Design and Analysis of a High Temperature Particulate Hoist for Proposed Particle Heating Concentrator Solar Power Systems

Author(s):  
Kenzo K. D. Repole ◽  
Sheldon M. Jeter

The central receiver power tower (CRPT) with a particle heating receiver (PHR) is a form of concentrating solar power (CSP) system with strong potential to achieve high efficiency at low cost and to readily incorporate cost-effective thermal energy storage (TES). In such a system, particulates are released into the PHR, and are heated to high temperature by concentrated solar radiation from the associated heliostat field. After being heated, the particles will then typically flow into the hot bin of the TES. Particulates accumulated in the hot bin can flow through a heat exchanger to energize a power generation system or be held in the hot TES storage bin for later use such as meeting a late afternoon peak demand or even overnight generation. Particles leaving the heat exchanger are held in the low temperature bin of the TES. A critical component in such a PHR system is the particle lift system, which must transport the particulate from the lower temperature TES bin back to the PHR. In our baseline 60 MW-thermal (MW-th) design, the particulate must be lifted around 70 m at the rate of 128 kg/s. For the eventual commercial scale system of a 460 MW-th design the particulate must be lifted around 138 m at the rate of 978 kg/s. The obvious demands on this subsystem require the selection and specification of a highly efficient, economical, and reliable lift design. After an apparently exhaustive search of feasible alternatives, the skip hoist was selected as the most suitable general design concept. While other designs have not been dismissed, our currently preferred somewhat more specific preliminary design employs a Kimberly Skip (KS) in a two-skip counterbalanced configuration. This design appears to be feasible to fabricate and integrate with existing technology at an acceptably low cost per MW-th and to promise high overall energy use efficiency, long service life, and low maintenance cost. A cost and performance model has been developed to allow optimization of our design and the results of that study are also presented. Our developed design meets the relevant criteria to promote cost effective CSP electricity production.

2020 ◽  
Vol 143 (3) ◽  
Author(s):  
Zhiwen Ma ◽  
Janna Martinek

Abstract Concentrating solar power (CSP) development has focused on increasing the energy conversion efficiency and lowering the capital cost. To improve performance, CSP research is moving to high-temperature and high-efficiency designs. One technology approach is to use inexpensive, high-temperature heat transfer fluids and storage, integrated with a high-efficiency power cycle such as the supercritical carbon dioxide (sCO2) Brayton power cycle. The sCO2 Brayton power cycle has strong potential to achieve performance targets of 50% thermal-to-electric efficiency and dry cooling at an ambient temperature of up to 40 °C and to reduce the cost of power generation. Solid particles have been proposed as a possible high-temperature heat transfer or storage medium that is inexpensive and stable at high temperatures above 1000 °C. The particle/sCO2 heat exchanger (HX) provides a connection between the particles and sCO2 fluid in emerging sCO2 power cycles. This article presents heat transfer modeling to analyze the particle/sCO2 HX design and assess design tradeoffs including the HX cost. The heat transfer process was modeled based on a particle/sCO2 counterflow configuration, and empirical heat transfer correlations for the fluidized bed and sCO2 were used to calculate heat transfer area and estimate the HX cost. A computational fluid dynamics simulation was applied to characterize particle distribution and fluidization. This article shows a path to achieve the cost and performance objectives for a particle/sCO2 HX design by using fluidized-bed technology.


Catalysts ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1547
Author(s):  
Shivaraj Patil ◽  
Ji-Yao An ◽  
Zhi-Jie Li ◽  
Yu-Cheng Wu ◽  
Swathi M. Gowdru ◽  
...  

The high dependence on and high cost of lithium has led to a search for alternative materials. Aluminum ion batteries (AIBs) have gained interest due to their abundance, low cost, and high capacity. However, the use of the expensive 1-ethyl-3-methylimidazolium chloride (EMIC) electrolyte in AIBs curtails its wide application. Recently, high-temperature batteries have also gained much attention owing to their high demand by industries. Herein, we introduce cost-effective 1T molybdenum sulfide grown on SP-1 graphite powder (1T-MoS2/SP-1) as a cathode material for high-temperature AIBs using the AlCl3-urea eutectic electrolyte (1T-MoS2/SP-1–urea system). The AIB using the 1T-MoS2/SP-1–urea system exhibited a capacity as high as 200 mAh/g with high efficiency of 99% over 100 cycles at 60 °C when cycled at the rate of 100 mA/g. However, the AIB displayed a capacity of 105 mAh/g when cycled at room temperature. The enhanced performance of the 1T-MoS2/SP-1–urea system is attributed to reduced viscosity of the AlCl3-urea eutectic electrolyte at higher temperatures with high compatibility of 1T-MoS2 with SP-1. Moreover, the electrocatalytic lithiation of 1T-MoS2 and its effect on the hydrogen evolution reaction were also investigated. We believe that our work can act as a beacon for finding alternative, cost-effective, and high-temperature batteries.


Author(s):  
Hany Al-Ansary ◽  
Abdelrahman El-Leathy ◽  
Sheldon Jeter ◽  
Matthew Golob ◽  
Clayton Nguyen ◽  
...  

Abstract Particle-based power tower systems are a promising technology that can allow operation of concentrating solar power (CSP) systems at temperatures higher than what today’s commercial molten salt systems can achieve, making them suitable for use in a variety of applications, including supercritical CO2 cycles, air Brayton cycles, and high-temperature process heat. In this concept, particles, instead of molten salt, are heated by the concentrated sunlight. In 2015, this concept was successfully tested at Sandia National Laboratories. In the mean time, an integrated system incorporating a particle heating receiver, a particle-to-air heat exchanger and a 100-kWe microturbine was designed, built, and tested at King Saud University in Riyadh, Saudi Arabia. The integrated system was run in 2018, and results from that test campaign were very promising, with temperatures of the particles leaving the receiver exceeding 600°C despite a number of challenges. The utility sponsoring the project is now planning to move forward with building a 1-MWe plant using the same concept, thereby moving closer to large-scale deployment, and making this facility the world’s first commercial concentrating solar power plant that uses the particle heating receiver concept. Moving from a 100-kWe scale to a 1-MWe scale requires modifications to the design of some components. The most likely plant location is the city of Duba in northwestern Saudi Arabia where the average daily total DNI is 7,170 Wh/m2 and an integrated solar combined cycle power plant exists on the premises. This paper discusses the design features of the main components of the new plant. Those features include a north field design, a 7.22-m2 single-sheet heliostat design, a cavity receiver to improve receiver efficiency by reducing radiative and convective losses, temperature-based particle flow regulation within the receiver, six hours of full-load thermal energy storage, with the tanks integrated into the tower structure and made of cost-effective masonry material, a shell-and-tube particle-to-air heat exchanger, a 45% efficiency recuperated intercooled gas turbine, and a high-temperature bucket elevator. The heliostat field was optimized using SolarPILOT. Results show that 1,302 heliostats are needed. The aperture area was found to be approximately 5.7 m2, while the total illuminated receiver surface area is about 16.8 m2. This design was found to be capable of achieving the particle temperature rise of 416°C, which is necessary to allow the turbine to rely entirely on the solar field to bring the temperature of air to the firing temperature of the turbine, thereby eliminating the need for fuel consumption except for back-up and for assistance at off-design conditions.


2021 ◽  
Vol 13 (15) ◽  
pp. 8421
Author(s):  
Yuan Gao ◽  
Jiandong Huang ◽  
Meng Li ◽  
Zhongran Dai ◽  
Rongli Jiang ◽  
...  

Uranium mining waste causes serious radiation-related health and environmental problems. This has encouraged efforts toward U(VI) removal with low cost and high efficiency. Typical uranium adsorbents, such as polymers, geopolymers, zeolites, and MOFs, and their associated high costs limit their practical applications. In this regard, this work found that the natural combusted coal gangue (CCG) could be a potential precursor of cheap sorbents to eliminate U(VI). The removal efficiency was modulated by chemical activation under acid and alkaline conditions, obtaining HCG (CCG activated with HCl) and KCG (CCG activated with KOH), respectively. The detailed structural analysis uncovered that those natural mineral substances, including quartz and kaolinite, were the main components in CCG and HCG. One of the key findings was that kalsilite formed in KCG under a mild synthetic condition can conspicuous enhance the affinity towards U(VI). The best equilibrium adsorption capacity with KCG was observed to be 140 mg/g under pH 6 within 120 min, following a pseudo-second-order kinetic model. To understand the improved adsorption performance, an adsorption mechanism was proposed by evaluating the pH of uranyl solutions, adsorbent dosage, as well as contact time. Combining with the structural analysis, this revealed that the uranyl adsorption process was mainly governed by chemisorption. This study gave rise to a utilization approach for CCG to obtain cost-effective adsorbents and paved a novel way towards eliminating uranium by a waste control by waste strategy.


Author(s):  
Christian L. Vandervort ◽  
Mohammed R. Bary ◽  
Larry E. Stoddard ◽  
Steven T. Higgins

The Externally-Fired Combined Cycle (EFCC) is an attractive emerging technology for powering high efficiency combined gas and steam turbine cycles with coal or other ash bearing fuels. The key near-term market for the EFCC is likely to be repowering of existing coal fueled power generation units. Repowering with an EFCC system offers utilities the ability to improve efficiency of existing plants by 25 to 60 percent, while doubling generating capacity. Repowering can be accomplished at a capital cost half that of a new facility of similar capacity. Furthermore, the EFCC concept does not require complex chemical processes, and is therefore very compatible with existing utility operating experience. In the EFCC, the heat input to the gas turbine is supplied indirectly through a ceramic heat exchanger. The heat exchanger, coupled with an atmospheric coal combustor and auxiliary components, replaces the conventional gas turbine combustor. Addition of a steam bottoming plant and exhaust cleanup system completes the combined cycle. A conceptual design has been developed for EFCC repowering of an existing reference plant which operates with a 48 MW steam turbine at a net plant efficiency of 25 percent. The repowered plant design uses a General Electric LM6000 gas turbine package in the EFCC power island. Topping the existing steam plant with the coal fueled EFCC improves efficiency to nearly 40 percent. The capital cost of this upgrade is 1,090/kW. When combined with the high efficiency, the low cost of coal, and low operation and maintenance costs, the resulting cost of electricity is competitive for base load generation.


Author(s):  
Prashanth N.A ◽  
P Sujatha

<p>Amongst all renewable energy generation sources, wind power exhibits fastest growth rate. The increasing number of wind farm installations worldwide demand low maintenance, cost and failure rates with high efficiency. Determining the optimal drive train configuration amongst various configurations available for wind turbines is a challenge. In this paper commonly used, doubly fed induction generator with single stage gear box (GDFIG), doubly fed induction generator with multi stage gear box (DFIG) and the direct-drive permanent-magnet generator (DDPMG) are compared. Modelling of wind turbine with efficiency computations is presented. Considering common wind turbine parameters, performance of GDFIG, DFIG and DDPMG is compared through an experimental study. Considering a reference 5 MW variable speed wind turbine, efficiency of DDPMG is 96% when compared to 93.58%, 93.12% for DFIG and GDFIG. The experimental results presented prove that the DDPMG is a preferable solution considering low cost and high efficiency.</p>


Author(s):  
Kenneth M. Armijo ◽  
Matthew D. Carlson ◽  
Dwight S. Dorsey ◽  
Joshua M. Christian ◽  
Craig S. Turchi

Abstract Nitrate molten salt concentrating solar power (CSP) systems are currently deployed globally and are considered state-of the art heat transfer fluids (HTFs) for present day high-temperature operation. Although slightly higher limits may be possible with molten salt, to fully realize SunShot efficiency goals of $15/kWhth HTFs and an LCOE of 6¢/kWh, HTF technologies working at higher temperatures (e.g., 650 °C to 750 °C) will require an alternative to molten salts, such as with alkali metal systems. This investigation explores the development of a 2.0 MWth sodium receiver system that employs a sodium receiver as the HTF, as well as with a ternary chloride (20%NaCl/40%MgCl/40%KCl by mol wt.%) salt as a thermal energy storage (TES) medium to facilitate a 6-hr. storage duration. A sodium-to-salt heat exchanger model as well as a salt-to-sCO2 primary heat exchanger model are employed and evaluated in this investigation. A thermodynamic system design model was developed using Engineering Equation Solver (EES) where state properties were calculated at inlets and outlets along both hot and cold legs of the pilot-scale plant. This investigation assesses receiver performance as well as system efficiency studies for the pump and system operational ranges. Results found that high efficiency sodium receivers were found to have higher heat transfer coefficients and required far less spreading of incident flux. The system performance model results suggest that for a pump speed of 2400 RPM, respective hot and cold pump TDH values were determined to be 260.1–307 ft. and 260.1–307 ft for pump flow rates of 90–120 GPM.


2019 ◽  
Vol 31 (7) ◽  
pp. 1230-1256
Author(s):  
Ali Mostafaeipour ◽  
Mostafa Rezaei ◽  
Mehdi Jahangiri ◽  
Mojtaba Qolipour

In this study, feasibility of a new wind power generation system for urban application in Hormozgan Province of Iran is investigated. The wind turbine system in this study is a novel, aesthetically pleasing, noiseless, pollution-free, potentially cost-effective, and high efficiency design called tree-shaped wind turbine (TSWT). Techno-economic evaluation is performed on eight urban areas in the province using the software HOMER. Multi-criteria decision making approaches are used to prioritize the areas in terms of the best location for installing such a new system. The results of techno-economic analysis examining a wind power system consisting of 25 TSWTs show that the most electricity production would occur for Jask city which is 529,450 kWh/yr. Also, the least amount of electricity which is 339,275 kWh/yr belongs to Bandar Abbas. Considering the most important criteria including electricity production, levelized cost of electricity, population, land price, environmental impact, and frequency of natural disasters, data envelopment analysis, and the fuzzy technique for order of preference by similarity to ideal solution are employed to rank the cities. The results are validated by two different methods. Finally, it is suggested that Sirik is the best location for using the aforementioned wind turbine.


2020 ◽  
Vol 1 (4) ◽  
pp. 658-665
Author(s):  
Thomas Rieks Andersen ◽  
Anne Therese Weyhe ◽  
Qiang Tao ◽  
Feng Zhao ◽  
Ran Qin ◽  
...  

Novel acceptor enhances the industrial readiness of solution based organic solar cells for low-cost electricity production.


2019 ◽  
Vol 795 ◽  
pp. 116-122
Author(s):  
Peng Yang Duan ◽  
Dong Xing Wang ◽  
Guo Yan Zhou ◽  
Shan Tung Tu

As the key component of the high temperature gas cooled reactor (HTGR), the performance of the plate fin heat exchanger determines the working efficiency and life of the HTGR. Although the plate-fin structure has lots of advantages such as high efficiency, compact structure, low manufacturing cost, its application will be affected by the vacuum brazing technology and harsh conditions, like high temperature and high pressure. In the practical application of plate-fin heat exchanger, the process of "splitting" between the fin and the diaphragm is very similar to that of the adhesive joint and the delamination of the composite. In the present study, a T-type specimen was designed for the the peel testing of brazed joints. Five kinds of specimens were designed based on the difference between the weld gap and the thickness of the sample base material. The tests were carried out under 450°C and 650°C at five kinds of loading rates, respectively. The peel force-displacement curves of standard samples were obtained . The maximum peel strength and average peel strength were calculated. In addition, the influence of base metal thickness, brazing gap, loading rate and test temperature on the maximum peel strength were analyzed by controlling variable method. Keywords: brazing joint; T-type peel test


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