scholarly journals Experimental Investigation on Evaluation of Thermal Performance of Solar Heating System Using Al2O3 Nanofluid

2020 ◽  
Vol 10 (16) ◽  
pp. 5521 ◽  
Author(s):  
Youngho Lee ◽  
Hyomin Jeong ◽  
Ji-Tae Park ◽  
Antonio Delgado ◽  
Sedong Kim

Over the years, solar collecting systems have gained interest in renewable energy. This study investigated improving the efficiency of the working fluid in thermal solar systems by using nanofluids with three concentrations of alumina, 0.1, 0.3, and 0.5 wt%. The UV-vis absorbance, electronic conductivity, and thermal transfer properties of the nanofluids were analyzed, and the thermal changes with exposure to solar radiation in an experimental collector system were measured by pyranometer. The electronic conductivity, thermal conductivity, and UV-vis absorbance increased with the alumina concentration. Moreover, the temperatures of the nanofluids increased more under solar irradiation than that of distilled water. This implies that the alumina nanofluids absorb solar energy more efficiently than water. The findings of this study suggest that the use of both alumina nanofluids and nanoparticles will improve the efficiency of thermal solar power systems.

Author(s):  
Masahiro Taniguchi ◽  
Shigeki Hirasawa ◽  
Shunsaku Nakauchi ◽  
Tadayoshi Tanaka

An evacuated solar collector system with flow boiling in tube has high collector efficiency of solar energy. In this paper, we present experimental and simulation results for characterizing an evacuated flat plate solar collector. By comparing the experiment results with six boiling heat transfer correlation equations, we found that Sani’s correlation is closest to our experimental results. Subsequently, this paper reports on how various factors impact collector efficiency. Collector efficiency decreases with decreasing flow rate of the working fluid, with decreasing solar irradiation, with reduction of thickness and thermal conductivity of the heat collector plate. Collector efficiency increases with decreasing saturation temperature of the working fluid, with decreasing vacuum pressure in the collector, with small bending angle of the heat collector tube. Collector efficiency does not change with change of inside diameter of the heat collection tube, and with change of inlet subcooling temperature of the working fluid.


2021 ◽  
Vol 39 (1A) ◽  
pp. 137-152
Author(s):  
Hosham S. Anead ◽  
Khalid F. Sultan ◽  
Sura Abedul Jabbar

This research revealed control on nanofluid temperature in the evacuated tube solar collector system, where nanofluid used in ETSC as working fluid to increase heating system thermal efficiency. Smart curtain was used to shadow the evacuated tube solar collector in heating or cooling conditions to control the temperature of the nanofluid. Moreover, (PSO based PID) controller which is an artificial intelligence method was ‎applied to control on the shadow the evacuated tube solar collector. Where the curtain's main idea is to control the polarization of the sun's radiation, the work of the curtain refers to the parameters: the first parameter is the nano fluid temperature and the second is the ambient temperature, and one output parameter is defined by (distance parameter).


2013 ◽  
Vol 2013 ◽  
pp. 1-6
Author(s):  
Meng-Hui Wang

Due to the complex parameters of a solar power system, the designer not only must think about the load demand but also needs to consider the price, weight, and annual power generating capacity (APGC) and maximum power of the solar system. It is an important task to find the optimal solar power system with many parameters. Therefore, this paper presents a novel decision-making method based on the extension theory; we call it extension decision-making method (EDMM). Using the EDMM can make it quick to select the optimal solar power system. The paper proposed this method not only to provide a useful estimated tool for the solar system engineers but also to supply the important reference with the installation of solar systems to the consumer.


2014 ◽  
Vol 60 (4) ◽  
pp. 315-320 ◽  
Author(s):  
Gustaw Mazurek

Abstract Estimation of Global Tilted Irradiation (GTI) is a key to performance assessment of typical solar systems since they usually employ tilted photovoltaic (PV) modules or collectors. Numerous solar radiation databases can deliver irradiation values both on horizontal and tilted plane, however they are validated mostly with horizontal-plane ground measurements. In this paper we have compared GTI estimates retrieved from five Internet databases with results of measurements at two PV systems located in Poland. Our work shows that in spite of good agreement in annual scale, there is a tendency to underestimate GTI in summer and overestimate in winter, when PV modules can receive less than a half of expected irradiation. The latter issue affects sizing of PV system components and implies a correction needed to achieve all-year long operation.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Chong Li

The objective of this paper is to establish the performance of 8 kWp grid-connected photovoltaic (PV) power systems based on different PV module technologies in Nanjing, China. Nanjing has a hot summer and a cold winter which are considered based on monthly average solar irradiation and ambient temperature specifically for the deployment of grid-connected PV systems. The study focuses on performance assessment of grid-connected PV systems using typical PV modules made of monocrystalline silicon (m-Si), polycrystalline silicon (p-Si), edge-defined film-fed growth silicon (EFG-Si), cadmium telluride (CdTe) thin film, copper indium selenide (CIS) thin film, heterojunction with intrinsic thin layer (HIT), and hydrogenated amorphous silicon single-junction (a-Si:H single-PV) installed on location. The yearly average energy output, PV module and system efficiency, array yield, final yield, reference yield, performance ratio, monthly average array capture losses, and system losses of seven PV module technologies are all analyzed. The results show that grid-connected PV power system performance depends on geographical location, PV module types, and climate conditions such as solar radiation and ambient temperature. In addition, based on energy output and efficiency, the HIT PV power technology can be considered as the best option and CdTe and p-Si as the least suitable options for this area. The monthly average performance ratio of the CdTe technology was higher than those of other technologies over the monitoring period in Nanjing.


2021 ◽  
Author(s):  
Jamie Fine

Society’s use of fossil fuels has led to increasingly high levels of CO2 in the atmosphere. These levels have been linked to global average temperature rises, and increases in the severity and frequency of major weather events. To combat these effects, nations around the world have committed to reducing their CO2 emissions, and transition to renewable energy. This thesis focuses on the development of a novel solar heating system, which combines a hybrid solar panel and cascade heat pump. The thesis begins by presenting a high-level literature review of solar and heat pump technologies, followed by the initial design development of the system. Two design iterations are presented, illustrating that the final design was selected because it exhibits improved peak heat output, and reduced sensitivity to panel temperature. Next, a manuscript-based chapter is presented that focuses on utilizing the proposed solar heating system for water distillation. Case studies are presented that compare the performance of the proposed system with a solar still at four different locations. The final conclusion from these studies is that using the proposed system offers area-based performance improvements of 780% compared to a basic solar still. A second manuscript-based study is then presented, which focuses on utilizing the proposed solar heating system for domestic hot water production. Additional case studies are detailed that compare the proposed system to an evacuated tube design, and a single heat pump. The conclusions from these studies are that the proposed system exceeds the performance of the evacuated tube system by up to 64%, and that the proposed system is most beneficial during seasons with higher average dry-bulb temperatures, and increased solar irradiation. A final manuscript-based study is then presented, which focuses on a methodology for improving alternate mode thermal performance estimates for hybrid solar panels. The conclusion from this study is that the proposed methodology can successfully estimate thermal performance within 5% of actual values. Each of these studies contributes to the project goal of developing a novel solar energy heating system, which can be further developed to reduce global CO2 emissions, and reduce the effects of climate change.


2021 ◽  
Author(s):  
Jamie Fine

Society’s use of fossil fuels has led to increasingly high levels of CO2 in the atmosphere. These levels have been linked to global average temperature rises, and increases in the severity and frequency of major weather events. To combat these effects, nations around the world have committed to reducing their CO2 emissions, and transition to renewable energy. This thesis focuses on the development of a novel solar heating system, which combines a hybrid solar panel and cascade heat pump. The thesis begins by presenting a high-level literature review of solar and heat pump technologies, followed by the initial design development of the system. Two design iterations are presented, illustrating that the final design was selected because it exhibits improved peak heat output, and reduced sensitivity to panel temperature. Next, a manuscript-based chapter is presented that focuses on utilizing the proposed solar heating system for water distillation. Case studies are presented that compare the performance of the proposed system with a solar still at four different locations. The final conclusion from these studies is that using the proposed system offers area-based performance improvements of 780% compared to a basic solar still. A second manuscript-based study is then presented, which focuses on utilizing the proposed solar heating system for domestic hot water production. Additional case studies are detailed that compare the proposed system to an evacuated tube design, and a single heat pump. The conclusions from these studies are that the proposed system exceeds the performance of the evacuated tube system by up to 64%, and that the proposed system is most beneficial during seasons with higher average dry-bulb temperatures, and increased solar irradiation. A final manuscript-based study is then presented, which focuses on a methodology for improving alternate mode thermal performance estimates for hybrid solar panels. The conclusion from this study is that the proposed methodology can successfully estimate thermal performance within 5% of actual values. Each of these studies contributes to the project goal of developing a novel solar energy heating system, which can be further developed to reduce global CO2 emissions, and reduce the effects of climate change.


2019 ◽  
Vol 9 (15) ◽  
pp. 3048
Author(s):  
Reyhaneh Loni ◽  
Gholamhassan Najafi ◽  
Ezzatollah Askari Asli-Ardeh ◽  
Barat Ghobadian ◽  
Willem G. Le Roux ◽  
...  

A parabolic solar dish concentrator, as the heat source of an organic Rankine cycle (ORC), can be used for power generation. Different types of tubular cavity receivers with different nanofluids can be considered for use in the solar dish collector to improve its efficiency. In the current research, an ORC with three different cavity receivers including hemispherical, cubical, and cylindrical are investigated using three nanofluids: Al2O3/oil, CuO/oil, and SiO2/oil. A numerical model is validated using experimental data. The ORC analysis is done for a constant evaporator pressure of 2.5 MPa, and condenser temperature of 38 °C. Methanol is employed as the ORC’s working fluid and a non-regenerative, ideal ORC system with different turbine inlet temperatures is considered. Furthermore, a fixed solar heat transfer fluid flow rate of 60 mL/s and dish diameter of 1.9 m is investigated. Results show that, compared to pure oil, the thermal efficiency of the cavity receivers increases slightly, and the pressure drop increases with the application of nanofluids. Furthermore, results show that the cubical cavity receiver, using oil/Al2O3 nanofluid, is the most efficient choice for application as the investigated solar ORC’s heat source.


1991 ◽  
Vol 113 (2) ◽  
pp. 337-340 ◽  
Author(s):  
P. Bannister

The problem of optimizing the radius of boiler tubes in a radiation-dominated environment such as a solar thermal power receiver is examined. The trade-off between heat transfer and pumping power is investigated, resulting in an explicit expression for the radius that maximizes the net exergy gain under turbulent flow conditions. The effect of the pumping power being generated on site is included, thus making the result particularly applicable to the design of stand-alone power systems. Examples using typical design values for small parabolic dish solar thermal collectors using water and steam as the working fluid are given to illustrate the characteristics of the problem.


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