Effective Approaches for the Improvement of Solar Energy Collector Efficiency in Town Buildings

2012 ◽  
Vol 209-211 ◽  
pp. 1723-1726
Author(s):  
Yun Peng Zhang ◽  
Shun Xiang Sun ◽  
Yan Hou
Keyword(s):  
Solar Energy ◽  
Clean Energy ◽  
Building Energy ◽  
Absorption Efficiency ◽  
Solar Thermal ◽  
Thermal Arrest ◽  
Energy Usage ◽  
Solar Absorption ◽  
Collector Efficiency ◽  
Energy Shortage

In order to reasonably make good use of solar energy---a kind of typical and clean energy, especially increase the efficiency of solar energy usage in town buildings, this paper introduces and analyzes solar Thermal-arrest Technology by way of how to increase solar absorption efficiency and how to decrease collector heat loss, finds an effective way to increase the efficiency of present solar collectors. Solar Thermal-arrest Technology is good for being widely used in town buildings. Its reasonable development is helpful to reducing building energy consumption and the relief of present energy shortage in China.

Considerations for the Design of Solar-Thermal Chemical Processes

2010 ◽  
Vol 132 (3) ◽  
Author(s):  
Janna Martinek ◽  
Melinda Channel ◽  
Allan Lewandowski ◽  
Alan W. Weimer
Keyword(s):  
Solar Energy ◽  
Water Splitting ◽  
Thermal Reduction ◽  
Absorption Efficiency ◽  
Chemical Processes ◽  
Solar Thermal ◽  
System Efficiency ◽  
Field Efficiency ◽  
Definition Of ◽  
Solar Field

A methodology is presented for the design of solar thermal chemical processes. The solar receiver efficiency for the high temperature step, defined herein as the ratio of the enthalpy change resulting from the process occurring in the receiver to the solar energy input, is limited by the solar energy absorption efficiency. When using this definition of receiver efficiency, both the optimal reactor temperature for a given solar concentration ratio and the solar concentration required to achieve a given temperature and efficiency shift to lower values than those dictated by the Carnot limitation on the system efficiency for the conversion of heat to work. Process and solar field design considerations were investigated for ZnO and NiFe2O4 “ferrite” spinel water splitting cycles with concentration ratios of roughly 2000, 4000, and 8000 suns to assess the implications of using reduced solar concentration. Solar field design and determination of field efficiency were accomplished using ray trace modeling of the optical components. Annual solar efficiency increased while heliostat area decreased with increasing concentration due to shading and blocking effects. The heliostat fields designed using system efficiency for the conversion of heat to work were found to be overdesigned by up to 21% compared with those designed using the receiver efficiency alone. Overall efficiencies of 13–20% were determined for a “ferrite” based water splitting process with thermal reduction conversions in the range of 35–100%.

scholarly journals Solar Energy Potential in Turkey

2005 ◽  
Vol 23 (1) ◽  
pp. 61-69 ◽  
Author(s):  
Havva Balat
Keyword(s):  
Solar Radiation ◽  
Solar Energy ◽  
Geographical Location ◽  
Clean Energy ◽  
Energy Resources ◽  
Solar Thermal ◽  
Energy Potential ◽  
Yearly Average ◽  
Solar Thermal Applications

In this study, the solar energy potential of Turkey was investigated. Among the alternative clean energy resources in Turkey, the most important one is solar energy. Turkey's solar energy potential has been estimated to be 26.4 million toe as thermal and 8.8 million toe as electricity. Generally, solar energy is used for heating and the consumption of solar energy has increased from 5 ktoe in 1986 to 335 ktoe in 2003. Turkey's geographical location is highly favourable for utilization of solar energy. The yearly average solar radiation is 3.6 kWh/(m2 day) and the total yearly insulation period is approximately 2460 hours, which is sufficient to provide adequate energy for solar thermal applications.

scholarly journals Experimental Research on the Selective Absorption of Solar Energy by Hybrid Nanofluids

Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8186
Author(s):  
Xin Jin ◽  
Guiping Lin ◽  
Haichuan Jin ◽  
Zunru Fu ◽  
Haoyang Sun
Keyword(s):  
Solar Energy ◽  
Low Cost ◽  
Clean Energy ◽  
Absorption Efficiency ◽  
Working Fluid ◽  
Hybrid Nanofluid ◽  
Selective Absorption ◽  
Solar Collectors ◽  
Direct Absorption ◽  
Hybrid Nanofluids

As low-cost, widely distributed and easily accessible renewable clean energy, solar energy has attracted more and more attention. Direct absorption solar collectors can convert solar energy into heat, but their efficiency is closely related to the absorption performance of the working fluid. In order to improve the absorption efficiency of direct absorption solar collectors, an experimental study on the selective absorption of solar energy by hybrid nanofluids was carried out. Five hybrid nanofluids were prepared and characterized, and the energy transfer advantages of hybrid nanofluid over single nanofluid were carefully studied. Experiments have found that the light-to-heat conversion properties of hybrid nanofluids show no obvious advantages or disadvantages compared with single nanofluid, and their performance is closely related to the types of nanoparticles. In addition, the hybrid nanofluid generally has two peaks, exactly the same as the single nanofluid in the mixed component, but the absorption curve is flatter than that of the single nanofluid. Further research of more types of hybrid nanofluids can provide new insights into the use of solar energy.

Solar Energy Used in Intelligence-Ecology Building

2012 ◽  
Vol 512-515 ◽  
pp. 159-162
Author(s):  
Jin Mei Feng ◽  
Xiang Ping Zhu ◽  
Jian Ping Luo
Keyword(s):  
Solar Energy ◽  
Energy Saving ◽  
Natural Resource ◽  
Human Body ◽  
Natural Environment ◽  
Clean Energy ◽  
Energy Usage ◽  
Green Earth ◽  
Intelligent Technology ◽  
Modern Building

In modern building, it is the irresistible trend to combine intelligence and ecology, for such intelligence-ecology building, ecology is goal and intelligence is method. In such building, comfortable for human being and natural environment preservation is not conflict. In order to achieve the ecology goal, which means energy-saving, environmental-protection, green-earth, and to utilize the natural resource in most efficient ways, it has to use the intelligent technology. In intelligence-ecology building, the comfortable for human body and zero-consumption of energy can be accomplished simultaneously by using intelligent technology to raise the solar energy usage substantially and to utilize the clean energy efficiently in heating, ventilating, refrigerating, and power- generating.

scholarly journals Eliminate obstacles of use the solar systems as buildings facades using multilayers optical interference filters

2021 ◽  
Vol 3 (8) ◽  
pp. 83-91
Author(s):  
Zainab I. AL-Assadi ◽  
Fawzia Asadi ◽  
Ban M. Alameri
Keyword(s):  
Solar Energy ◽  
Clean Energy ◽  
Solar Thermal ◽  
Design Stage ◽  
Solar Systems ◽  
Building Facades ◽  
Solar Thermal Collectors ◽  
Metallic Strip ◽  
Aesthetic Aspect ◽  
Black Color

The Building design in a correct way and totalitarian requires integration of using solar energy technologies in the architectural design stage of the roofs and facades as the most appropriate places to obtain solar energy because it greatly affects the architectural aesthetic. This integration has to be taken into account at the design stage, which leads to effective and attractive solutions. Architecture needs the energy to complete its functions to increases human effectiveness and ability to do its tasks better, solar energy is the main factor of providing the necessary energy due to its abundance as well as being clean energy and does not cause polluting emissions to the environment. To provide a comfortable indoor environment for the occupants, Solar Thermal Collectors (STC) and Photovoltaics Cells (PV) used, which convert solar energy into thermal energy and electrical energy, respectively. The main problem of this study is concerning with the problems of the black color, visible tubes, metallic strip gradients (absorption strip), and welding points of the solar systems which gives the facades of the buildings an undesirable view and weakens the aesthetic aspect of the buildings and limits the abilities of architects to use because of their black color and undesirable aspect. The aim of this study is a design of optical interference filter (multilayer coatings) prepared by RF magnetron sputtering as a solution to the problem of black color, visible tubes, metallic strip gradients (absorption strip), and welding points in solar thermal collectors and photovoltaic cells, which are the main reasons for not using solar systems as building facades, this technique works to increase the efficiency of the solar systems and increase the amount of clean energy generated, also enhancing the expressive and aesthetic aspect of facades of buildings. In the NIR region this filter works as an anti-reflective coating. Also the coating includes a high color reflection at a certain wavelength in the VIS region to give the solar system an aesthetic feature, which is used as building facades by using appropriate dielectric substances with high and low reflective indexes likes SiO2 and MgF2 respectively. The results of the study showed that the increase in the number of layers will lead to an increase in the visible reflectivity peak, while near of infrared region remains an anti-reflective with a high Transmission of solar rays, thus increasing solar systems efficiency.

Efficient Co-Harvesting of Solar Energy and Low-Grade Heat by Molecular Photoswitches for High Energy Density, Long-Term Stable Solar Thermal Battery

2019 ◽  
Author(s):  
Zhao-Yang Zhang ◽  
Tao LI
Keyword(s):  
Energy Density ◽  
Solar Energy ◽  
High Performance ◽  
High Energy ◽  
Solar Thermal ◽  
High Energy Density ◽  
Low Grade ◽  
Thermal Battery ◽  
Low Grade Heat

Solar energy and ambient heat are two inexhaustible energy sources for addressing the global challenge of energy and sustainability. Solar thermal battery based on molecular switches that can store solar energy and release it as heat has recently attracted great interest, but its development is severely limited by both low energy density and short storage stability. On the other hand, the efficient recovery and upgrading of low-grade heat, especially that of the ambient heat, has been a great challenge. Here we report that solar energy and ambient heat can be simultaneously harvested and stored, which is enabled by room-temperature photochemical crystal-to-liquid transitions of small-molecule photoswitches. The two forms of energy are released together to produce high-temperature heat during the reverse photochemical phase change. This strategy, combined with molecular design, provides high energy density of 320-370 J/g and long-term storage stability (half-life of about 3 months). On this basis, we fabricate high-performance, flexible film devices of solar thermal battery, which can be readily recharged at room temperature with good cycling ability, show fast rate of heat release, and produce high-temperature heat that is >20<sup> o</sup>C higher than the ambient temperature. Our work opens up a new avenue to harvest ambient heat, and demonstrate a feasible strategy to develop high-performance solar thermal battery.

Efficient Co-Harvesting of Solar Energy and Low-Grade Heat by Molecular Photoswitches for High Energy Density, Long-Term Stable Solar Thermal Battery

2019 ◽  
Author(s):  
Zhao-Yang Zhang ◽  
Tao LI
Keyword(s):  
Energy Density ◽  
Solar Energy ◽  
High Performance ◽  
High Energy ◽  
Solar Thermal ◽  
High Energy Density ◽  
Low Grade ◽  
Thermal Battery ◽  
Low Grade Heat

Solar energy and ambient heat are two inexhaustible energy sources for addressing the global challenge of energy and sustainability. Solar thermal battery based on molecular switches that can store solar energy and release it as heat has recently attracted great interest, but its development is severely limited by both low energy density and short storage stability. On the other hand, the efficient recovery and upgrading of low-grade heat, especially that of the ambient heat, has been a great challenge. Here we report that solar energy and ambient heat can be simultaneously harvested and stored, which is enabled by room-temperature photochemical crystal-to-liquid transitions of small-molecule photoswitches. The two forms of energy are released together to produce high-temperature heat during the reverse photochemical phase change. This strategy, combined with molecular design, provides high energy density of 320-370 J/g and long-term storage stability (half-life of about 3 months). On this basis, we fabricate high-performance, flexible film devices of solar thermal battery, which can be readily recharged at room temperature with good cycling ability, show fast rate of heat release, and produce high-temperature heat that is >20<sup> o</sup>C higher than the ambient temperature. Our work opens up a new avenue to harvest ambient heat, and demonstrate a feasible strategy to develop high-performance solar thermal battery.

Sign in / Sign up

Export Citation Format

Share Document