Advanced solar energy utilization technology requires high-grade energy to achieve the most efficient application with compact size and least capital investment recovery period Concentrated solar power (CSP) technology has the capability to meet thermal energy and electrical demands Benefits of using CSP technology with parabolic trough collector (PTC) system include promising cost-effective investment, mature technology, and ease of combining with fossil fuels or other renewable energy sources This review first covered the theoretical framework of CSP technology with PTC system Next, the detailed derivation process of the maximum theoretical concentration ratio of the PTC was initially given Multiple types of heat transfer fluids in tube receivers were reviewed to present the capability of application Moreover, recent developments on heat transfer enhancement methods for CSP technology with PTC system were highlighted As the rupture of glass covers was frequently observed during application, methods of thermal deformation restrain for tube receivers were reviewed as well Commercial CSP plants worldwide with PTC system were presented, including those that are in operation, under construction, and announced Finally, possible further developments of CSP plants with PTC system were outlined Besides, suggestions for future research and application guidance were also illustrated

Progress in concentrated solar power technology with parabolic trough collector system: A comprehensive review

Hydrogen: A brief overview on its sources, production and environmental impact

Alternative designs of parabolic trough solar collectors

Modeling, simulation and performance analysis of parabolic trough solar collectors: A comprehensive review

Parabolic trough collector is one of the most usual solar collectors for applications up to 400 °C. The thermal enhancement of this collector concentrates a lot of interest and various techniques are tested in order for the thermal efficiency to be maximized with a reasonable penalty in the pressure drop. The use of nanofluids as working fluids, as well as the use of flow turbulators, mainly inserts and internal fins or tube dimples are the main techniques which are examined. The objective of this work is to give a complete literature review of the existing studies on this domain and to present a numerical comparative analysis between the most usual thermal enhancement techniques. More specifically, the use of oil-based nanofluids with 6% CuO is compared with the use of internal rectangular fins in the absorber, while the combination of these techniques is also examined. The analysis is conducted with a validated CFD model in SolidWorks Flow Simulation for various fluid temperature levels. According to the final results, the use of nanofluids leads to 0.76% thermal efficiency enhancement, the use of internal fins to 1.10% and the combination of these techniques to 1.54%. Moreover, emphasis is given in the pressure drop of the examined cases and in the evaluation criteria which are used in every case.

Enhancing the performance of parabolic trough collectors using nanofluids and turbulators

Heat transfer performance enhancement and thermal strain restrain of tube receiver for parabolic trough solar collector by using asymmetric outward convex corrugated tube

Hydrogen energy can help in solving the problem of greenhouse gas emissions which results in reduced global warming and stress on the fossil fuel supply and price, provided that hydrogen is produced by clean processes involving renewable energy. Solar hydrogen production via two-step thermochemical cycle is an appealing technique. This article attempts to present a review with aspect to solar thermochemical hydrogen production redox pairs, reactor design technology, general assessment, etc. Some novel reactors have been designed for different redox pairs in recent decade years. We give a comparison between different hydrogen technologies and summarize the problems that exist in the cycle. Though solar thermochemical hydrogen production technique is a promising and potential roacute to solve energy crisis problem, it still has many problems that need to be solved in the future.

Solar thermochemical hydrogen production using metallic oxides

Biomass gasification with steam/air is compared from an exergetic aspect. The comparison details include the exergy efficiencies of the product gases, tar, char and the lost part from the same biomass of both steam gasification and air gasification. Some conclusions can be obtained from the results. In the temperature range from 800? to 1200? analyzed in this paper, exergy efficiencies of both steam gasification and air gasification have the same changing tendency: gas exergy efficiency increases, while exergy efficiencies of tar and char decline. On the while, the exergy efficiencies of gases, tar and char of steam gasification are higher than that of air gasification. From this aspect, steam gasification is a better technology, especially when the tar and char can be efficiently used. When the gasification temperature increases, both these two technologies improve.

Exergy Analysis of Biomass Gasification with Steam/Air: A Comparison Study

Hydrogen production via biomass steam gasification and partial oxidation is analyzed from exergy aspect. Based on cypress sawdust gasified from 800 C to 1200 C, the exergy value of H2 from steam gasification rises from 1410.80 kJ kg-1 to 7922.89 kJ kg-1, while that from partial oxidation increases from 988.30 kJ kg-1 to 3097.81 kJ kg-1. The exergy efficiency of H2 from biomass also increases for both steam gasification (6.42 36.08%) and partial oxidation (4.50 14.11%). However, the exergy efficiencies of H2 from syngas are not in accordance. For steam gasification, the exergy efficiency rises sharply from 14.67% to 47.39%, and then increases slightly to 48.90%. For partial oxidation, the efficiency increases from 15.50% to 29.91% first, and then decreases slightly to 28.26%.

Exergy analysis of hydrogen production via biomass steam gasification and partial oxidation.

The comprehensive exergy characteristics of thirty two rice husk samples including exergy values (moisture related, S related, ash related, and LHV related) and exergy percentages (moisture related, S related, ash related, and LHV related) were investigated in this study. The results show that the moisture related exergy, S related exergy, ash related exergy, and LHV related exergy are in the ranges of 0-327.93, 0-67.78, 17.88-131.97, and 10577.05-19297.54 KJ/kg, respectively, for the rice husks. The exergy values of rice husks are in the range of 10918.01-19445.76 KJ/kg, and they are mainly determined by the LHV related exergy (96.81-99.70%), followed by moisture related exergy (0-2.66%), ash related exergy (0.11-0.78%), and S related exergy (0-0.43%).

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Li Bingxi

Papers

Heat transfer performance enhancement and thermal strain restrain of tube receiver for parabolic trough solar collector by using asymmetric outward convex corrugated tube

Solar thermochemical hydrogen production using metallic oxides

Exergy Analysis of Biomass Gasification with Steam/Air: A Comparison Study

Exergy analysis of hydrogen production via biomass steam gasification and partial oxidation.

Exergy characteristics of rice husks