Parabolic Trough

The project aims at solving the alarming issue of water scarcity and sterilization by developing a system that would utilize solar energy which is a renewable source for the purification of unclean water from various water bodies to produce pure potable water. This system involves an evacuated tube containing water which is superheated using solar energy under elevated pressures to increase the boiling point. This high pressure superheated water is used for steam sterilization in an autoclave. The steam after sterilization can be condensed to generate pure water using a copper coil heat exchanger. This system can be effectively used in rural as well as coastal areas where energy sources other than solar are limited to generate potable water.In this process, water is pressurized to raise its boiling point. When this occurs, steam will be created at a temperature higher than 100°C. In fact, in order to fully eliminate all prions and bacteria associated with disease, saturated steam needs to be at least 121°C when in contact with the equipment being sterilized. A solar autoclave provides an alternative solution to this problem. Using only solar radiation, a solar autoclave can provide remote health clinics with an inexpensive, efficient way to sterilize medical equipment. The steam generated inside the autoclave is condensed to give pure water using a simple heat exchanger.

Since usage of fossil fuels for producing electricity causes climate change, renewable energy options have become one of the best substitution for fossil fuels. Solar energy promises high amount of resources for producing electricity. Among solar energy alternatives, Photovoltaic (PV) and Parabolic Trough Collectors (PTC) are dominant in the market. This paper compares middle size of PV and PTC power plant for the electricity need of Middle East Technical University Northern Cyprus Campus. Based on the maximum hourly demand of METU NCC, both PV and PTC are sized to 3 MWe. The simulations were performed via SAM software using the hourly values from typical meteorological data, which include solar irradiation, wind speed, dry and wet bulb temperatures, relative humidity and pressure. For the PTC and PV plants, commercially available components are used. The scenario assumes METU NCC to be a grid-connected micro-grid with one-way tariff, so that any deficit energy can be met by the uti...

The present paper aims to the techno-economic feasibility of enhancing low-cost parabolic trough collectors in the light of developing the use of solar energy in under-developed regions where expensive high-tech solar devices cannot be afforded. Moreover, the collector is aimed to produce steam so that its performance is based on heat which can be discovered. In this regard, the manufacturing process and the detailed design models in Solidworks software are elaborated. Furthermore, the colletor's material is chosen in a way to minimize the costs. Finally, to assess the performance of the built collector, it is installed in the site of Shahid Beheshti University, Tehran, and the values of the effective peripheral parameters, such as temperature, wind speed, and most importantly, solar irradiance, are recorded simultaneously in June. According to the results obtained, the manufactured collector with the aperture area of 2 m<sup>2</sup> (1×2 m) is capable of producing 3...

Energy and exergy efficiency amelioration of the parabolic trough has taken high interest since recent years, especially when nanofluid used as an enhancement category. This paper aimed to improve LS-2 parabolic trough model and compare the enhancement effect that occurred using different mono and hybrid nanofluids. Inserting mono nanoparticles of Al2O3, CeO2, CuO, and hybrid combinations of Al2O3 with CeO2, or CuO nanoparticles in a Syltherm 800 was investigated by five different cases. The investigation was presented under total volume fraction 4% for all nanofluids and mixing fraction 50:50 for the hybrid types in order to facilitate the analysis and compare various results at the same conditions. Those cases and their comparisons were solved using MATLAB Symbolic tools under turbulent flow regime and variable inlet temperature to present wide domain behavior for the energy and exergy efficiency, Nusselt number, heat transfer coefficient, and pressure drop, whereas the analytical...

Parabolic Trough Collectors are widespread in CSP applications. Their adoption is less developed in industrial heat demand applications. In the present thesis the design and test of two prototypes of PTC for the thermal loads in the range 80-250 °C is described. A mathematical model has also been developed to predict optical efficiency and thermal losses for any PTC. The model has been validated through comparison with the experimental results on the prototypes. Then it has been included in a custom-built simulation environment to predict yearly performances of a PTC field coupled with an industrial process heat demand. Energetic results are shown and final considerations are drawn for this application.

India is one of the largest contributors to the world?s agricultural products. The majority of people?s livelihood in India depends on agriculture and its allied sectors. According to an economics survey in the agricultural year of 2019-2020, India is estimated to have produced around 292 million tonnes of food grain. The share of agriculture in India?s GDP is 19.9%. Even though India is an active participant in global agricultural trade, the total agricultural product export is only 2.5%. Agricultural produce is easily perishable and the quality gets affected which will then affect their market value. To meet the future food demands, agricultural produce must be able to store for a longer amount of time for round the year availability. The traditional food storage practices cannot satisfy that condition. These perishables need a proper cold supply chain to increase the shelf life. In this paper performance of a Parabolic Trough Collector Integrated Vapor Absorption Refrigeration sy...

ABSTRACT Boosting the optical and thermal efficiencies of parabolic trough concentrators is gaining renewal global interest for improving the overall concentrating solar power plant efficiency and reducing the specific costs of power generation. Using internal radiation heat shields in the annular space of the heat collection element is an attractive passive solution that is not well-addressed in the literature. This study is a first attempt to analyze and map both energetic and exergetic performances of parabolic trough concentrators in terms of the configuration of the radiation heat shield and the operating conditions of the concentrator. A 3D model based on Monte-Carlo ray tracing and computational fluid dynamics is developed, validated, and used to examine 420 combinations of design and operating parameters. The proposed design outperformed the conventional one in the whole spectrum of operating conditions, except for a narrow range of low operating temperatures and high flow rates. Floating radiation heat shields with small diameters and large shading angles enhanced the temperature uniformity of heat collection element and showed the highest enhancement ratios of both energy and exergy efficiencies, which were up to 15.4 and 14.4%, respectively. A radiation heat shield with a diameter of 75 mm and a shading angle of 150° was found the best performing configuration for most operating conditions. Increasing the shield’s emissivity (0.06) to that of the absorber tube (0.14) reduced the energy and exergy efficiencies by up to 33.75 and 29.06 %, respectively. The effectiveness of the modified design was more pronounced at lower solar irradiance levels. The enhancements of energy and exergy efficiency decreased by 85.76 and 86.40 % as the irradiance increased from 200 to 1000 W/m2. However, the modified design was still more efficient at all considered values of emissivity and solar irradiance.

This paper presents effect of Regenerative Organic Rankine Cycle (RORC) on the performance of solar thermal power in Yogyakarta, Indonesia. Solar thermal power is a plant that uses solar energy as heat source. Indonesia has high humidity level, so that parabolic trough is the most suitable type of solar thermal power technology to be developed, where the design is made with small focal distance. Organic Rankine Cycle (ORC) is a Rankine cycle that use organic fluid as working fluid to utilize low temperature heat sources. RORC is used to increase ORC performance. The analysis was done by comparing ORC system with and without regenerator addition. Refrigerant that be used in the analysis is R123. Preliminary data was taken from the solar collector system that has been installed in Yogyakarta. The analysis shows that with 36 m total parabolic length, the resulting solar collector capacity is 63 kW, heat input/evaporator capacity is determined 26.78 kW and turbine power is 3.11 kW for O...

Since usage of fossil fuels for producing electricity causes climate change, renewable energy options have become one of the best substitution for fossil fuels. Solar energy promises high amount of resources for producing electricity. Among solar energy alternatives, Photovoltaic (PV) and Parabolic Trough Collectors (PTC) are dominant in the market. This paper compares middle size of PV and PTC power plant for the electricity need of Middle East Technical University Northern Cyprus Campus. Based on the maximum hourly demand of METU NCC, both PV and PTC are sized to 3 MWe. The simulations were performed via SAM software using the hourly values from typical meteorological data, which include solar irradiation, wind speed, dry and wet bulb temperatures, relative humidity and pressure. For the PTC and PV plants, commercially available components are used. The scenario assumes METU NCC to be a grid-connected micro-grid with one-way tariff, so that any deficit energy can be met by the utility and any excess energy produced by the suggested renewable energy systems will be given to the grid for free. The results indicate that 3 MW PV plant would generate annual energy of about 4.95 GWh with a capacity factor of 18.9%. These numbers would yield to a LCOE value of 2.60 ¢/kWh. On the other hand, the suggested 3 MW PTC plant with 2 solar multiple would supply about annual energy of 6.3 GWh at a capacity factor of 24.0%. The LCOE of the energy from PTC plant was estimated to be 8.47 ¢/kWh due to high capital and operation cost of PTC plants compared to PV plants. However, over years the cost of PTC power plants has been decreasing. Additionally, both PTC plant and PV plant would consume water only for cleaning purposes that makes them suitable for Cyprus water scarcity conditions. Overall, this study shows pros and cons of middle-sized PV and PTC plants with the case study of METU NCC.

Experimental study of solar heat transfer in a parabolic trough solar collector (PTSC) recording to the Iraq weather conditions in Ad Diwaniyah city (32o N, 45o E). Different parameters used; included varying the flow rate, focal length to test their effects on the performance of the collector. Three rates of water flow were used (2, 2.5, and 3 L/min). Results showed that; the performance of the collector increases when the mass flow rate increases. Furthermore, when the flow rate increased from 2-3 L /min, the useful heat gain and efficiency of the collector increased by 29 and 28% respectively. It also, can be seen the performance of the collector decreases as the focal length increase. Two different methods have been used to increase the energy obtained from the solar collector. The first method; by using of secondary reflectors and the second method; by using of fins. Two configurations of secondary reflectors were used named as; flat reflector and curved reflector. By using the first method, the efficiency of the collector increasing from 34.7-40.8%, while it increasing from 35.5-38.44% when the second method used.