Experimental Investigation of Heat Losses from a Heat Pipe Based Parabolic Trough Collector used for Direct Steam Generation

The performance of a thermosiphon based parabolic trough collector (PTC) used for direct steam generation depends largely on the heat losses of the solar thermal system. This paper presents an experimental investigation of the heat losses in a thermosiphon based solar thermal system that used a linear receiver with a PTC for the generation of low temperature steam. A locally constructed PTC was used to concentrate sun rays to a linear copper pipe enclosed in an evacuated glass tube and held at the focal line of the PTC to heat water and generate steam. Circulation of the water in the closed-loop solar thermal system was through natural convection. A solar meter was used to measure the incident radiation flux at the experimental site and PT100 temperature sensors were installed at different points of the system to measure the temperature distribution within the system. The thermal efficiency and overall heat losses of the system were investigated by fitting the experimental data to standard equations. The results showed that the instantaneous thermal efficiency of the system was 46.48%, 43.1% and 45.32% respectively for three days examined. The overall heat losses in the system were 1211.95, 974.32 and 911.26 kwh per day respectively for the three days investigated. Heat losses from the tank accounted for over 83% of the losses for all the days examined. The evacuated glass tube reduced heat losses from the receiver to very low values of 2.31, 1.63 and 1.43 KWh per day respectively for the three days tested. The use of a better insulating material on the tank was recommended to reduce convective and conductive heat losses, thereby enhancing the performance of the system.

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Experimental investigation and computational validation of heat losses from the cavity receiver used in linear Fresnel reflector solar thermal system

Renewable Energy ◽

10.1016/j.renene.2012.11.036 ◽

2013 ◽

Vol 55 ◽

pp. 18-23 ◽

Cited By ~ 18

Author(s):

Sudhansu S. Sahoo ◽

Shinu M. Varghese ◽

C. Suresh Kumar ◽

S.P. Viswanathan ◽

Suneet Singh ◽

...

Keyword(s):

Experimental Investigation ◽

Heat Losses ◽

Solar Thermal ◽

Thermal System ◽

Linear Fresnel Reflector ◽

Solar Thermal System ◽

Computational Validation

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Modelling and Design of Direct Solar Steam Generating Collector Fields

Journal of Solar Energy Engineering ◽

10.1115/1.1849225 ◽

2005 ◽

Vol 127 (3) ◽

pp. 371-380 ◽

Cited By ~ 66

Author(s):

M. Eck ◽

W.-D. Steinmann

Keyword(s):

Power Plants ◽

Thermal Power ◽

Solar Thermal ◽

Steam Generation ◽

Parabolic Trough ◽

Final Project ◽

Direct Steam ◽

Attractive Option ◽

The Stability ◽

Eu Project

The direct steam generation (DSG) is an attractive option regarding the economic improvement of parabolic trough technology for solar thermal electricity generation in the multi megawatt range. According to Price, H., Lu¨pfert, E., Kearney, D., Zarza, E., Cohen, G., Gee, R. Mahoney, R., 2002, “Advances in Parabolic Trough Solar Power Technology,” J. Sol. Energy Eng., 124 and Zarza, E., 2002, DISS Phase II-Final Project Report, EU Project No. JOR3-CT 980277 a 10% reduction of the LEC is expected compared to conventional SEGS like parabolic trough power plants. The European DISS project has proven the feasibility of the DSG process under real solar conditions at pressures up to 100 bar and temperatures up to 400°C in more than 4000 operation hours (Eck, M., Zarza, E., Eickhoff, M., Rheinla¨nder, J., Valenzuela, L., 2003, “Applied Research Concerning the Direct Steam Generation in Parabolic Troughs,” Solar Energy 74, pp. 341–351). In a next step the detailed engineering for a precommercial DSG solar thermal power plant will be performed. This detailed engineering of the collector field requires the consideration of the occurring thermohydraulic phenomena and their influence on the stability of the absorber tubes.

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Economic Potential of Solar Thermal Power Plants With Direct Steam Generation Compared With HTF Plants

Journal of Solar Energy Engineering ◽

10.1115/1.4001672 ◽

2010 ◽

Vol 132 (4) ◽

Cited By ~ 39

Author(s):

Jan Fabian Feldhoff ◽

Daniel Benitez ◽

Markus Eck ◽

Klaus-Jürgen Riffelmann

Keyword(s):

Thermal Power ◽

Solar Thermal ◽

Live Steam ◽

Steam Generation ◽

Parabolic Trough ◽

Electricity Cost ◽

Solar Thermal Power ◽

Technical Report ◽

Hourly Data ◽

Direct Steam

The direct steam generation (DSG) in parabolic trough collectors is a promising option to improve the mature parabolic trough solar thermal power plant technology of the solar energy generating systems (SEGS) in California. According to previous studies [Langenkamp, 1998, “Revised LEC Projections and Discussion of Different DSG Benefits,” Technical Report No. DISS-SC-QA-02, Almeria, Spain; Price, et al., 2002, “Advances in Parabolic Trough Solar Power Technology,” ASME J. Sol. Energy Eng., 124(2), pp. 109–125; Zarza, E., 2002, “DISS Phase II Final Report,” Technical Report EU Contract No. JOR3-CT98-0277, Almeria, Spain], the cost reduction in the DSG process compared with the SEGS technology is expected to be 8–25%. All these studies were more or less preliminary since they lacked detailed information on the design of collector fields, absorber tubes required for steam temperatures higher than 400°C, and power blocks adapted to the specific needs of the direct steam generation. Power blocks and collector fields were designed for four different capacities (5 MWel, 10 MWel, 50 MWel, and 100 MWel) and different live steam parameters. The live steam temperature was varied between saturation temperature and 500°C and live steam pressures of 40 bars, 64 bars, and 100 bars were investigated. To assess the different cases, detailed yield analyses of the overall system were performed using hourly data for the direct normal irradiation and the ambient temperature for typical years. Based on these results, the levelized costs of electricity were determined for all cases and compared with a reference system using synthetic oil as heat transfer fluid. This paper focuses on two main project findings. First, the 50 MWel DSG system parameter comparisons are presented. Second, the detailed comparison between a DSG and a SEGS-like 100 MWel system is given. The main result of the investigation is that the benefit of the DSG process depends on the project site and can reach an 11% reduction in the levelized electricity cost.

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An experimental investigation of the heat losses of a U-type solar heat pipe receiver of a parabolic trough collector-based natural circulation steam generation system

Renewable Energy ◽

10.1016/j.renene.2013.01.029 ◽

2013 ◽

Vol 57 ◽

pp. 262-268 ◽

Cited By ~ 27

Author(s):

Liang Zhang ◽

Zitao Yu ◽

Liwu Fan ◽

Wujun Wang ◽

Huan Chen ◽

...

Keyword(s):

Experimental Investigation ◽

Heat Pipe ◽

Natural Circulation ◽

Heat Losses ◽

Steam Generation ◽

Generation System ◽

Parabolic Trough ◽

Parabolic Trough Collector ◽

Solar Heat

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Economic Potential of Solar Thermal Power Plants With Direct Steam Generation Compared to HTF Plants

ASME 2009 3rd International Conference on Energy Sustainability, Volume 2 ◽

10.1115/es2009-90298 ◽

2009 ◽

Cited By ~ 2

Author(s):

Jan Fabian Feldhoff ◽

Daniel Benitez ◽

Markus Eck ◽

Klaus-Ju¨rgen Riffelmann

Keyword(s):

Thermal Power ◽

Saturation Temperature ◽

Solar Thermal ◽

Live Steam ◽

Steam Generation ◽

Parabolic Trough ◽

Electricity Cost ◽

Solar Thermal Power ◽

Hourly Data ◽

Direct Steam

The direct steam generation (DSG) in parabolic trough collectors is a promising option to improve the mature parabolic trough solar thermal power plant technology of the Solar Energy Generating Systems (SEGS) in California. According to previous studies [1–3], the cost reduction of the DSG process compared to the SEGS technology is expected to be 8 to 25%. All these studies were more or less preliminary since they lacked detailed information on the design of collector fields, absorber tubes required for steam temperatures higher than 400°C and power blocks adapted to the specific needs of the direct steam generation. To bridge this gap, a detailed system analysis was performed within the German R&D project DIVA. Power blocks and collector fields were designed for four different capacities (5, 10, 50 and 100 MWel) and different live steam parameters. The live steam temperature was varied between saturation temperature and 500°C, and live steam pressures of 40, 64 and 100 bar were investigated. To assess the different cases, detailed yield analyses of the overall system were performed using hourly data for the direct normal irradiation and the ambient temperature for typical years. Based on these results the levelized costs of electricity were determined for all cases and compared to a reference system using synthetic oil as heat transfer fluid (HTF). This paper focuses on two main project findings. First, the 50 MWel DSG system parameter comparisons are presented. Second, the detailed comparison between a DSG and a SEGS-like 100 MWel system is given. The main result of the investigation is that the benefit of the DSG process depends on the project site and can reach an 11% reduction of the levelized electricity cost (LEC).

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Experimental investigation of Versa Tyle GRP for solar thermal system

International Journal of Green Energy ◽

10.1080/15435075.2020.1831508 ◽

2020 ◽

Vol 18 (1) ◽

pp. 90-99

Author(s):

Mawada Abdellatif ◽

Stephen Baynes ◽

Yassin Osman ◽

Laurence Brady ◽

Jeff Cullen ◽

...

Keyword(s):

Experimental Investigation ◽

Solar Thermal ◽

Thermal System ◽

Solar Thermal System

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Design of automation control thermal system integrated with parabolic trough collector based solar plant

Thermal Science ◽

10.2298/tsci201113218n ◽

2021 ◽

pp. 218-218

Author(s):

Anbuchezhian Nattappan ◽

Suganya Priyadharshini Ganesan ◽

Velmurugan Thiagarajan ◽

Krishnamoorthy Ranganathan

Keyword(s):

Power Plant ◽

Solar Energy ◽

Solar Thermal ◽

Thermal System ◽

Solar Concentrator ◽

Parabolic Trough ◽

Parabolic Trough Collector ◽

Automation Control ◽

Solar Thermal System ◽

Noisy Condition

This paper presents enhanced design for Automation control of processes involved in a solar system which utilizes programmable logic controller to automate tracking system for obtaining maximum solar radiation. Three areas are involved in this proposed multi area system where first and second area considers solar power plant with thermal system based parabolic trough collector with fixed solar isolation and random isolation of solar energy whereas third area comprises of solar thermal system with dish Stirling realistic unit. Energy efficiency can be increased by using solar concentrator along with Stirling engine. Optimization of gain of the controller is by utilizing crow search novel algorithm. Crow search algorithm is an optimization technique, which provides better performance at complex time varying noisy condition and time in-varying noisy condition. The Proposed controller is evaluated by obtaining the optimized parameters of the system whose comparison is done by operating proposed controller with & without renewable sources of energy thereby revealing better performance for both conditions. Testing is done in different areas with fixed solar isolation and random stisolation of solar energy involved in solar thermal power plant based on parabolic trough collector. Gain and parameters of the controller of the solar power plant are optimized by utilizing automation for operation of solar concentrator with parabolic Trough collector. Data acquisition and monitoring is done by human machine interface (HMI) in order to report safe operation. The Simulation results of integrated solar thermal system involving dish Stirling with parabolic trough collector, shows that dynamic response of the proposed controller operating with renewable solar energy is better than that of non-renewable energy source.

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