Increase In Maximum Power Output Research Articles

Integrated photoelectrochemical energy storage cells prepared by benchtop ion soft landing.

The exceptional photochromic and redox properties of polyoxometalate anions, PW12O403−, have been exploited to develop an integrated photoelectrochemical energy storage cell for conversion and storage of solar energy. Elimination of strongly coordinating cations using benchtop ion soft landing leads to a ∼370% increase in the maximum power output of the device. Additionally, the photocathode displayed a pronounced color change from clear to blue upon irradiation, which warrants the potential application of the IPES cell in advanced smart windows and photochromic lenses.

Simulation and Experimental Verification of Electrical Power Output of a Microcontroller Based Solar Tracking Photovoltaic Module

The study evaluated the performance of a microcontroller based solar tracking PV system. The system utilized a stepper motor, two light dependent resistors and a worm gear to intelligently control the rotation of the photovoltaic modules such that it automatically provides the best alignment of the solar panel with the sun for maximum power output. The performance of the PV system was evaluated through simulation and experiment. The effect of different levels of solar irradiance and cell temperature was investigated on the power output of the solar tracking PV system. An increase in maximum power output (Pmax, m), actual light generated current (Ipv) and actual short circuit current (Isc) has been observed with the increase in solar irradiance. With the decreasing cell temperature, the power produced decreases. The percentage relative error between the optimum simulated and the experimental values for Pmax and Ipv was found below 5%, indicating that the simulation model found good agreement with the experimental values. The results are expected to provide insights into the interaction between weather data (irradiance and temperature) and PV module power output during conversion of solar energy into electricity.

Agri‐food waste valorisation

Agri‐food waste valorisation

ANALYZING THE RELATIONSHIP BETWEEN ANAEROBIC PERFORMANCE WITH ISCHEMIC PRECONDITIONING (IP) APPLICATION

The purpose of this study is to analyze the effects on recovery and anaerobic resistance when ischemic preconditioning is applied to the lower extremities of athletes. 12 male volunteers participated in this study with average age of 21.58±1.52 years. After all details of this study were explained to participants and approvals were collected, rast anaerobic power test was applied on consecutive days and blood lactate levels were measured. For the data analysis, researchers applied the Wilcoxon Signed Ranks test among a parametric test to evaluate pre- and post- ischemia/reperfusion rast test results. Additionally, a repetitive Friedman test analysis was used for analyzing lactic acid parameters. Additionally, a repetitive Friedman test analysis was used for analyzing lactic acid parameters. The significance level for the test results was determined as p<0.05, and values below this level were evaluated as statistically significant. When rast anaerobic power test results before and after the ischemia-reperfusion application were considered, it was seen that there was positive decrease in the fatigue index value, a positive increase in maximum power output and average power values, and that this had statistically significant results (p<0.05). Additionally, analysis results showed that when temporal level effects of ischemic preconditioning on lactic acid was analyzed, there was no difference on blood lactate values. One cycle of ischemia and reperfusion application showed statistically positive advancement for anaerobic power parameters. In this sense, it can be stated that ischemic preconditioning application increased anaerobic resistance in athletes. Article visualizations:

Enhanced oxytetracycline removal coupling with increased power generation using a self-sustained photo-bioelectrochemical fuel cell

Photo-bioelectrochemical fuel cell (PBFC) represents a promising technology for enhancing removal of antibiotic pollutants while simultaneously sustainable transformation of organic wastes and solar energy into electricity. In this study, simultaneous antibiotic removal and bioelectricity generation were investigated in a PBFC with daily light/dark cycle using oxytetracycline (OTC) as a model compound of antibiotic. The specific OTC removal rate increased by 61% at an external resistance of 50 Ω compared to that in the open-circuit control, which was attributed to bioelectrochemically enhanced co-metabolic degradation in the presence of the bioanode. The OTC removal was obviously accelerated during illumination of cathode in contrast with a dark cathode due to the higher driving force for anodic bioelectrochemical reaction by using photosynthetic oxygen as cathodic electron acceptor during illumination than that using nitrate in dark. The bioelectrocatalytic activity of anodic biofilm was continuously enhanced even at an initial OTC concentration of up to 50 mg L−1. The degradation products of OTC can function as mediators to facilitate the electron transfer from bacteria to the anode, resulting in 1.2, 1.76 and 1.8 fold increase in maximum power output when 10, 30 and 50 mg L−1 OTC was fed to the bioanode, compared to the OTC-free bioanode, respectively. The OTC feeding selective enriched OTC-tolerant bacterial community capable of degrading complex organic compounds and producing electricity. The occurrence of ARGs during bioelectrochemical degradation of OTC was affected more greatly by the succession of the anodic bacterial community than the initial OTC concentration.

Optical and Electrical Modeling of Dye Sensitized Solar Cell: Influence of the Overlap Distance Between TiO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; Particles

Dye sensitized solar cells (DSSC) are used for photovoltaic applications. The paper presents a methodology for optical and electrical modeling of dye-sensitized solar cells (DSSCs). In order to take into account the influence of the overlap distance between two TiO2 particles on the cell an optoelectronic model for DSSC is presented in this paper. From the radiative transfer equation and Mie theory, the optical generation rate of cell is deduced. Coupling the output of the optical model (the dye absorption rate) to an electrical model allows determination of short-circuit current density and maximum power output. Due to our model, the dependence effects of the overlap distance upon the porosity, the optical generation rate, the short circuit current density and the maximum power output are evidenced. Thus, we see that when the overlap distance increases the porosity decreases. In addition, when the overlap distance increases, the absorption rate decreases when the overlap distance is greater than TiO2 radius divide by 5. Moreover, we see that when the overlap distance is lower than the TiO2 radius divided by 5, the short circuit current density and the maximum power output increase. However, when the overlap distance is higher than TiO2 radius divided by 5 they decrease. Thus, according to the model, we see that the optimal overlap distance is equal to TiO2 radius divide by 5. Our results agree with those found in the literature.

Analyzing the Performance of a Dual Loop Organic Rankine Cycle System for Waste Heat Recovery of a Heavy-Duty Compressed Natural Gas Engine

A dual loop organic Rankine cycle (DORC) system is designed to recover waste heat from a heavy-duty compressed natural gas engine (CNGE), and the performance of the DORC–CNGE combined system is simulated and discussed. The DORC system includes high-temperature (HT) and low-temperature (LT) cycles. The HT cycle recovers energy from the exhaust gas emitted by the engine, whereas the LT cycle recovers energy from intake air, engine coolant, and the HT cycle working fluid in the preheater. The mathematical model of the system is established based on the first and second laws of thermodynamics. The characteristics of waste heat energy from the CNGE are calculated according to engine test data under various operating conditions. Moreover, the performance of the DORC–CNGE combined system is simulated and analyzed using R245fa as the working fluid. Results show that the maximum net power output and the maximum thermal efficiency of the DORC system are 29.37 kW and 10.81%, respectively, under the rated power output condition of the engine. Compared with the original CNG engine, the maximum power output increase ratio and the maximum brake specific fuel consumption improvement ratio are 33.73% and 25%, respectively, in the DORC–CNGE combined system.

Performance Analysis of an Otto Engine with Ethanol and Gasoline Fuels

Energy conservation and its efficient use are nowadays a major issue. The evident reduction in oil reserves combined with the increase in its price, as well as the need for ‘cleaner’ fuels, have led in the past years to an increasing interest and research in the field of alternative fuels for spark ignition engines propulsion. Also, there are interesting to increase the technical focus on conventional cycles for making them more optimum in terms of performance. In this study, a comparative performance analysis and optimisation have been performed for irreversible Otto cycle with ethanol, methanol and gasoline fuels. The results show that the maximum power output, the working range of the cycle, the optimal power output corresponding to maximum thermal efficiency, the optimal thermal efficiency corresponding to maximum power output increase, the compression ratio at the maximum power output and the compression ratio at the maximum thermal efficiency when ethanol-engine operation is changed to gasoline-engine operation. The results obtained in this work can help us to understand how the power output and thermal efficiency are influenced by ethanol and gasoline fuels in an Otto engine.

The effects of heat transfer on the exergy efficiency of an air-standard otto cycle

The exergy analysis of an air-standard Otto cycle with heat transfer loss is analyzed by using finite-time thermodynamics. The results showed that the heat transfer loss is responsible for a significant destruction of exergy. It is also shown that exergy efficiency and maximum power output increase with decreasing heat transfer loss. The results obtained in this paper may provide useful information for the maximum work available.

Enhanced ASC Performance at 600{degree sign}C by Ceria Barrier Layer Optimisation

Reduction of the SOFC operating temperature to 600{degree sign}C is an effective approach for reducing the costs of applied materials and increasing the lifetime of SOFC systems. The anode-supported cell design (ASC) with thin electrolyte is a promising configuration for operation at this temperature. This paper deals with the ASC performance improvement at 600oC by optimisation of the ceria barrier layer that is placed between the La0.6Sr0.4CoO3-δ cathode and the zirconia electrolyte to prevent the formation of resistive secondary phases. Conventional screen printing has been used for the deposition of the ceria barrier layer. The improved screen printed ceria layer results in an increase in maximum power output of the anode supprted cell from 260 to 580 mW/cm2 at an operating temperature of 600oC. The performance improvement was mainly caused by a significant reduction of ohmic losses.

Performance analysis of air-standard Diesel cycle using an alternative irreversible heat transfer approach

This study presents the investigation of air-standard Diesel cycle under irreversible heat transfer conditions. The effects of various engine parameters are presented. An alternative approach is used to evaluate net power output and cycle thermal efficiency from more realistic parameters such as air–fuel ratio, fuel mass flow rate, intake temperature, engine design parameters, etc. It is shown that for a given fuel flow rate, thermal efficiency and maximum power output increase with decreasing air–fuel ratio. Also, for a given air–fuel ratio, the maximum power output increases with increasing fuel rate. However, the effect of the thermal efficiency is limited.

Analysis of chimney height for solar chimney power plant

Current in solar chimney power plant that drives turbine generators to generate electricity is driven by buoyancy resulting from higher temperature than the surroundings at different heights. In this paper, the maximum chimney height for convection avoiding negative buoyancy at the latter chimney and the optimal chimney height for maximum power output are presented and analyzed using a theoretical model validated with the measurements of the only one prototype in Manzanares. The results based on the Manzanares prototype show that as standard lapse rate of atmospheric temperature is used, the maximum power output of 102.2 kW is obtained for the optimal chimney height of 615 m, which is lower than the maximum chimney height with a power output of 92.3 kW. Sensitivity analyses are also performed to examine the influence of various lapse rates of atmospheric temperatures and collector radii on maximum height of chimney. The results show that maximum height gradually increases with the lapse rate increasing and go to infinity at a value of around 0.0098 K m −1, and that the maximum height for convection and optimal height for maximum power output increase with larger collector radius.

Effects of 0.28–2.80 MeV proton irradiation on GaInP/GaAs/Ge triple-junction solar cells for space use

GaInP/GaAs/Ge triple-junction solar cells were irradiated with 0.28, 0.62 and 2.80MeV protons with fluences ranging from 1×1010cm−2 to 1×1013cm−2. Their performance degradation is analyzed using current–voltage characteristics and spectral response measurements. The degradation rates of the short circuit current, open circuit voltage, and maximum power output increase with fluence, but decrease with increasing proton energy. It was also observed that the spectral response of the GaAs middle cell degrades more significantly than that of the GaInP top cell.

Behavioral Intervention, Exercise, and Nutrition Education to Improve Health and Fitness (BENEfit) in Adolescents With Mobility Impairment Due to Spinal Cord Dysfunction

Background/Objective: Determine the effects of a nutrition education and exercise intervention on the health and fitness of adolescents with mobility impairment due to spinal cord dysfunction from myelomeningocele and spinal cord injury. Subjects participated in a 16-week intervention consisting of a behavioral approach to lifestyle change, exercise, and nutrition education to improve fitness (BENEfit) program. Participants were given a schedule of aerobic and strengthening exercises and attended nutrition education and behavior modification sessions every other week along with their parent(s).Subjects: Twenty adolescents (aged 11–18 years, mean 15.4 ± 2.2 years) with spinal cord dysfunction.Methods: Subjects were tested immediately prior to starting and upon completion of the program. Aerobic fitness was measured using a ramp protocol with an arm ergometer. Heart rate and oxygen uptake were measured. Values at anaerobic threshold and maximum oxygen uptake were recorded. Peak isokinetic arm and shoulder strength were determined with a dynamometer. Body composition was estimated with dual–energy x–ray absorptiometry. Serum chemistry included measures of cholesterol, high–density lipoprotein, low-density lipoprotein, and triglycerides.Results: Fourteen individuals completed all testing sessions. There was no significant overall change in weight, body mass index, body mass index z–scores, or serum chemistry. Overall, there was a significant increase in whole body lean tissue without a concomitant increase in whole body fat. Fitness measures revealed a significant increase in maximum power output, work efficiency as measured by the amount of power output produced aerobically, and resting oxygen uptake. Strength measurements revealed a significant increase in shoulder extension strength and atrend towards increased shoulder flexion strength. There were no significant changes in high–density lipoprotein, low–density lipoprotein, total cholesterol, or triglycerides.Conclusions: The BENEfit program shows promise as a method for improving the health and fitness of adolescents with mobility impairments who are at high risk for obesity and obesity-related health conditions.

Enhanced infrared photovoltaic efficiency in PbS nanocrystal/semiconducting polymer composites: 600-fold increase in maximum power output via control of the ligand barrier

We report a comparison of photoconductive performance of PbS nanocrystal/polymer composite devices containing either oleic acid-capped or octylamine capped nanocrystals (NCs). The octylamine-capped NCs allow over two orders of magnitude more photocurrent under −1V bias; they also show an infrared photovoltaic response, while devices using oleic acid-capped NCs do not. Further improvement in the photovoltaic performance of films made with octylamine-capped NCs occurs upon thermally annealing the composite layer at 220 °C for 1 h. The procedure leads to a 200-fold increase in short circuit current, a 600-fold increase in maximum power output, and an order of magnitude faster response time.

Targeting improved DMFC performance

Improved DMFC performance through reduction in the extent of methanol crossover in the polymer electrolyte membrane is described. Introduction of a thin barrier layer of polybenzimidazole (PBI) at the Nafion ®117 surface by screen printing is shown to reduce methanol permeability whilst maintaining proton conductivity at a level comparable to that of the parent material. Experimental trials using these Nafion ®117/PBI composite films show improved DMFC performance; an increased working current density range of 42% combined with an increase in maximum power output of 46% over that of the parent material.