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Solar Engineering of Thermal Process
... In this part, our objective is to determine the thermal power lost by the receiver and the useful thermal power. The power lost by the receiver ( ) can be determined by iteration from its three expressions [9]: 20) ...
... In the same way, the useful power recovered by the fluid ( ) is given by [9]: ...
... Xiao [13] shows that for latitudes less than 25 °, an orientation of north-south Tracking axis offers better efficiency. Finally, Duffie and Beckman [9] recommends a spacing between the absorber tube and the glass tube between 10 mm and 15 mm to minimize the thermal losses of the receiver. In addition, water was chosen as a thermal fluid. ...
The aim of this work is to study a Linear Fresnel Plant (LFP) in rural Sahelian areas. An analytical method is used to model optical transfers in the system, followed by a sizing using MATLAB software. Then, the analytical method is compared with the Monte Carlo method using TONATIUH rays trace software. And finally, the optical characteristics of the LFP over the period from December to April are studied by simulation using TONATIUH. The design gives for a thermal power of 51.01 kW an opening area of the LFP field equal to 109.04 m 2 with a coverage rate of 75.41%. The comparison of the analytical method with that of ray tracing confirms the validity of the analytical method for the calculation of power. As expected, numerical simulations show for each day a peak of the power received around 13 h, and optical efficiency of the field increase from December to April.
... Salah satu sumber energi baru terbarukan yang berkembang pesat dan berlimpah jumlahnya serta gratis adalah energi matahari. Bumi mendapatkan 16x10 18 Joule dari matahari setiap tahunnya, atau setara dengan 20.000 kali dari kebutuhan seluruh umat manusia di bumi [3]. Indonesia merupakan sebuah negara yang posisinya terletak di khatulistiwa dan memperoleh energi matahari sebanyak 4,8-6,0 kWh/m 2 tiap tahunnya [4]. ...
... Adalah waktu yang berdasarkan pergerakan semu matahari di langit pada tempat tertentu. Jam matahari (disimbolkan ST) berbeda dengan penunjukkan jam biasa (standard time, disimbolkan STD) [18]. Untuk mencari STD digunakan persamaan yang ditetapkan oleh Duffie dan Beckman [18]: ...
... Jam matahari (disimbolkan ST) berbeda dengan penunjukkan jam biasa (standard time, disimbolkan STD) [18]. Untuk mencari STD digunakan persamaan yang ditetapkan oleh Duffie dan Beckman [18]: ...
The current need for electrical energy sourced from fuel oil is increasingly running out and expensive. Anticipating future energy crises will require creativity from energy observers in finding alternative energy sources that can improve people's welfare. We get solar energy for free throughout the year with good intensity, one of which is because Indonesia's position is on the equator. To convert solar heat from the outside into electrical energy, several converter technologies such as solar panels are needed. Solar panels that are directly exposed to solar radiation can produce efficient electrical energy depending on the position of the incident light that hits the surface of the solar panel. Solar panels that can follow the direction of the radiation source at an angle of 90o to the surface of the solar panel must require a solar tracker. Solar tracker is a control circuit that is able to detect and follow the direction of the sun so that the solar panel is always perpendicular to the sun so that the light intensity received by the panel is optimal by adjusting the motor movement. The results of this study indicate a light intensity of 408.10 W/m2 at a wind speed of 1.08 m/s produces a current of 19.20 Volts with an efficiency level of 4.21% at the incoming energy (Pin) 279.05 and the outgoing energy ( Pout) 11.77 W.
... The RETScreen calculation method is an improved form of the previous methodology given by some researchers in the literature [42,43]. The algorithm uses an approach similar to Klein and Theilacker's algorithm [25] described by Duffie and Beckman [44] for fixed-tilted PV surfaces. On the other hand, the algorithm is extended to solar tracking systems to investigate maximal radiation in the one-axis, and two-axis constructed solar PV surfaces as described by Braun and Mitchell [33]. ...
... The sunset hour angle, s is the angle between the longitude of the sun's rays and the longitude of the place under consideration. It can be calculated for the horizontal plane by setting the cosine of the zenith angle to 0° [44] in the following expression: ...
... Several isotropic transposition models are developed to determine hourly (tilted) radiation falling on the PV surface H t . In this study, Liu and Jordan's isotropic method is preferred to estimate total solar radiation falling on tilted south-faced PV surfaces [22,44,51] specifically given by Beam radiation tilt factor R b is a function of atmospheric permeability based on solar climatic conditions the cloudiness index, water vapor, and atmospheric particle density. It is the ratio of monthly average daily beam radiation falling on a tilted surface to a horizontal surface as follows: ...
The solar photovoltaic (PV) plants in Türkiye have been advancing at a remarkable rate in the last decades because of the region’s high solar energy potential. However, it is understood from the literature review that there are still limited research works on the optimization of the tilt angles of PV surfaces to maximize the solar radiation of the PV energy systems in this region. Therefore, this study focuses on a quantitative analysis of the optimal tilt angles of south-oriented PV surfaces and the amount of solar radiation collected by optimally tilted and tracked PV surfaces for all provinces by using the National Aeronautics and Space Administration-Surface meteorology and Solar Energy (NASA-SSE) horizontal radiation data for the provinces in Türkiye. Also, a numerical method is proposed to estimate the average daily solar radiation values falling on optimally tilted and tracked PV surfaces in 81 provinces and 7 geographical regions of Türkiye in this paper. An optimal tilt angles map has been created for all provinces where solar plants could be established. Solar data calculations have been carried out for all provinces, and the results are presented for the average total radiation amounts and percentage contributions that can be obtained in the case of installing fixed systems and tracking systems. It is found that the tilt angles of all provinces and regions are below the latitude values of Türkiye (36°′N–42°′N). Annual fixed optimal tilt angle values for south-facing PV surfaces are found between 28° and 36° throughout the year. It is observed that the daily average total radiation values falling on PV surfaces are considerably affected by the geographical and climatic characteristics even between the provinces with close latitude values in Türkiye. The results indicate that the tracking systems provide remarkable solar energy gains compared to the annual fixed systems. The proposed methodology can be used in the case of the implementation of a large-scale PV plant in any location in Türkiye, and this knowledge can be extended to the world thanks to low computational cost.
... The hourly total radiation to the tilted surface located at the declination angle of β could be determined using the Hay model, as given by Eq. (1) [25] which also validated experimentally [30,31]; ...
... (1), represents the reflective coefficient of the surrounding surface and its value depends on the type of surface around the collector [25]; considering the ground-type mosaic flooring, the value of 0.2 taken for the magnitude of albedo coefficient [36]. The geometric coefficient denotes the direct radiation on an inclined surface to that on the horizontal surface and is given by Eq. (7). ...
The application of solar energy as the widest, clean and free source of thermal energy requires the solar collector. As one of the common types of solar collector, heat pipe solar collector has been investigated. The thermal performance of a solar heat pipe collector was simulated using the anisotropic sky radiation model in eight different tilt angles and thirteen azimuth angles at the location of Isfahan City, Iran. The obtained theoretical results were compared with experimental ones and an average discrepancy of 5 % was obtained. After approving the chosen model, the optimum seasonal and yearly tilt angles were calculated and the correlations also were drawn from a written subroutine. The results show that through spring and summer, the optimum tilt angle is somewhat less and through autumn and winter the optimum tilt angle is beyond the latitude angle with the largest difference in spring and autumn. For the whole year and under the conditions of the present study, the optimum tilt angle is nearly the same as the latitude angle of the location. Abbreviations 3 dimensional 3D Collector surface area (m 2) A specific heat (kJ/kg.K) cp (A. Alizadeh), Fazililati@iaukhsh.ac.ir (M. Fazilati). Note: Low-resolution images were used to create this PDF. The original images will be used in the final composition. D. Wei et al. Case Studies in Thermal Engineering xxx (xxxx) 104083 Solar radiation flux (W/m 2) G Heat pipe HP global horizontal solar irradiation I sky clearance index KT mass (kg) m day number n Photovoltaic/thermal PV/T absorbed heat (kJ) Radiation flux (W/m 2) R geometric coefficient Rb temperature (o C) T time (minute) t Greek symbols collector tilt angle β difference surface azimuth angle γ latitude angle φ reflectivity ρ regular incident angle θ incident angle with β = 0 θ z
... where ε eff is the effective emissivity factor of diffuse radiation from the water surface to the interior surface of the glass cover and σ is the Stefan-Boltzmann constant taken as 56.7 × 10 −9 Wm −2 K −4 [27]. If the shape factor is taken as the unity and the emissivity of the water is 0.90, the radiative heat transfer from the hot water surface to the interior surface of the glass cover can be determined using Equation (13). ...
... Hence, the overall heat transfer coefficient (U t ) through the top of the still can be calculated using Equation (27). The rate of conductive heat losses q b in (W) from the basin bottom to the atmosphere can be formulated using Equation (28) [33,34]. ...
The conventional solar still (CSS) unit faces challenges such as low productivity (Pd) and thermal efficiency (ηth) due to the limited temperature difference between the hot water and the cold interior glass cover surfaces (ΔTw-gi). This study addresses these issues by introducing enhancements in the CSS unit, incorporating a v-corrugated-type basin, internal reflecting mirror, flat-plate solar collector (FPSC) still, and FPSC nanofluids. A v-corrugated-type basin, internal reflecting mirror, FPSC still, and FPSC nanofluids elicited a significant improvement in the distillate productivity (Pd) up to approximately 22.39%, 41.72%, 70.10%, and 104.13% compared to the CSS unit. This increase in the Pd is attributed mainly to a notable raise in the ΔTw-gi, showing increments of around 34.33%, 52.32%, 77.37%, and 112.87% compared to the CSS unit. Moreover, a v-corrugated basin, internal reflecting mirror, FPSC still, and FPSC nanofluids substantially increased the average daily thermal efficiency (ηth), around 22.01%, 26.71%, 39.57%, and 56.21%, respectively. The results confirmed that integrating the v-corrugated basin, internal reflecting mirror, FPSC still, and FPSC nanofluids within a combined seawater distillation system can significantly enhance the performance of the CSS unit. These different combinations effectively raised the basin water temperature (Tw) and ΔTw-gi, consequently improving the overall performance of the solar still unit.
... where n PV is the number of PV modules, S PV the module surface, GSI the Global Solar Irradiation, f PV the derating factor for secondary losses, η INV the inverter efficiency (as represented in Fig. 3) and η PV the conversion efficiency of a module, calculated according to Duffie et al. [39] as: ...
... (2) where η PV,STC is the conversion efficiency at standard test conditions (STC), γ is the temperature coefficient and T CELL is the actual operating cell temperature calculated according to [39] as: ...
The growing share of Renewable Energy Sources (RES) is rising the amount of curtailed energy to preserve grid security. With the aim of evaluating a complementary storage solution to electric batteries for both new and revamping RES power plants, this study investigates the performance of a Thermally Integrated Pumped Thermal Energy Storage (TI-PTES) system integrated with a Photovoltaic (PV) power plant aimed to enhance the energy self-sufficiency of small-scale users. The assessment is carried out for a case study characterized by a demand of electricity, heating and cooling that vary throughout the year. The studied PTES system is based on the integration of a High Temperature Heat Pump (HTHP), two Thermal Energy Storage (TES) sections and an Organic Rankine Cycle (ORC) power plant. Results show the influence of the main design parameters, such as PV size, HTHP size and TES capacities on the overall system performance, evaluated by means of the energy self-sufficiency, energy self-consumption, round-trip efficiency, Levelized Cost of Storage and the Grid Impact indicator, which quantifies the energy exchanges with the grid (feed-ins and withdrawals) to the overall user demand. The influence of seasonality on the energy performance indicators was studied as well. For the case study considered, the best combination of design parameters for the PV-PTES system is identified with reference to a PV plant whose yearly energy production equals the energy demand and for a 55 kWe High Temperature Heat Pump, a 10 kW ORC and a storage volume of 48 m3 for each of the two TES units. The PTES system is characterized by a LCOS of 0.72 $/kWh, a round-trip efficiency of 28.2 % and its integration offers several advantages over the use of a PV plant without any storage section. In particular, the PTES unit leads to a substantial increase in the self-sufficiency, within the range 1–14 %, and a considerable decrease of the grid impact indicator, within the range 2–28 %.
... T sky = 0.0552.T 1.5 am (A.6) h con ab−w is the convective heat transfer coefficient between the absorber and water; is given as follows (Jhon and William 1991;Sahlaoui et al. 2020): ...
... (ii) For turbulent flow regime (Re > 2300) (Gnielinski 2013): The factor ζ is defined by: ζ = 1.8 × Log 10 (Re) − 1.5 (A.12) h ins−am is the overall heat transfer coefficient between the insulating layer and the ambient; is given by the following formula: (A.14) where σ and ε ins are Stefan−Boltzamnn constant and the insulating layer emissivity, respectively. h con ins−am is the convective heat coefficient is given as follow, Jhon and William (1991): The value of δ is given by the following formula: ...
This work aims to demonstrate the feasibility of solar heating of a stand-alone house located in a continental climate region in Algeria. The design and optimization of this system are based on dynamic simulations of a typical rural house using a TRNSYS-Fortran program. To manage all the subsystems composing the heating system, a pertinent control strategy is adopted. Using 2.8 m3 storage tanks, the optimal solar share in meeting the annual thermal needs of the house is 46%. Besides, an energy-efficient design based on a local bio-composite thermal insulation material reduces the thermal energy needs of the house by 42%. The results of optimization calculations are compared to experimental tests and show good agreement. For environmental impact, the study reveals that 39% of CO2 emissions can be avoided annually. Moreover, the economic cost of the system has been evaluated, and the results show that the payback period is 53 years.
... Burada, APV-T=0.54 m 2 PV-T'nin toplam alanıdır ve Ė metrekare başına PV-T'ye ulaşan güneş radyasyonudur ve aşağıdaki gibi bulunur [29]. ...
... Burada θ geliş açısıdır ve θ z PV-T için zenit açısıdır. Böylece, kuzey yarımküre için aşağıdaki gibi hesaplanır [29]: ...
... Due to the intermittency of solar energy, solar thermal energy systems need to be efficient and effective. Thermal energy can be stored in various forms: (i) sensible, (ii) latent or thermochemical [3]. Sensible heat storage involves increasing the temperature of the storage material without the material changing state, whereas latent heat storage involves increasing the temperature of the storage material to its change of state temperature [4]. ...
... Where is the mass of the sample in kg and the volume of water displaced by the sample in m 3 . The Fig. 1 shows the devices for measuring the density of the sample. ...
The use of solar energy is hampered by the intermittency of the resource and the constraints of storing the thermal form of this energy. The processes using this resource are therefore faced with problems of continuity of the process. To remedy this, this work proposes to develop a device for the accumulation of solar thermal energy by a sensitive storage system on a rock bed. A solar thermal energy storage system has been developed and experimentally studied with a view to coupling it to a solar dryer. The thermal performance of the system was evaluated in terms of temporal distribution of bed temperature, total energy stored, total energy discharged, charging efficiency, discharging efficiency. The results obtained indicate that the stratification in the storage system decreases in the afternoon due to the reduction of solar radiation and the output temperature of the solar collector. This contributes to a decrease in the thermal performance of the storage system. The charging efficiency obtained is 76.8%, the discharging efficiency 44.4%. The results also indicate that out of 4.7 MJ of total stored energy almost 89% or 4.17% was recovered during the discharge phase which is interesting for solar dryers.
... The hourly diffuse solar radiation is strongly correlated with the hourly clearness index K a as represented by Eq. (14) [40,41]: ...
... The hourly clearness index, given by Eq. (15), is the measure of air relative clarity. Less radiation is scattered when the air is pure [40,41]. ...
Spectral splitting technology can prevent a photovoltaic cell (PV) overheating ability and efficiency loss. The solar spectrum is split into two portions using this technology: the first produces electricity, while the second generates heat. The present research offers the design and performance evaluation of a novel PV-thermal (PV/T) system based on a compound parabolic concentrator (CPC) and a selective absorptive fluid-based optical filter. Different experiments are conducted to indicate the impact of 1, 3, and 5 cm air gaps between the optical filter and PV on the system's average outputs. In addition, the impact of tilting the solar concentrator on the system's performance was also investigated. Finally, a simulation of the cell's electrical performance was produced. Experimental findings demonstrated that all CPC-PV systems with an optical filter have a greater electrical efficiency of about 17% compared to 13.1% and 7.1% for no-filter CPC-PV systems and bare PV cells, respectively. The 3-cm air gap case also demonstrated the most significant electrical, thermal, and overall efficiency improvements , with average values of 17.1, 21.0, and 32.8%, respectively. Additionally, the inclined position of the CPC outperforms the horizontal position. Theoretical results, in terms of electrical performance, supported the experimental findings.
... Under steady-state conditions, the useful energy output is determined as the variance between the solar radiation incident on the absorber plate and the thermal losses ( > ) [30]. Now, the heat removal factor under steady-state conditions, as per the principles outlined in the Hottel-Whillier equation for usable heat gain [31,32], is expressed as follows: ...
The increasing concerns over fuel prices and global warming have propelled the engineering industry to explore innovative solutions for reducing greenhouse gas emissions and enhancing energy efficiency. Among these solutions, the Organic Rankine Cycle (ORC) has emerged as a promising technology for low to medium temperature waste heat recovery in industrial processes. ORC offers advantages such as low capital cost, small size, easy maintenance, and the ability to convert low-grade heat into electricity.
This paper delves into the significance of ORC in addressing environmental challenges and improving production efficiency. It highlights the growing attention towards low-temperature waste heat recovery and emphasizes the ORC's role in converting heat into usable electrical energy. The benefits of ORC span industrial waste heat recovery, harnessing renewable energies, and low-power heat generation, making it an economically viable and environmentally friendly solution.
The study includes simulation results using DWSIM simulation software, presenting data on heat flow at different pressures for various working fluids. The analysis offers insights into the variation of heat flow with pressure, optimal operating conditions, and the stability of heat flow for each fluid. Additionally, the paper discusses the potential applications of ORC in rural electrification and its contribution to the renewable energy mix.
Furthermore, the research explores the benefits of ORC in different industries, such as refrigeration and air conditioning, and provides data on overall efficiency under different conditions. The findings indicate the potential for ORC to be utilized in diverse settings, including solar thermal, biomass, and geothermal applications.
The study concludes with an examination of SORC (Sorption Organic Rankine Cycle) efficiency for different working fluids under varying turbine inlet conditions. The analysis reveals the influence of turbine inlet pressure and temperature on efficiency, offering valuable insights for the optimization of ORC systems.
... Furthermore flow in channels can also be linear or turbulent and for turbulent flow obstacles in the circular flow channel which will be more efficient. To improve solar water heaters thermal performance, many investigators proposed various strategies such as reducing the heat loss from the collector, creating of fluid turbulence pasting the heating surface, extending the heat-transfer are, increasing the absorptivity of absorber, and optimizing the design parameters such as various conduit cross area and absorber plate materials [7]. This paper theoretically and experimentally investigates the collector efficiencies of solar water heater with circular conduit cross sections. ...
The flow structure in a circular plate solar collector storage device, with circulation of the storage water inside circular pipe is studied experimentally using a constructed solar collector. Substantial circular plate solar collector efficiency improvement has been obtained employing circular flow conduits and using obstacles inside flow channel for making turbulence. Eventually solar radiation, solar absorption, stimulation of absorption which pertains with absorber material (copper), making of greenhouse effect by glass cover and black coating having maximum absorption and minimum reflectivity (around vantablack), making of turbulent flow, minimization of heat loss etc. influence the collector efficiency, and energy consumption are discussed. At length overview of this paper demonstrates overall thinking about design, cost, efficiency, and economical aspects. After completion of the apparatus through modification and experimentation it achieved the maximum thermal efficiency of 49.75%.
... where n PV is the number of PV modules, S PV the module surface, GI the Global Solar Irradiation, f PV the derating factor for secondary losses, η INV the inverter efficiency (as represented in Fig. 6 [31]) and η PV the module conversion efficiency. The module conversion efficiency and the cell temperature are calculated according to Duffie et al. [32]: ...
Globally, the increasing share of renewables, prominently driven by intermittent sources such as solar and wind power, poses significant challenges to the reliability of current electrical infrastructures, leading to the adoption of extreme measures such as generation curtailment to preserve grid security. Within this framework, it is essential to develop energy storage systems that contribute to reinforce the flexibility and security of power grids while simultaneously reducing the share of generation curtailment. Therefore, this study investigates the performance of an integrated photovoltaic-hydrogen fuelled-compressed air energy storage system, whose configuration is specifically conceived to enable the connection of additional intermittent sources in already saturated grids. The yearly and seasonal performance of the integrated energy storage system, specifically designed to supply flexibility services, are evaluated for a scenario represented by a real grid with high-variable renewables penetration and frequent dispatchability issues. Results show that the integrated system, with performance-optimized components and a new energy management strategy, minimizes photovoltaic energy curtailment, otherwise around 50%, to as low as 4% per year, achieving system efficiencies of up to 62%, and reinforces the grid by supplying inertial power for up to 20% of nighttime hours. In conclusion, the integrated plant, operating with zero emissions, on-site hydrogen production, and optimized for non-dispatchable photovoltaic energy utilization, proves to be effective in integrating new variable renewable sources and reinforcing saturated grids, particularly during spring and summer.
... represent the gas inlet and outlet temperatures in the parabolic solar collector, and -. and ̇. / are the heat capacity and mass flow rate of the gas, respecFvely. Under steady-state condiFons, the useful energy output is determined as the variance between the solar radiaFon incident on the absorber plate and the thermal losses ( < ) [30]. Now, the heat removal factor under steady-state condiFons, as per the principles outlined in the HoQel-Whillier equaFon for usable heat gain [31,32], is expressed as follows: ...
just to get feedback and if any correction needed then please reply me
... Kolektörün ısısal veriminin saptanmasına ilişkin olarak da şu yöntem izlenmiştir: Güneş kolektörleri yaklaşık olarak sabit koşullar altında çalışmaktadırlar. Bu koşullar altında ısısal verimleri, kolektör yüzeyine gelen güneş radyasyonundan optik ve termal kayıpların çıkarılarak elde edilen yararlı enerjinin yüzeye gelen toplam enerjiye oranlanması ile elde edilmektedir [9][10][11]. ...
Making use of solar energy is one of the ways that hot water is obtained nowadays. Because of its position in the sun belt, Turkey is well-positioned to utilize this limitless energy. Research into producing novel and inventive designs for collectors in order to boost collector efficiency ought to proceed quickly because of global warming. In this experimental investigation; a tube-flat plate closed system type solar water collector that is constructed from 304 chromium material and appropriate for Turkey meteorological conditions has been designed and manufactured. This solar collector has also been tested according to EN (European Union Norms) 12975-2 (2003) for its thermal efficiency. This collector can be worked as a closed system with help of working fluid; it is never freeze during cold weathers; it can be used during all seasons and can be directly connected to the pressurized city water line system; it is not to give any negative effects on chemical compositions of the water; it is not to be needed any maintenance during lifetime and it have less price, more lifetime, high thermal efficiency, easier assembling and manufacturing when compared with aluminum and copper type collectors. As a result of the work, it was seen that the average end use thermal efficiency of this collector is 49.50%.
... The thermal energy gain (Q u ) is calculated by considering the total heat losses (top, bottom, and sidewall losses) which are determined by using mathematical expressions. 49,50 Furthermore, the net energy gain (Q net ) is calculated using thermal energy gain (Q u ) and the equivalent pumping power required by the blower (P m /C). The following expression are used to compute the net energy gain. ...
The thermohydraulic performance (THP) of a solar air heater (SAH) duct with staggered D‐shaped ribs as roughness geometry is examined in this work using three‐dimensional numerical investigation. The investigation is carried out at roughness parameters of radius of rib to transverse pitch (r/Ptv) ratios of 0.1–0.35 and longitudinal pitch to radius of rib (Plg/r) ratios of 4–10 under varied operating circumstances of Reynolds number (Re) from 10,200 to 20,200. The maximum Nusselt number (Nu) is obtained to be 81.3 at Re of 20,200, r/Ptv as 0.1, and Plg/r as 4. In contrast, the maximum friction factor (f) is obtained to be 0.0169 at Re of 10,200, r/Ptv as 0.35, and Plg/r as 4. In the range of parameters examined, the maximum enhancement in Nusselt number (Nu/Nus) is observed to be 1.35 at an optimal parameter of r/Ptv as 0.1, Plg/r as 4, and Re as 10,200. Correspondingly, the enhancement in the friction factor (f/fs) at this optimum parameter is 1.87. The maximum value of the THP parameter is found to be 1.1 at the same optimum range of parameters. In further analysis, correlations were developed for Nusselt number (Nu) and friction factor (f) in terms of r/Ptv, Plg/r, and Re with a deviation of ±2% and ±1.5%, respectively.
... The correction factor F R is the heat removal factor and is defined as the ratio of the actual useful energy to the useful gain in case the whole collector area is at the temperature of the inlet fluid. It is calculated in the current model as described in [24]. ...
... The thermal efficiency (η th ) of a solar collector can be defined as the ratio between the actual useful energy gained by the heat transfer fluid, typically water (Q U ), and the incident solar radiation on the absorber of the solar collector. This can be mathematically expressed by equation (5) [62][63][64]. ...
Flat plate solar collector (FPSC) and parabolic trough solar collector (PTSC) are widely used for residential solar water heating (SWH) applications. This work studied two different solar collector systems. Nanofluid and its influence on the residential solar water heating (SWH) systems were investigated. The two SWH systems were designed, installed, tested, and compared at varying mass flow rates (mf) of 0.47, 1.05, and 1.75 kg min−1 in ambient environmental conditions. The comparative study was conducted according to thermal efficiency (ηth), useful energy gain (QU), stored energy (QS), outlet hot water temperature (To), and difference temperature (ΔT) between the cold inlet and hot outlet water from the collectors. The analysis of outcomes showed that the PTSC was more efficient than FPSC. The FPSC and PTSC systems performance were investigated using two different types of nanofluids. Carbon nanotubes in water and ethylene glycol were utilized. A remarkable improvement in the average thermal efficiency 64.1 % and 80.6 % of FPSC and PTSC systems using ethylene glycol nanofluid were obtained respectively. The total reduction in CO2 emissions was 31.26 kg/day and 39.28 kg/day for the FPSCs and PTSCs, respectively in the presence of ethylene glycol nanofluid. A significant saving in CO2 release is owing to the renewable clean energy of solar collectors.
... Since the solar position has a great impact on the radiative cooling power of the non-horizontal surface, the average radiative cooling power of the whole day is used to evaluate the radiative cooling capacity at various angles. Therefore, the time-dependent solar radiation model should be established to calculate the radiative cooling power during the day and the specific steps are as follows [30]. ...
... The only plant with a solar concentrator currently installed in Brazil is a demonstration plant and is of the parabolic cylinder type, installed in the CEFET-MG laboratory (Neto et al., 2019). with tracking systems there is the cylinder-parabolic collector, Fresnel, parabolic disk and Scheffler (DUFFIE and BECKMAN, 2013). All the collectors mentioned, except for the flat collector and evacuated tube, are concentrators, i.e., they have an opening area larger than the area of reception (absorption) of radiation, thus achieving high temperatures in the receiver. ...
The interest in exploiting solar energy has been steadily increasing as the world is aiming at sustainability. This work focused on making better use of solar energy through the manufacturing of a low-cost mechanism for solar tracking, with both horizontal and vertical rotating axes, to be coupled to a parabolic solar concentrator. For the electronic parts, it was employed a microcontroller Arduino UNO, power window regulator motors, a photoresistor sensor, a IBT-2 H-bridge, and a micro switch. On the other hand, the mechanical parts of the solar tracking system were fabricated using a 3D printer. Besides, this project introduced new concepts regarding the mechanical parts, which are not discussed in the literature of solar tracking systems, such as radial and straight oblong holes as well as the axial increase in the height of the motors. As a final result, we obtained an optimized setup for a parabolic solar concentrator equipped with a solar tracking system useful for water heating, which combines better efficiency in energy conversion with an affordable cost for needy people.
... The power production of the PV system was simulated as suggested by Duffie et al. [38] by means of the following equation: ...
The integration of an increasing share of Renewable Energy Sources (RES) requires the availability of suitable energy storage systems to improve the grid flexibility and Compressed Air Energy Storage (CAES) systems could be a promising option. In this study, a CO 2-free Diabatic CAES system is proposed and analyzed. The plant configuration is derived from a down-scaled version of the McIntosh Diabatic CAES plant, where the natural gas is replaced with green hydrogen, produced on site by a Proton Exchange Membrane electrolyzer powered by a photovoltaic power plant. In this study, the components of the hydrogen production system are sized to maximize the self-consumption share of PV energy generation and the effect of the design parameters on the H 2-CAES plant performance are analyzed on a yearly basis. Moreover, a comparison between the use of natural gas and hydrogen in terms of energy consumption and CO2 emissions is discussed. The results show that the proposed hydrogen fueled CAES can effectively match the generation profile and the yearly production of the natural gas fueled plant by using all the PV energy production, while producing zero CO2 emissions.
... The energy production of the PV system was simulated as suggested by Duffie et al. [34], considering solar panels inclined at 30° from the horizontal plane (tilt=30°) and oriented towards the south (azimuth=0°). Typical weather conditions provided by Meteonorm software [35] for a latitude of 39.21° were considered. ...
The integration of the increasing share of Renewable Energy Sources (RES) requires the availability of suitable energy storage systems to improve the grid flexibility, and Compressed Air Energy Storage (CAES) systems could be a promising option. In this study, a CO2-free Diabatic CAES system is proposed and analysed. The plant configuration is derived from a down-scaled version of the McIntosh diabatic CAES plant, where the natural gas is replaced with green hydrogen, produced on site by a Proton Exchange Membrane electrolyser powered by a Photovoltaic power plant. In this study, the components of the hydrogen production system are sized to maximize the Self-Consumption share of PV energy generation and the effect of the design parameters on the H2-CAES plant performance are analysed on a yearly basis. Moreover, a comparison between the use of natural gas and hydrogen in terms of energy consumption and CO2 emissions is discussed. The results show that the proposed hydrogen fuelled CAES can effectively match the generation profile and the yearly production of the natural gas fuelled plant by using all the PV energy production, while producing zero CO2 emissions.
... The earliest and most extensively employed model presented for the computation of global solar radiation on a horizontal surface is that of Angstrom (Angstrom 1924). Other studies have calculated solar radiation, e.g., linear regression models such as the Angstrom-Prescott model and nonlinear models such as Duffie et al. (2013). In recent times, many research scholars have endeavored to enhance the performance of empirical methods and generate a machine learning-based approach to increase the precision of solar radiation estimates (Bellido-Jimenez et al. 2021;Venu et al. 2023). ...
Solar radiation estimation is essential with increasing energy demands for industrial and agricultural purposes to create a cleaner environment, negotiate climate change impacts, and attain sustainable development. However, the maintenance and operation of solar radiation measurements are costly due to the lack of pyranometers or their failure; hence, obtaining reliable solar radiation data is challenging in many subtropical regions. Despite its importance, a few studies use machine learning algorithms for solar radiation estimation in Bangladesh. To this end, this study contributes to filling the gap twofold. First, we presented the potentials of ensemble models, such as Bagging-REPT (reduced error pruning tree), random forest (RF), and Bagging-RF, which were compared to three standalone models, namely, Gaussian process regression (GPR), artificial neural network (ANN), and support vector machine (SVM), for estimating daily global solar radiation in three Bangladeshi regions. Second, we explore the optimal input parameters influencing solar radiation change at the regional scale using a classification and regression tree (CART)-based feature selection tool. Satellite-derived ERA5 reanalysis and NASA POWER project datasets were used as input parameters. The performance of the models was compared using performance evaluation metrics like correlation coefficient (r), root mean square error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE), index of agreement (IA), and Taylor diagram. Results suggested that the RF model performed 5.47-37.22% better than the standalone models in estimating daily solar radiation at Chuadanga in terms of RMSE. Besides, the other ensemble model Bagging-RF showed 14.9-25.03% and 11.46-30.97% greater performances in Dinajpur and Satkhira than the conventional models in RMSE metric. Besides, this study may provide knowledge to the policymakers to make critical judgments on future energy yield, efficiency, productivity, and operation, which are essential elements for investments and solar energy conversion applications in the subtropical areas of the world.
... Surely, the number of studies that explicitly followed LCC or LCA guidelines is very limited (only 7), and almost exclusively concerns the LCC integrated with LCA/S-LCA. In particular, five studies -Bekel and Pauliuk (2019) (Duffie et al. 1994), but this is a procedure not a standard. ...
Purpose
The aim of this research is to carry out a literature review on the use of life-cycle cost (LCC) approaches for hydrogen technologies, by analysing its evolution over a decade (2012–2021).
Methods
The SCOPUS database has been used to select relevant literature on the subject. After adoption of inclusion/exclusion criteria, a total of 67 papers were selected for our review. Then, we analysed these studies in terms of hydrogen technologies (fuel cells, electrolysers, hydrogen storage approach, etc.) covered by the LCC approaches. In addition, we also performed an analysis of the LCC features — type of LCC (conventional, environmental, social), integration with LCA/S-LCA, guidelines followed, system boundaries (cradle-to-farm gate, cradle-to-consumer, cradle-to-grave, cradle-to-cradle), functional units, financial tools (NPV, BEP, etc.), type of costs included, and life span — to provide a comprehensive view of LCC studies applied to hydrogen technologies. We also discussed and interpreted the most significant findings.
Results and discussion
Our main results can be summarised as follows: (i) the number of LCC studies for application to hydrogen technologies has increased in the decade 2012–2021; (ii) China is the leading country for number of publications on the subject (15 papers), even if the most prolific author and institution are Iranians; (iii) a large number of studies performed LCC analysis including fuel cells and/or electrolysers based on proton exchange membranes; (iv) the most widely used LCC approach is a cradle-to-consumer (37 papers); (vi) almost all the studies on LCC of hydrogen technologies included initial, operation and maintenance costs; while other costs — replacement, external, end-of-life — are included in a limited number of papers; (vii) the net present value (NPV) is the most used financial tool.
Conclusions
LCC analysis for application to hydrogen technologies has gained interest in recent years. However, the number of studies that explicitly follow LCC or LCA guidelines is very limited (only 7). The life-cycle cost analyses performed are quite incomplete in terms of costs included in the life-cycle stages. Besides, there is a lack of information and uniformity in the use of functional units and financial tools.
... O modelo matemático proposto neste trabalho para a avaliação do desempenho térmico e elétrico de um PV/T é baseado no modelo de coletor solar plano tipo tubo-aleta, descrito por Duffie and Beckman (2006), com as devidas modificações para a inclusão do módulo fotovoltaico, e também embasado no trabalho de Ferreira et al. (2014), onde as equações para modelo matemático propostas são explicitadas e foram adaptadas ao modelo para realização de simulações computacionais através do software Engineering Equation Solver (EES) disponibilizado pelo Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG). Na : Condutividade obtida da média da condutividade da camada de EVA, Tedlar abaixo das células FV e da cola utilizada para unir o módulo FV e as aletas do coletor solar térmico (W/m K); ...
Aproximadamente 15% da radiação solar incidente em módulos fotovoltaicos (FV) poli-cristalinos são convertidos em energia elétrica, o restante ou é refletida ou é transformada em calor. Como consequência, os painéis são aquecidos, ocasionando redução em sua eficiência elétrica, que é proporcional ao aumento de temperatura, e possível degradação física de suas células fotovoltaicas ao longo dos anos. Portanto, a elevação da temperatura de operação das células é um efeito indesejado, porém, inevitável, que pode ser reduzido com a integração dos módulos FV à uma placa absorvedora como às utilizadas em coletores solares planos que irão permitir a cogeração de calor e eletricidade, preservando a integridade física das células fotovoltaicas a partir da mesma área coletora. Dessa forma, esse trabalho propõe um modelo matemático para prever o comportamento / desempenho térmico e elétrico de um módulo fotovoltaico acoplado a um coletor solar plano (Photovoltaic Thermal Hibrid Solar Collector – PV/T, em inglês) em regime permanente a partir da variação da radiação solar incidente e da velocidade do vento.
... Finally, the total incident radiation has been calculated based on the HDKR model. A detailed description of the conversion process is available at Duffie and Beckman [53]. ...
It remains a significant technical and economic challenge to fully power large-scale grids with intermittent renewable energy (RE). Meanwhile, due to the rapid decrease in the cost of RE power generation technologies in recent years, the number of real-world implementations and studies dedicated to the optimal capacity sizing of renewable off-grid systems has increased. However, a common approach in the literature is to rely on typical single-year meteorological and demand data. A negative effect of this assumption is that it does not consider the RE inter-annual variability, which might cause blackouts or oversizing the system and large curtailments. This study employs 43 years of hourly solar, wind, and demand data, coupled with different microgrid configurations, to evaluate the impact of diverse simulation periods on the total system cost, optimal RE mix, and system reliability. Our findings indicate that extended simulation periods considerably increased renewable energy systems (RES) reliability and that the resulting configurations can be up to 94% more robust than those obtained using a single year of data. Additionally, the optimal energy storage requirements increased when considering longer simulation periods, indicating that short simulation periods could underestimate energy storage capacities in off-grid systems. The overestimations or underestimations resulting from optimizations based on single-year data directly affect the long-term sustainability, reliability, and cost-effectiveness of the RES.
... Various models concentrate on the thermal characteristics of the PV modules in addition to these electrical equivalent models. While some models are based on thermal capacitance [19], others are based on the total heat loss coefficient [20,19]. However, as the manufacturers do not offer adequate details about these features, these models are not realistic to use. ...
Due to the growing demand, assessing performance has become obligatory for photovoltaic (PV) energy harvesting systems. Performance assessment involves estimating different PV system parameters. Traditional ways, such as calculating solar radiation using satellite data and the IV characteristics approach as assessment methods, are no longer reliable enough to provide a reasonable projection of PV system parameters. Estimating system parameters using machine learning (ML) approaches has become a reliable and popular method because of its speed and accuracy. This paper systematically reviewed ML-based PV parameter estimation studies published in the last three years (2020 – 2022). Studies were analyzed using several criteria, including ML algorithm, outcome, experimental setup, sample data size, and error metric. The analysis revealed several interesting factors. The neural network was the most popular ML method (32.55%), followed by random vector functional link (13.95%) and support vector machine (9.30%). Dataset was sourced from hardware tests and computer-based simulations: 66% of the studies used data from only computer simulation, 18% used data from only hardware setup, and the 16% experiments used data from both hardware and simulations to evaluate different system parameters. The top three most commonly used error metrics were root mean square error (29.1%), mean absolute error (17.5%), and coefficient of determination (15.9%). Our systematic review will help researchers assess ML algorithms' projection in PV system parameters estimation. Consequently, scopes shall be created to establish more robust governmental frameworks, expand private financing in the PV industry, and optimize PV system parameters.
... The proposed unsteady model was not robust to provide a better convergence near the true data. The different modelling tools such as Engineering Equation solver (EES), WATSUN, Polysun and TRNSYS were used along with porous media to simulate a similar environment for the solar thermal system [15,16]. However, the application of different software may have little or no effect on the stability of a given model unless the proposed algorithm is robust in itself to tackle the given problem. ...
The focus of this work is on developing a nonlinear grey model for the laminar flow regime of carrier fluid across the flat plate collector. The trust region reflective algorithm was used to solve the nonlinear laminar flow problem and handle the sparse matrix. The stream function, dimensionless velocity, gradients of velocity components, carrier fluid temperature, and the absorber plate temperature were estimated for a flat plate collector operated with and without a circular chimney. Similarly, the same technique was adopted to determine a model for heat transfer across the absorber plate. The numerically obtained solution was also compared with the parameters obtained through the instrumental measurement. The relative tolerance was kept at 10−5 for the white and grey box solutions. The developed model was noticed to have a smaller deviation than the conventional analytical model to predict the experimental values. The slip condition was observed for the proposed scheme. The uncertainty in the temperature measurement through the proposed model varies from ±0.53 to ±1.47 K. The minimum absolute percentage error (MAPE) lies in the domain of 0.52–1.67% for the nonlinear grey model, whereas the linear grey model for measuring absorber plate temperature has a percentage error of 0.0011–0.02%.
The use of electricity to heat bath water is still quite common in Brazil, especially in the South and Southeast regions. This practice represents about 24% of the total energy consumption in the residential sector. Additionally, its usage is concentrated between 6 and 9 PM, leading to serious issues in energy generation and distribution during this interval. Given the importance of rationalizing the electricity consumption, the aim of this paper was to conduct a technical-economic analysis for the implementation of a hybrid solar heating system to supply the demand for hot water in the bathrooms of a poultry slaughterhouse located in the Western region of Paraná. For this, different scenarios of usage were developed, where the type of solar collector and the auxiliary power source were varied and a comparison between the alternatives and the conventional water heating systems was made. A calculation routine based on the F-Chart method was used to size the alternative systems. The Net Present Value (NPV), the Internal Rate of Return (IRR) and the discounted Payback were used as decision-making criteria. All configurations sized in this study were proved to be viable. However, the most interesting one, from a technical-economic point of view, was the combination of the flat-plate solar collectors and the electric auxiliary power source. The comparison of this scenario with the conventional source showed an NPV of R$ 92,916.84, an IRR of 59.9%, and a payback period of 1 year and 11 months.
В роботі запропонована модель автономної фотоелектричної системи з широтно-імпульсним контролером заряду акумуляторної батареї. Для побудови моделі використано програмне середовище Matlab/Simulink. Описано основні блоки, структуру та особливості побудови моделі, а також продемонстровано її можливості. Проведено моделювання поведінки автономної фотоелектричної системи при зміні основних зовнішніх факторів, таких як потік енергії сонячного випромінювання та температура фотоелектричного модуля. Проаналізовано процеси, що відбуваються в системі під впливом зміни цих факторів, з’ясовано їх вплив на параметри окремих компонентів. Показано, що при збільшенні температури модуля та зменшенні потоку сонячної радіації напруга модуля наближається до напруги акумуляторної батареї, наслідком чого є підвищення ефективності широтно-імпульсного контролера заряду, що корелює з описаними в літературних джерелах результатами. Продемонстровано можливість застосування розробленої моделі для дослідження роботи реальних автономних фотоелектричних систем в заданих кліматичних умовах. Здійснено моделювання роботи переносної автономної фотоелектричної станції «Турист-80 компакт» в кліматичних умовах Херсонської області протягом типової доби липня. На основі аналізу енергетичних показників, отриманих за результатами моделювання, встановлено, що дана автономна станція за добу здатна забезпечити споживання електричної енергії в обсязі 545 Вт год за умови допустимого розряджання акумуляторної батареї на 50%, а у випадку повного відновлення заряду акумуляторної батареї на кінець світлового дня споживання має бути зменшене до 305 Вт год, що є достатнім для 3 циклів заряджань мобільних телефонів, однієї години роботи портативного світлодіодного світильника та використання переносного автомобільного холодильника протягом 5,5 годин.
Wastewater treatment plants (WWTPs) consume significant amount of energy to sustain their operation. From this point, the current study aims to enhance the capacity of these facilities to meet their energy needs by integrating renewable energy sources. The study focused on the investigation of two primary solar energy systems in As Samra WWTP in Jordan. The first system combines parabolic trough collectors (PTCs) with thermal energy storage (TES). This system primarily serves to fulfill the thermal energy demands of the plant by reducing the demands from boiler units, which allows more biogas for electricity generation. The second system is a photovoltaic (PV) system with Lithium-Ion batteries, which directly produces electricity that will be used to cover part of the electrical energy demands of plant. To assess the optimal configuration, two distinct scenarios have been formulated and compared to the current base scenario (SC#1). The first scenario (SC#2) focuses on maximizing the net present value (NPV) and minimizing the levelized cost of electricity (LCOE). The second scenario (SC#3) is centred on minimizing the levelized cost of heat (LCOH). The findings indicate that both scenarios succeeded in reducing the reliance on the grid to a value that reach 1 %. Moreover, they both reduced biogas percentage in energy production from 88 % to approximately 65 % through the integration of the PV system. In terms of thermal demand, SC#2 reduced the reliance on biogas boiler units from 100 % to 25 %, while SC#3 achieved an even more impressive reduction to just 8 %. The best LCOE value was attained in SC#2, at 0.0895 USD/kWh, with an NPV of 10.54 million USD. Conversely, SC# 3 yielded an LCOH value of 0.0432 USD/kWhth compared to 0.0534 USD/kWhth USD for SC#2. Despite their relatively high capital and operating costs, SC#2 and SC#3 managed to substantially decrease the annual electricity expenditure from approximately 2 million USD to 86,000 USD and 0 USD, respectively.
In this work is established a parametric identification method for an absorption air conditioning solar plant. A scaled thermal plant, consisting of a thermal capacitor and a flow line that acts as a capacitor and thermal energy radiator is used. As the mathematical model of the scaled plant is structurally identical to that of the solar plant the first is used to determine the methodology that can be used later for the identification of the PTC solar plant. Parametric identification is a necessary step that allows to determine the unknown parameters of the mathematical model of any solar/thermal plant. This model then can be used to analyze the plant characteristics and design an appropriate control algorithm. Although the system model is nonlin-ear it can be expressed in the form of a linear regressor in the parameters. This permits to use the least squares method as the identification method. The method is applied to the thermal plant to identify the useful form that the covariance matrix and excitation signals should have to ensure that when applied to the solar plant its unknown parameters can be properly estimated. Once the solar plant parameters are properly estimated model can be used to analyze and simulate the operation of the ab-sorption air conditioning system.
In this study, we introduce an innovative polygeneration system that combines solar and biomass energies to generate power, heating, hot air for the drying process, oxygen, and ammonia. The proposed polygeneration system comprises a solar tower subsystem (STS) integrated with two energy storage tanks (cold and hot), a gas turbine cycle (GTC), an organic Rankine cycle (ORC), a proton exchange membrane (PEM) electrolyzer, a thermoelectric generator (TEG), a cryogenic air separation unit (CASU), and an ammonia synthesis reactor (ASR). The GTC and the ORC equipped with the TEG are utilized for power production. The steam for the gasification process, hot air for the drying process and heating are produced by three regenerators. The PEM electrolyzer is used for the decomposition of water into hydrogen and oxygen, while the air separator (cryogenic method) is employed for the separation of air into nitrogen and oxygen. The separated oxygen is stored in an oxygen tank, while nitrogen and hydrogen are utilized for the ammonia generation. The system is evaluated from energy, exergy, economic and, environmental standpoints. Based on the findings, the proposed system is capable of generating approximately 163 MW of net power, 150 MW of heating, 100 MW of drying, 21.7 kmol/hr of oxygen and 23.24 kg/hr of ammonia. The total energy and exergy efficiencies, as well as the life cycle cost (LCC) and CO2 emissions are determined to be 70.68 %, 48.71 %, 1.175×109 $ and 381.3 kg/MWh, respectively. Additionally, a multi-objective Grey Wolf optimization algorithm is utilized to optimize the exergy efficiency, LCC, and CO2 emissions. The optimized results yield an exergy efficiency of 51.02%, an LCC of 1.16×109 $, and a CO2 emissions of 359.73 kg/MWh. The proposed system demonstrates encouraging thermodynamic and economic performances, providing an appealing solution for efficient utilization of abundant solar and biomass resources.
The PVF-Chart method consists of a combination of correlations and fundamental expressions for the hourly calculations of solar radiation at a given location. It uses long-term monthly average solar radiation and ambient temperature to predict the annual performance of a photovoltaic array. the present document aims to analyse the long-term performances of a PV system used to cover an individual household situated in different Algerian climatic zones. The obtained results are compared to those presented in the literature and from which it can be concluded that the developed software program permits to calculate the PV system performances with a good exactitude which confirm its uses as a tool to analyse the long-term performance of PV system at any climate in where only the monthly mean daily weather data are available. From these later, the hourly, the daily and the annual performance of a photovoltaic array are predicted. For the preliminary assessment of the energy-producing of the studied PV project, the LCOE was calculated for three interest rates and two lifetimes.
More effective use of solar energy in hot water systems is made possible by optimising heat transfer and flow resistance. In light of this, Research has been conducted to enhance convective heat transfer while analysing flow friction characteristics for best performance, resulting in the design of novel inserts known as customised twists, which increase the efficiency of the solar hot water system. A conventional, plain tube heater is used as a baseline for the study on thermal characteristics, heat transportation and flow friction attributes. A thorough analysis and comparison of the thermal behaviour of the system with customised twist inserts that have been modified using rods and spacers of different lengths is performed. As a result of the induced disturbance in the fluid particle flow pattern throughout the length of risers, a significant improvement in the coefficient of convective heat transfer is observed. The study validated the correlations for the convective heat transfer coefficient and the resistance coefficient against previous research findings. The findings indicated that the thermal efficiency of the full-length twist-inserted system is almost three times greater than that of a plain collector while doubling its pressure drop. The findings of this research could be useful in designing low-cost, compact solar water heaters.
Description
Recent advances in polymer chemistry and stabilization and increasing consumer demands for longer lasting products require use of faster, more reliable methods to evaluate durability of materials. The controversy continues: How to properly test materials for resistance to sunlight, rain, and atmospheric acid and salt? Proper use of results from accelerated tests depends on understanding: 1) how the exposure stresses in the accelerated test match those found in field use and 2) impact of variability in results from accelerated tests and outdoor exposures. STP 1202 presents 15 peer-reviewed papers that cover research in characterization of exposure tests, and new developments in exposure equipment and exposure test design.
In this research paper, a solar air heater with triangular fins has been experimentally analysed and optimized. Initially, an experimental set-up of a solar air heater having triangular fins has been developed at the location of 28.10°N, 78.23°E. The heat transfer rate through fins and fins efficiency has been determined by the Finite Difference Method model equations. The experimental data and modeled data of response parameters have been optimized in MINITAB-17 software by the Response Surface Methodology tool. For creating the response surface design, three input parameters have been selected namely solar intensity, Reynolds number, and fin base-to-height ratio. The range of solar intensity, Reynolds number, and fin base-to-height ratio is 600 to 1000 W/m2, 4000 to 6000, and 0.4 to 0.8 respectively. The response surface design has been analyzed by calculating the outlet temperature, friction factor, Nusselt number, fin efficiency, thermal performance factor, and exergy efficiency. The optimum settings of input parameters: solar intensity is 1000 W/m2; Reynolds number is 4969.7, and the fin base to height ratio is 0.6060, on which these response: namely outlet temperature of 92.531°C, friction factor of 0.2350, Nusselt number of 127.761, thermal efficiency of 50.836%, thermal performance factor of 1.4947, and exergy efficiency of 8.762%.
For organometallic halide solar cells (OHSC), it is expected that their performance in hot climates is to be challenged by high operating temperature conditions typical of these regions. This study explores, for the first time, the performance of formamidinium tin iodide (FASnI3) solar cells under variations of seasonal and climatic conditions in Nigeria using a non-steady state thermal model. From the thermal analysis, results show that the air temperature in the location of the solar cell under study played a significant role in the increase and decrease of the rate of the overall heat transfer coefficient of the OHSC. However, the cell temperature depended on the rate of heat loss and the solar radiation absorbed by the OHSC. The electrical analysis was based on the numerical simulation of a FASnI3 solar cell with the aid of a Solar Cell Capacitance Simulator (SCAPS). A decrease in the power conversion efficiency (PCE) as the cell temperature increased was observed. Overall, while the OHSC suffered losses in efficiency in all locations during the hot season, the wet season saw an improvement in the PCE, especially in Twon-Brass (0.5 % increase) where the most heat loss and least insolation were recorded. This shows that the power conversion efficiency of an operating OHSC is temperature-dependent, rather than the abundance of solar irradiance.
Cityscapes provide a complex environment, where solar radiation is unevenly distributed, especially since urban features started to propagate more and more vertically. Due to the dynamic overshadowing effects present on building surfaces, quantifying these phenomena is essential for predicting reductions in solar radiation availability that can significantly affect potential for solar energy use. Numerical radiation algorithms coupled with GIS tools are a pathway to evaluate those complex effects. Accurate representation of the terrain, vegetation canopy and building structures allows better estimation of shadow patterns. Higher spatial and temporal resolutions deliver more detailed results, but models must compromise between accuracy and computation time. In this paper, models ranging from simple 2D visualization and solar constant methods, to more sophisticated 3D representation and analysis, are reviewed. Web-based solar maps, which rely on the previous features to successfully communicate the benefits of the solar resource to the public and support in the policy-making process, are also addressed.
Se diseñó un secador solar de tiro forzado, para el secado de productos agrícolas. Se realizaron pruebas en condiciones climáticas donde la temperatura ambiente promediaba los 28 grados centígrados y la humedad relativa era del 52%. El colector solar consta de dos placas una absorbedora (que está expuesta directamente al sol a través de los cristales), y otra que constituye el techo de la cámara de secado, ambas forman un túnel en el cual se coloca un ventilador para forzar el aire a través de éstas, además de una cámara de secado.
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