Short-Duration Performance Acceptance Test of Parabolic Trough Solar Field: A Case Study

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Ali Elmaihy ◽  
Ahmed El Weteedy
Keyword(s):  
Renewable Energy ◽  
Steady State ◽  
Short Duration ◽  
Field Performance ◽  
Acceptance Test ◽  
National Renewable Energy Laboratory ◽  
Parabolic Trough ◽  
Short Period ◽  
Technical Specifications ◽  
Solar Field

Extensive solar field performance testing is often required as part of the plant commissioning process in order to ensure that actual solar field performance satisfies both technical specifications and performance guarantees between the involved parties. In this study, short duration (15 min) steady state performance acceptance test for Kuraymat integrated solar combined cycle (ISCC) solar field was carried out in agreement with the general guidelines of the earlier National Renewable Energy Laboratory (NREL) report on parabolic trough (PT) collector fields (Kearney, 2011, “Utility-Scale Parabolic Trough Solar Systems—Performance Acceptance Test Guidelines,” National Renewable Energy Laboratory, Golden, CO, NREL Report No. SR-5500-48895 and Kearney, 2010, “Development of Performance Acceptance Test Guidelines for Large Commercial Parabolic Trough Solar Fields,” National Renewable Energy Laboratory, Golden, CO, NREL Report No. SR-5500-49367) which is in full agreement with the plant documentations provided by FLAGSOL (2010, “Specification: Performance Test Procedure. Plant Documentations,” Customer Doc-ID: KU1-FLG-000-QP-M-001). This work includes measurement of the thermal power output of PT system under clear sky conditions over a short period during which thermal steady state conditions exist. The methodology of the solar field testing is presented while a special consideration is provided for the model formulation and uncertainty associated with the measured data. The measured results together with the associated uncertainties were compared with model predictions. All tests for both northern and a southern collector subfields that satisfy the test conditions are accepted based on acceptance test evaluation criteria.

scholarly journals Modeling of a Parabolic Trough Solar Field for Acceptance Testing: A Case Study

2011 ◽  
Author(s):  
Michael J. Wagner ◽  
Mark S. Mehos ◽  
David W. Kearney ◽  
Andrew C. McMahan
Keyword(s):  
Field Performance ◽  
Performance Model ◽  
Acceptance Testing ◽  
Acceptance Test ◽  
Model Formulation ◽  
Parabolic Trough ◽  
Actual Performance ◽  
Technical Specifications ◽  
Solar Field

As deployment of parabolic trough concentrating solar power (CSP) systems ramps up, the need for reliable and robust performance acceptance test guidelines for the solar field is also amplified. Project owners and/or EPC contractors often require extensive solar field performance testing as part of the plant commissioning process in order to ensure that actual solar field performance satisfies both technical specifications and performance guaranties between the involved parties. Performance test code work is currently underway at the National Renewable Energy Laboratory (NREL) in collaboration with the SolarPACES Task-I activity, and within the ASME PTC-52 committee. One important aspect of acceptance testing is the selection of a robust technology performance model. NREL1 has developed a detailed parabolic trough performance model [1] within the SAM software tool [2]. This model is capable of predicting solar field, sub-system, and component performance. It has further been modified for this work to support calculation at sub-hourly time steps. This paper presents the methodology and results of a case study comparing actual performance data for a parabolic trough solar field to the predicted results using the modified SAM trough model. Due to data limitations, the methodology is applied to a single collector loop, though it applies to larger subfields and entire solar fields. Special consideration is provided for the model formulation, improvements to the model formulation based on comparison with the collected data, and uncertainty associated with the measured data. Additionally, this paper identifies modeling considerations that are of particular importance in the solar field acceptance testing process and uses the model to provide preliminary recommendations regarding acceptable steady-state testing conditions at the single-loop level.

Annual Yield Analysis of Solar Tower Power Plants With GREENIUS

2011 ◽  
Vol 133 (3) ◽  
Author(s):  
Jürgen Dersch ◽  
Peter Schwarzbözl ◽  
Timo Richert
Keyword(s):  
Renewable Energy ◽  
Power Plants ◽  
Software Tool ◽  
Parabolic Trough ◽  
Concentrating Solar Power ◽  
Solar Field ◽  
Performance Calculation ◽  
Design Power ◽  
Energy Plants ◽  
Renewable Energy Plants

An existing software tool for annual performance calculation of concentrating solar power and other renewable energy plants has been extended to enable the simulation of solar tower power plants. The methodology used is shown and a demonstrative example of a 50 MWe tower plant in southern Spain is given. The influence of design power and latitude on solar field layout is discussed. Furthermore, a comparison of the tower plant with a 50 MWe parabolic trough and a Linear Fresnel plant at the same site is given.

Modeling and Thermal Performance Analysis of Parabolic trough Solar Field with Single-Axis Tracked

2012 ◽  
Vol 512-515 ◽  
pp. 101-108
Author(s):  
Jian Mao ◽  
Hong Juan Hou ◽  
Ji Feng Song ◽  
Song Gao
Keyword(s):  
Performance Analysis ◽  
Field Performance ◽  
Software Tool ◽  
Solar Irradiation ◽  
Parabolic Trough ◽  
Thermal Output ◽  
Solar Field ◽  
Performance Calculation ◽  
Mathematical Derivation ◽  
Direct Solar Irradiation

In this paper, a model of parabolic trough solar field with single-axis tracked was developed based on detailed mathematical derivation. A software tool is also developed for its performance calculation. By the model and software, the direct solar irradiation (DNI) intercepted by the collectors and the thermal output can be obtained for a given solar field under different tracking mode. To obtain the characters of the solar field performance with different tracking modes and regions, the annual performance of the solar field is evaluated for different sites in China such as Beijing, Lhasa. Besides that, the effect of the space between collector rows on thermal output of a solar field is also discussed.

The Effects of Heat Treatment on the Chemical Alterations of Oak Wood

2016 ◽  
Vol 688 ◽  
pp. 44-49 ◽  
Author(s):  
Iveta Čabalová ◽  
František Kačík ◽  
Tereza Tribulová
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
High Performance Liquid Chromatography ◽  
Renewable Energy ◽  
Liquid Chromatography ◽  
Thermal Treatment ◽  
High Performance ◽  
Treated Wood ◽  
National Renewable Energy Laboratory ◽  
Oak Wood

Samples prepared from oak (Quercusrobur L.) wood were exposed to heat treatment at temperatures of 160, 180, 200 and 220 oC for 3, 6, 9 and 12 hours. In both untreated and thermally treated wood there were determined extractives and lignin by National Renewable Energy Laboratory (NREL) procedures, cellulose by Seifert's method, holocellulose according to Wise, hemicelluloses as difference between holocellulose and cellulose. Monosaccharides were determined by high performance liquid chromatography (NREL).The results show that hemicelluloses are less stable at thermal treatment than cellulose. The amounts of lignin and extractives rose by increasing both temperature and time of the treatment while the amounts of hemicelluloses decreased. Thermal treatment also resulted in significant decreases of the yields of non-glucosic saccharides. Degradation of carbohydrates can cause the deterioration of mechanical properties of wood.

Design Point for Predicting Year-Round Performance of Solar Parabolic Trough Concentrator Systems

2013 ◽  
Author(s):  
Men Wirz ◽  
Matthew Roesle ◽  
Aldo Steinfeld
Keyword(s):  
Operating Conditions ◽  
Transfer Model ◽  
Parabolic Trough ◽  
Specific System ◽  
Simple Method ◽  
Operating Condition ◽  
Average Efficiency ◽  
Design Point ◽  
Yearly Average ◽  
Solar Field

Thermal efficiencies of the solar field of two different parabolic trough concentrator (PTC) systems are evaluated for a variety of operating conditions and geographical locations, using a detailed 3D heat transfer model. Results calculated at specific design points are compared to yearly average efficiencies determined using measured direct normal solar irradiance (DNI) data as well as an empirical correlation for DNI. It is shown that the most common choices of operating conditions at which solar field performance is evaluated, such as the equinox or the summer solstice, are inadequate for predicting the yearly average efficiency of the solar field. For a specific system and location, the different design point efficiencies vary significantly and differ by as much as 11.5% from the actual yearly average values. An alternative simple method is presented of determining a representative operating condition for solar fields through weighted averages of the incident solar radiation. For all tested PTC systems and locations, the efficiency of the solar field at the representative operating condition lies within 0.3% of the yearly average efficiency. Thus, with this procedure, it is possible to accurately predict year-round performance of PTC systems using a single design point, while saving computational effort. The importance of the design point is illustrated by an optimization study of the absorber tube diameter, where different choices of operating conditions result in different predicted optimum absorber diameters.

Development of an Innovative Code for the Design of Different Parabolic Trough Solar Fields

2009 ◽  
Author(s):  
Ennio Macchi ◽  
Giampaolo Manzolini ◽  
Paolo Silva
Keyword(s):  
Solar Energy ◽  
Energy Demand ◽  
Working Fluid ◽  
Fluid Temperature ◽  
Parabolic Trough ◽  
High Solar Radiation ◽  
Power Block ◽  
The Usa ◽  
Solar Field ◽  
Steam Cycle

The role of renewable energies and in particular solar energy could be fundamental in future scenarios of worldwide increase of energy demand: thermodynamic solar energy can play an important role in country with high solar radiation. This paper discusses the development and testing of an innovative code for the prediction of thermodynamic performances at nominal conditions and the estimation of costs of the whole plant, for different parabolic trough solar fields. The code allows a preliminary design of the solar field lay-out, the sizing of the main components of the plant and the optimization of the steam cycle. The code, named PATTO (PArabolic Trough Thermodynamic Optimization), allows to separately calculate the thermal efficiency of (i) parabolic trough systems in commerce as well as (ii) combination of components of various commercial systems, in order to exploit different technology solutions: combination of mirrors, receivers and supports. Using the selected parabolic troughs, the plant configuration is then completed by connecting pipes, heat exchangers, the steam cycle, and storage tanks. The code is also flexible in terms of working fluid, temperature and pressure range. Regarding the power block, a conventional steam cycle with super-heater and re-heater sections and up to seven regenerative bleedings is adopted. It is possible to use also simpler configuration as without re-heater or with less regenerative bleedings. Moreover, thanks to simple or sophisticated economic correlations depending on available data, the code calculates the overall investment cost for the considered solar field and the power block. The code performs steady state analysis at nominal conditions, while future developments are planned regarding part load analysis and transient simulations. The model is tested towards real applications and reference values found in literature; in particular, focusing on SEGS VI plant in the USA. Detailed results showing code potentiality, are presented in terms of solar field and power block energy balances, plant auxiliaries, piping and economic analysis.

Performance Enhancement of Solar Parabolic Trough Collector Using Intensified Ray Convergence System

2017 ◽  
Vol 867 ◽  
pp. 191-194
Author(s):  
Anbu Manimaran Sukanta ◽  
M. Niranjan Sakthivel ◽  
Gopalsamy Manoranjith ◽  
Loganathan Naveen Kumar
Keyword(s):  
Renewable Energy ◽  
Solar Energy ◽  
Performance Enhancement ◽  
Solar Flux ◽  
Parabolic Trough ◽  
Parabolic Trough Collector ◽  
Chrome Coating ◽  
Convergence System ◽  
And Performance

Solar Energy is one of the forms of Renewable Energy that is available abundantly. This work is executed on the enhancement of the performance of solar parabolic trough collector using Intensified Ray Convergence System (IRCS). This paper distinguishes between the performance of solar parabolic trough collector with continuous dual axis tracking and a fixed solar parabolic trough collector (PTC) facing south (single axis tracking). The simulation and performance of the solar radiations are visualized and analyzed using TRACEPRO 6.0.2 software. The improvement in absorption of solar flux was found to be enhanced by 39.06% in PTC using dual axis tracking, absorption of solar flux increases by 52% to 200% in PTC receiver using perfect mirror than PTC using black chrome coating.

"Steady-state" competence for bacterial transformation

1968 ◽  
Vol 14 (3) ◽  
pp. 290-292
Author(s):  
Herbert H. Eichhorn ◽  
Shigeyo Arikawa ◽  
Stephen Zamenhof
Keyword(s):  
Bacillus Subtilis ◽  
Steady State ◽  
Continuous Culture ◽  
Generation Time ◽  
Bacterial Transformation ◽  
Short Period ◽  
Minimal Media ◽  
Harmful Effects ◽  
Specific Phase

The cells of Bacillus subtilis, grown in minimal media, are known to become competent for transformation for a short period at a specific phase of ceil growth. In the present work the cells (strain 168 ind−) were grown in continuous culture (chemostat; glucose limiting, generation time 4 h, 37 °C). Aliquots were removed at 20- to 24-h intervals and immediately tested for competence. The viability (41 h) was 97%. The initial very low competence increased up to 200-fold within the 24 h and remained at this high, slowly decreasing level for at least 168 h. It is concluded that a long-lasting competence may develop and persist in the cells in continuous culture ("steady-state"), without demonstrable harmful effects to the population.

Sign in / Sign up

Export Citation Format

Share Document