moves the solar collector to follow the sun path and keeps the orientation of the solar collector at an optimal tilt angle. Solar tracking system improves substantially the energy efficiency of photovoltaic (PV) panel. In this paper, an automatic dual axis solar tracking system is designed and developed using Light Dependent Resistor (LDR) and DC motors on a mechanical structure with gear arrangement. Two axis solar tracking (azimuth angle as well as altitude angle) is implemented through Arduino UNO controller based on Sun Earth Geometry. The results indicated that the automatic solar tracking system is more reliable and efficient than fixed one.

Optimization of a hybrid energy plant by integrating the cumulative energy demand

This paper deals with the optimal design of a hybrid energy plant, which can include the following energy systems: solar thermal collector, photovoltaic panel, hybrid photovoltaic/thermal solar system, combined heat and power system, organic Rankine cycle, absorption chiller, air source heat pump, ground source heat pump and thermal energy storage. Three different configurations are analyzed. In the first configuration, the abovementioned systems are considered with the exception of the hybrid photovoltaic/thermal solar system and organic Rankine cycle. In the second configuration, a hybrid photovoltaic/thermal solar system is also included and in the third configuration the use of an organic Rankine cycle as the bottoming cycle of the combined heat and power system is evaluated. The optimization goal is to minimize the primary energy demanded throughout the manufacturing and operation phase of the hybrid energy plant. The challenge of non-linear life cycle inventory scaling of energy systems is also addressed. A tower located in northern Italy is selected as a case study and two different approaches are evaluated. The first approach consists of solving the sizing optimization by minimizing primary energy consumption only during the operation phase, while in the second approach primary energy consumption is minimized throughout the life cycle of the plant by integrating the life cycle assessment into the optimization process. The results show that, if life cycle assessment is integrated, the optimal sizes of plant components are different and the primary energy saving throughout the life cycle is always higher. With reference to the LCA integrated approach and compared to the first configuration, the use of a hybrid photovoltaic/thermal solar system instead of separate solar thermal collector and photovoltaic panels is more efficient and may allow a primary energy saving of about 4%. Furthermore, compared to a conventional plant, the primary energy saving achievable with the first configuration is approximately 14%, while the primary energy saving increases to about 17% for the second and third configurations.

태양광열 패널의 성능 예측을 위한 실험 연구

태양광열 패널의 성능 예측을 위한 실험 연구

Anti-reflective and anticorrosive properties of laser-etched titanium sheet in different media

The effects of femtosecond laser etching in different media (air, deionized water, and anhydrous ethanol) on the morphology, anti-reflection, and anticorrosion of titanium sheet surface were studied. Ripples, ripples overlapped by grooves and micro-bumps, were, respectively, obtained by laser etching in the air, ethanol, and water. Compared to the untreated titanium, on the surface of titanium sheet, Ti6O and Ti3O are obtained by laser etching in water, but Ti6O was obtained by laser etching in ethanol. The reflectivity of laser-etched Ti surface in ethanol or water is reduced to less than 17% within the 200 nm–1200 nm spectral range. The etched surface in ethanol shows better reflectivity in the ultraviolet–visible range with a minimum value of 3%, and the etched surface in water exhibits better anti-reflection performance in the near-infrared spectral range 800 nm–1200 nm with the lowest value of 7.6%. The differences of anti-reflection are ascribed to the competition between the light trapping effects and the effective medium effect. Furthermore, the anticorrosion property of titanium is also improved by laser etching in water or ethanol. Ecorr of the laser-etched samples is about 0.05 v higher than that of untreated Ti, while Icorr is reduced by about 0.5 order of magnitude. The better anticorrosion is mainly due to the improved hydrophobicity in 3.5% NaCl solution. The improvement of these properties allows titanium to have more important application value in solar collector panels, optoelectronic devices, thermal photovoltaic power generation, and so on.

Hardware and Software Components of an Oysters' Gape Measurement System

In this work, the hardware and software used in developing a bivalve gape measurement system is explored. This system employs the Hall-effect phenomenon to accurately measure and report the gape of a bivalve. The system uses a Hall Effect sensor (Symmetry Electronics’ H2425) and a small magnet in which both are glued to the exterior of the shells of a bivalve. Consequently, the Hall Effect sensor reports the distance of the magnet, hence the gape opening, to a microcontroller that records and transmits the data to a ground station. This system has been designed to operate in the field as well as in a laboratory environment. In a laboratory setting, this system uses Wi-Fi or Bluetooth to transmit its data. In the field however, due to the lack of availability of power, two setups have been established. The first setup does not transmit data, instead, it saves the data in an SD card within the system’s enclosure. This setup is fully submersible. The battery, microcontroller and SD card reader are all submerged alongside the bivalve. This experiment shows that the system can work for as long as 29 days with a single battery charge. Therefore, each month the battery of this system will have to be replaced if data collection is to continue. The second field system is one that wields cellular network to communicate its data. This is a viable solution since most reefs exist close enough to the shore where cellular signal is available. Additionally, the system includes a solar collector panel for charging the battery during the day and constantly keeping the system transmitting at night. The laboratory system as well as the underwater field system are both fully operational and have been producing gape data for several months. The cellular system is currently being tested and data from all systems will be made available under the MBRACE project data repository.

Application of phase-change material in solar hot-water system

In this paper, hydrated salts of disodium hydrogen phosphate dodecahydrate and disodium sulfate decahydrate are employed to compose a composite hydrated salt with a ratio of 9·5:0·5. The composite hydrated salt has been used as a phase-change thermal storage material in a solar hot-water system to study the effect of phase-change material on the thermal conversion efficiency of such a system. The phase-change material is packaged in a plastic container. The experimental results show that the thermal conversion efficiency is significantly affected by the amount of thermal storage medium and solar radiation intensity. The solar thermal conversion efficiency for the 2 m2 solar panel collector could reach up to 66·4% for a thermal storage medium consisting of 38·1 kg phase-change thermal storage material and 124·7 kg water and with an averaged radiation intensity of 1243 w/m2, even at lower ambient temperatures between −7·0°C in the morning and 1·0°C at 15:00. It indicates that the use of phase-change materials in a solar water-heating system could improve the solar thermal conversion efficiency of such a system.

Design of a New Solar Thermal Collector with Ceramic Materials Integrated into the Building Facades

The work presented here aims to demonstrate the technical, architectural, and energy viability of solar thermal collectors made with ceramic materials and their suitability for domestic hot water (DHW) and building heating systems in the Mediterranean climate. The proposal is for the design of a ceramic shell, formed by collector and non-collecting panels, which forms part of the building system itself, and is capable of responding to the basic requirements of a building envelope and harnessing solar energy. Ceramics considerably reduce the final cost of the collector system and offer the new system a variety of compositional and chromatic finishes, occupying the entire building surface and achieving a high degree of architectural integration, although less energy-efficient compared to a conventional metallic collector.

Overheating protection of solar thermal façades with latent heat storages based on paraffin-polymer compounds

A prototype façade element equipped with an integrated solar thermal collector and latent heat storage panels for thermal protection of the interior is tested in a solar simulator. Therefore, latent heat storage panels based on polymeric materials are specifically designed and mounted in the insulation of a solar thermal façade collector. The panel position and thickness (stacking) are optimized. The overheating protection efficiency of the optimized configuration is high: even at a harsh solar irradiation, the inner surface and interior air temperatures do not exceed comfort levels. The discharging and full regeneration of the latent heat storage during the night is evident. The results emphasize a high innovative capacity of polymeric latent heat storages and prove the overheating protection concept of preceding numerical simulations.

Design and thermal performance optimization of a forced collective solar hot water production system in Morocco for energy saving in residential buildings

This paper presents a comprehensive study that aims to assess the energetic performances of a solar hot water collective system under a realistic load consumption profile in Morocco. The case study which has been considered in this work is a residential building located in Fez city. Several parameters are involved into the performance assessment of the collective system. Hence, it was essential to identify the parameters on which we will act in order to carry out the parametric study. In fact, the technology of evacuated tube collectors (ETC) with heat pipes were selected as a fixed study parameter, while a set of other indicators were investigated contributing to the collective hot water system design and optimization, such as the solar collector panel total area, the connecting methods between the collector’s field which could be serial, parallel or mixed connection, the collective hot water storing volume configurations in addition to the intrinsic optical efficiencies of the world’s manufacturers solar collectors. In order to achieve the assessment of the energetic performances of the collective system, four parametric studies were described and carried out to ensure its design and optimization during the dynamic mode operation.The most relevant findings from this research paper are presented as follows. Incrementing the collector’s field area to 120 m2 optimizes the thermal efficiency of the collective system, and the hydraulic booster consumption is reduced. Besides, it would be advantageous to use a total area of 80 m2 to satisfy the hot water need demand over the four seasons, since the overall collective system thermal efficiency remain above 60%. Moreover, is was possible to ensure a seasonal solar fraction which is greater than 50% by connecting a collective storage tank with a volume of 1500 l and a solar collector panel with an area of 100 m2. Last but not least, the effect of the row’s number as well as the number of collectors connected per row on the overall collective system’s solar fraction was also investigated through this study.

Building integrated solar air heating with waste heat utilization

A novel waste heat utilization system, which consists of transpired solar collector panels and capillary tube heat exchanger, is studied; its function principle is described, and its experimental performance is presented for the first time. A test unit of capillary tubes was installed at the solar wall air heater at the factory of an automotive company in Turkey in 2012. Capillary tubes utilized waste heat energy which is obtained from heat recovery unit of an air compressor. Thermal power output, ambient temperature, temperature rise, collector cavity temperatures, and water supply temperatures were monitored over the course of two winters. The results showed that capillary tubes can provide 15 °C temperature rise during night-time operation. The heat exchange effectiveness in air cavity is found to be maximum 0.7. The results also show that waste heat energy utilization can reach up to 85% depending on operating conditions.

Different parameter and technique affecting the rate of evaporation on active solar still -a review

Water is one of the essential sources for the endurance of human on the earth. As earth having only a small amount of water resources for consumption purpose people in rural and urban areas are getting affected by consuming dirty water that leads to water-borne diseases. Even though ground water is available in small quantity, it has to be treated properly before its use for internal consumption. Brackish water contains dissolve and undissolved contents, and hence it is not suitable for the household purpose. Nowadays, distillation process is done by using passive and active solar stills. The major problem in using passive solar still is meeting higher demand for fresh water. The fresh water production from passive solar still is critically low to meet the demand. To improve the productivity of conventional solar still, input feed water is preheated by integrating the solar still to different collector panels. In this review article, the different parameters that affect the rate of evaporation in an active solar still and the different methods incorporated has been presented. In addition to active distillation system, forced convection technique can be incorporated to increase the yield of fresh water by decreasing the temperature of cover. Furthermore, it is identified that the yield of fresh water from the active desalination system can be improved by sensible and latent heat energy storage. This review will motivate the researchers to decide appropriate active solar still technology for promoting development.

Evaluation of a solar thermal glass façade with adjustable transparency in cold and hot climates

The paper presents the evaluation of a new glass façade system, titled FLUIDGLASS, which combines four functions in one element: a solar thermal collector, a heating/cooling device, a transparent thermal envelope and an adaptive shading system. The collector panel is a combination of fluid and glass layers. By controlling the temperatures or the transparency of the circulating fluid the passive façade is transformed into an active thermal system capable of reacting to changing environmental conditions. The expected impact is a significant improvement in the thermal performance of the building envelope and high thermal comfort for different climate zones. The validation by simulation and measurement results indicate that no additional energy beyond that which is provided by the façade element is necessary to reach the thermal comfort temperatures. Surpluses of solar collector gains can contribute to the usage on a district level with seasonal storage.

Efficiency analysis of tank-type water distillation system integrated with hot water collector

In this study, besides the hot water, it was also aimed to obtain distilled water from solar still water heating systems, which are widely used in obtaining hot water. For this purpose, a new type of distiller was obtained by making modifications, which enable us to obtain distilled water, on a solar still water heating system having flat-surface panel collector and vertical tank and operating as a closed system. The designed system was tested under both natural convection and forced convection at flow rates of 30kg/h and 50kg/h. As a result of performed experiments, the temperature, productivity, and distilled water production amounts were calculated for the designed system. It was determined that the temperature of hot water obtained was sufficient for daily use. According to the results, as the highest amount of water, 1.820kg/day distilled water was obtained form also the natural convection system. In order to determine the drinkability of distilled water, the laboratory analyses were carried out, and it was found that the water meets EC standards. Thus, the clean and hot water was obtained at the same time from the designed system under real weather conditions.

A REVIEW OF EXPERIMENTAL STUDY OF POWER QUALITY MEASUREMENT OF PHOTOVOLTAIC CELLS WITH MAXIMUM POWER POINT TRACKING SYSTEM

Maximum power point tracking (MPPT) is a technique that charge controllers use for wind turbines and PV solar systems to maximize power output. PV solar systems exist in several different configurations. The most basic version sends power from collector panels directly to the DC-AC inverter and from there directly to the electrical grid. A second version, called a hybrid inverter, might split the power at the inverter, where a percentage of the power goes to the grid and the remainder goes to a battery bank. The third version is not connected at all to the grid but employs a dedicated PV inverter that features the MPPT. In this configuration, power flows directly to a battery bank.

Determination of Solar Collector Optimum Tilt Angle for Ankara and Districts

This study that is Ankara province and districts based deals with the determination of the optimum tilt angle to maximize the performances of solar collector and solar panel. In Ankara, fixed solar collectors are usually placed at slope of 40°. In this study, annual optimum tilt angle for Ankara province and districts was calculated as 34°±1 however the optimum angles during the year were calculated between 1° and 67°. The results of this study are compared with similar studies in the literature they were found to be consistent with the results of similar studies. Also, the tilt angle was calculated for the six months periods as 15° and 56°, for seasonal periods (winter, spring, summer, autumn) as 62°, 23°, 6° and 49°, respectively and solar radiation for optimum angles of inclination were found. When the tilt angle is changed only twice a year, due to increasing the amount of energy per unit area, according to the annual tilt angle fixed product they provides energy efficiency by about 5%. On the other hand, when the tilt angle is changed every month this ratio can be reached approximately 8%. For increasing the utilization efficiency of solar collectors and panels, it is recommended adjusting of the tilt angle once a month or at least twice a year.