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Solar power tower technology has strong potential among the other concentration solar power techniques for large power generation. Therefore, it is necessary to make a new and efficient power conversion system for utilizing the solar power tower system. In present research, a novel combined cycle is proposed to generate power for the application of the solar power tower. The pre‐compression configuration of the Brayton cycle is used as a topping cycle in which helium is taken as the working fluid. The transcritical CO2 cycle is used as bottoming cycle for using the waste heat. The proposed system is investigated based on exergy, energy, and exergoenvironmental point of view using computational technique engineering equation solver. Also, the parametric analysis is carried out to check the impact of the different variables on the system performance. It is concluded that the overall plant's optimized thermal and exergy efficiencies are obtained as 31.59% and 33.12%, respectively, at 800 °C optimum temperature of combined cycle and 850 W m−2 of direct normal irradiation and 2.278 of compressor pressure ratio. However, exergetic stability factor and exergoenvironmental impact index are observed as 0.5952 and 0.6801 respectively. The present proposed system performs better than the previous studies with fewer components. [ABSTRACT FROM AUTHOR]

Carbon‐free and safe power solutions, such as fast charging batteries for mid‐to‐large applications, are viable alternatives to address ever‐increasing energy demand while reducing environmental pollution. However, the self‐generated heat produced during the charge/discharge process severely hampers the performance, stability, and safety of fast charging batteries. Thus, a suitable working temperature range must be maintained to maximize efficiency. Well‐designed battery thermal management systems (BTMSs) can provide an appropriate temperature environment for maximizing battery performance with superior stability and safety. The objective of this study is to present a clear and detailed discussion on this ability of BTMSs, battery materials, and the effects of temperature on battery performance during rapid charging. Furthermore, battery modeling methods are highlighted, and the existing BTMSs are comprehensively reviewed and categorized according to their components and preparation processes. Additionally, the methods of cooling such systems based on phase change materials (PCMs), heat pipes, and thermoelectric elements, are explored. In addition, BTMSs based on air, liquids, and PCMs that undergo solid–liquid, liquid–gas, and solid–gas transitions are also discussed. [ABSTRACT FROM AUTHOR]

The objective of this study is the investigation of a cogeneration system for heating and electricity production, which is driven by solar dish concentrators. There is an organic Rankine cycle (ORC) driven by the solar field and produces electricity with its turbine and heating from its condenser. The solar field includes 100 m2 of solar dish concentrators with spiral absorber and an insulated storage tank of 4 m3 storage volume. The system is examined parametrically for different pressure levels in the turbine inlet and superheating degree. The system exergy efficiency is maximized for a superheating of 30 K and a maximum pressure equal to 70% of the toluene critical pressure. In this case, the system produces 12.41 kW electricity, 28.55 kW heating, while the energy efficiency is 51.20%, and the exergy efficiency is 20.69%. Moreover, the system is examined for a typical sunny day, and it is found that the electricity production is 125.6 kWh, the heating production 288.86 kWh, the energy efficiency 48.96%, and the exergy efficiency 19.77%. In the end, the simple payback period of the examined system is found at 6.28 years, which is a good value. [ABSTRACT FROM AUTHOR]

Supercapacitors are electrochemical devices that can store and restore electrical energy and are mostly used for powering dc or close‐to‐dc applications. As such they have not been explored enough for non‐dc circuits. In this study, we implement a band‐pass for frequency selectivity purposes and a relaxation oscillator for timing applications using a solid‐state carbon electric double‐layer capacitor. The expected behavior was observed for both circuits in the sub‐Hertz and tens of Hertz frequency ranges. This confirms the possibility of using the frequency‐dependent capacitive behavior of such devices in non‐conventional low frequency applications not related to dc energy storage but requiring large time constants. A band‐pass filter for frequency selectivity purposes and a relaxation oscillator for timing applications using a solid‐state carbon electric double‐layer capacitor (EDLC) is implemented. Specifically, in the band‐pass circuit, the device's capacitive behavior is clear with a resonance frequency centered at 130 Hz. Whereas from the relaxation oscillator circuit, the device performs well at frequencies below the Hertz up to 22 Hz. This highlights the possibility of using the frequency‐dependent capacitive behavior of EDLC for low frequency applications. [ABSTRACT FROM AUTHOR]