Power Generation Device Research Articles

Fe-Al-Si Thermoelectric (FAST) Materials and Modules: Diffusion Couple and Machine-Learning-Assisted Materials Development.

To lower the introduction and maintenance costs of autonomous power supplies for driving Internet-of-things (IoT) devices, we have developed low-cost Fe-Al-Si-based thermoelectric (FAST) materials and power generation modules. Our development approach combines computational science, experiments, mapping measurements, and machine learning (ML). FAST materials have a good balance of mechanical properties and excellent chemical stability, superior to that of conventional Bi-Te-based materials. However, it remains challenging to enhance the power factor (PF) and lower the thermal conductivity of FAST materials to develop reliable power generation devices. This forum paper describes the current status of materials development based on experiments and ML with limited data, together with power generation module fabrication related to FAST materials with a view to commercialization. Combining bulk combinatorial methods with diffusion couple and mapping measurements could accelerate the search to enhance PF for FAST materials. We report that ML prediction is a powerful tool for finding unexpected off-stoichiometric compositions of the Fe-Al-Si system and dopant concentrations of a fourth element to enhance the PF, i.e., Co substitution for Fe atoms in FAST materials.

Influence and Simulation of Pipeline in Floating Wave Power Generation System

With the gradual decrease of land resources, people pay more and more attention to the development of marine resources, and the use of marine wave energy has become the focus of people. In this paper, the pipeline parameters and pipeline model of the floating power generation device are set up. The comprehensive simulation of the hydraulic system is established by AMESim software. Under the condition of ensuring the normal results of the simulation model, the simulation model is solved by the solver to obtain the pressure fluctuation in the pipeline. The influence of inner diameter and length of pipeline on pressure fluctuation is analyzed. At the same time, through the feedback of pipeline pressure and the actual situation analysis, the feasible suggestions are given, which has certain reference significance for the design of hydraulic pipeline and provides theoretical support for the actual large wave power generation.

Performance analysis of a new type of rainwater power generation device based on piezoelectric effect

In this paper, the water catchment device is combined with the piezoelectric cantilever beam to gather raindrops into a larger rainball to improve the power generation efficiency of the system. This makes rainwater power generation more feasible. The results show that when the rainfall intensity is constant, the output voltage of the power generation system increases significantly as the size of the rainwater converging device increases. With the same size of rainwater converging device, as the rainfall intensity increases, the power generation effect is also significantly improved, thus demonstrating the feasibility of the new rainwater power generation device.

Optimal Design and Performance Analysis of Thermoelectric Power Generation Device Based on Multi‐Objective Genetic Algorithm

AbstractThe combined use of flue gas waste heat resources and thermoelectric generators (TEGs) is considered to be a relatively reliable method to generate electricity. The focus of this study is on the optimization and improvement of the hot‐end heat collection pipe. This paper aims to increase the temperature difference between hot and cold ends of TEG and enhance uniformity of temperature distribution, thereby improving the output power of the TEG system. To balance the temperature difference between the cold and hot ends of the TEG, the pressure drop from the inlet to the outlet and the mass of TEG hot end pipes, a finite element simulation model is constructed. Meanwhile, a multi‐objective genetic algorithm is applied to optimize the structure of four dimensions: fin bottom length, fin height, fin thickness, and outlet diameter. Three optimization objectives, namely, average temperature difference, total pressure drop from inlet to outlet, and pipeline mass are globally optimized to determine the best size, based on which the accuracy of the simulation model is verified by conducting experiments.

Is it possible for a photovoltaic-thermoelectric device to generate electricity at night?

Photovoltaic-thermoelectric (PV-TE) conversion is a promising method for power generation, which converts solar power into electricity using the photovoltaic (PV) effect of solar cells and simultaneously generates electricity by the Seebeck effect of the thermoelectric (TE) device based on the waste heat of solar cells. Here, the power generation of the PV-TE device at night is experimentally demonstrated using radiative cooling that harnesses the cold of the universe directly. The PV-TE device is constructed by attaching a TE device on the bottom of the glass-covered PV module, with a heat sink stuck on the opposite side of the TE device. The open-circuit voltage of the TE device integrated into the PV-TE device was measured to be approximately 9 mV, indicating that the PV-TE device can definitely generate electricity from the darkness. Moreover, a new configuration of the PV-TE device for continuous power generation in the day and night is conceptually proposed for further consideration. In summary, this work proves the possibility of the PV-TE device for nighttime power generation, which could provide an alternative pathway for a wide range of nighttime and all-day power-consumed applications, such as lower power sensors and monitors. • Nighttime power generation of the PV-TE device was experimentally demonstrated. • An average output voltage of the PV-TE device was measured as 9 mV in night. • A new configuration of the PV-TE device for continuous power generation is proposed. • This work provides an alternative pathway for nighttime and all-day applications.

Thermoelectric materials with crystal-amorphicity duality induced by large atomic size mismatch

Summary Discovering novel materials and attaining higher performance are the eternal pursuit of thermoelectric materials research. Here, we report a material series, (Cu1−xAgx)2(Te1−ySy) (0.16 ≤ x ≤ 0.24, 0.16 ≤ y ≤ 0.24), which adopts a complex orthorhombic structure differing from any known crystal structure of (Cu/Ag)2(S/Te). This material series is featured by the crystal-amorphicity duality induced by the large anionic size mismatch: a crystalline sublattice of highly size-mismatched anions Te/S coexists with an amorphous-like sublattice of cations Cu/Ag. In the context of structure-property correlation, the crystal-amorphicity duality gave rise to not only interesting electrical properties but also exceptionally low lattice thermal conductivities from 300 to 1,000 K. A state-of-the-art figure of merit zT of 2.0 is obtained in the x = y = 0.22 sample at 1,000 K. These results give insights into crystal-amorphicity duality as a paradigm-shifting materials design approach to develop high-performance thermoelectric materials.

Operando optical studies of solid oxide fuel cells operating on CO and simulated syngas fuels

Solid oxide fuel cells (SOFCs) are attractive devices for combined power and heat generation because they can operate with a variety of fuels. Syngas (CO + H2) is particularly attractive but many questions remain about its behavior on SOFC anodes including the relative oxidation efficiencies of CO and H2 and tendency to form carbon deposits. In this report, operando spectroelectrochemical measurements, including infrared emission spectroscopy, near infrared thermal imaging, and vibrational Raman scattering, combined with spectrochronopotentiometry, are performed using anode-supported SOFCs operating with simulated syngas at 800 °C. Results quantify the fate of syngas over Ni-YSZ anodes in SOFCs related to their performance. SOFCs operating with simulated syngas mixtures are compared with those for H2 and CO used separately. Thermal imaging shows more SOFC anode heating for H2-rich syngas than for operating on CO or H2 alone. We attribute this result to carbon gasification by water that is produced by H2 oxidation. Raman spectra together with spectrochronopotentiometry experiments illustrate that carbon is not observed on the anode surface at 800 °C – although it is at 750 °C and 700 °C – yet carbon is likely present in the spectroscopically inaccessible, electrochemically active region at the electrolyte-electrode interface.

Design of Duck Wave Power Generation Device Based on Wave Energy

The study of wave power generation is more and more popular in modern science and technology for the new renewable energy, in recent years. Designing wave power generation devices with high conversion efficiency and stability, and improving the technical level for commercialization are both scientifically interesting and potentially useful. Here we achieve the stability of wave generation equipment by establishing one nodding duck energy conversion system in a wave tank. Equipped with ultrasonic distance sensor, combining screw slide and stepper motor as draft self-regulation feedback system, our device is always in the best working performance under the single-chip microcomputer STM32 auto-measuring system. The good conversion efficiency performance can be 43%. The ARDUINO module and the Labview host computer interface are equipped to real-time visualize and characterize the parameters of the device and calculate the optimal power generation efficiency. Our designed device can resist damage validly with high conversion efficiency and stability.

Investigation on Runaway Process in Power Generation Device: Tubular Turbine Based on IB-LBM Method

The immersed boundary lattice Boltzmann method (IB-LBM) was applied to numerically simulate the runaway process of tubular turbines with the influence of the free surface of upper and lower reservoirs. First, the accuracy of the IB-LBM method was verified, and then the external performance and internal flow characteristics of units during runaway process were studied. The results show that the gravity causes uneven pressure distribution at inlet of the turbine with considering the influence of the free surface of the reservoirs, resulting in complicated flow pattern, which cannot be ignored in the study. In the course of runaway, low-pressure area of draft tube changes periodically with a certain degree of cavitation occurring on pressure and suction surface of the blades, which threatens the overall operation stability of the unit.

Heat recirculation and heat losses in porous micro-combustors: Effects of wall and porous media properties and combustor dimensions

The micro-combustor is a key component of most combustion-based micro power generation devices. Porous micro-combustors stand as a potential promising solution able to sustain reactions under a wider range of conditions. Multiple heat transfer modes co-exist and are closely coupled in porous micro-combustors, and therefore the primary objective of the present study is to analyze various heat fluxes occurring in porous micro-combustors in a quantitative manner in order to reveal their relative importance and provide clues for better design and operation of such devices. Numerical simulations of premixed combustion of H2/air in porous combustors with the combustor heights from 1.0 mm to 2.0 mm are carried out. By quantifying heat recirculation and heat losses in the preheat zone and the reaction zone, respectively, the effects of the wall thermal conductivity and the porous media properties (thermal conductivity and porosity) on the flame temperature are discussed. Comparing the results of different combustor heights shows that the smaller porous micro-combustor has a higher proportion of heat recirculation relative to heat losses. The flame temperature is found to be inversely related to the ratio of total heat losses to total heat recirculation. The methodology developed in this study could be easily applied to other micro-combustor configurations with or without the porous media with necessary adaptions.

Research on Algorithm Fusion for the Control of a Roots-Type Waste Heat Power Generation System

At present, the recovery of low-quality waste heat is a major problem in energy utilization. To solve this problem and improve energy efficiency, this research group designed a low-quality waste heat power generation device with a roots-type power machine as the core component. However, the power generation device produces a large hysteresis in power generation regulation. While the hardware can be improved, the design of the measurement and control system is also critical. In view of the problems existing in low-quality waste heat power generation devices, this research group introduced an internal model controller into the control system and designed an internal model controller and filter through the analysis of each module. In addition, to improve the performance of the controller, this research group applied the deep learning method to optimize the control system and used the prediction function of the deep learning method to further improve the stability of the device. The simulation and experimental results show that the control strategy can make this device for the recovery of low-quality waste heat respond quickly to fluctuations in the gas source and improve the hysteresis problem.

Integration of heat recirculating microreactors with thermoelectric modules for power generation: a comparative study using CFD

CFD analysis of the trade-off between the catalytic microreactor and thermoelectric generator can optimize the performance of the integrated device for power generation.

Pine-like concentrating power generation device

Today, when energy problems are increasingly prominent, the development and utilization of solar energy has become the focus of achieving sustainable energy development. However, due to the dispersion of solar radiation energy and atmospheric absorption, the radiation intensity directly reaching the surface of the earth is relatively weak. The existing linear Fresnel concentrators in engineering are huge in size and have low concentration ratios. In order to increase the concentration ratio of the CSP device, the pine-like CSP device combines the advantages of both the CSP device and the tree-like structure. It has the advantages of low cost, high efficiency, and small footprint, which will solve the problem. This will be a useful attempt to solve the problem of urban solar energy utilization and give new ideas to solve the problem.

Research on evaluation method of energy supply reliability of regional energy Internet

This paper studies the reliability evaluation technology of regional energy Internet and represents a reliability evaluation method considering the optimal load reduction strategy. The application scenario of regional Energy Internet with power system as the core is built. The specific form is that multiple Integrated Energy systems are connected to the superior distribution network through the tie line. The reliability evaluation index system of power system and regional energy Internet is introduced. Based on the modelling of components in the regional energy Internet application scenario in this paper, the operation model and two-state Markov model are mainly established for the renewable energy power generation devices, energy coupling devices and energy storage devices in IES. The optimal load reduction models based on load classification are established for the faults of distribution network lines and the faults of IES internal components connected to the distribution network in regional energy Internet respectively. Through the construction of different application scenarios, the load reduction situation under different faults and different component parameters is analysed, and the corresponding reliability index calculation and result analysis are carried out.

Development of a Structural Control and Power Generation Device Employing an Inerter Mechanism for Floating Offshore Wind Turbines

Development of a Structural Control and Power Generation Device Employing an Inerter Mechanism for Floating Offshore Wind Turbines

Influence of Buoy Size on Accelerated Wave Power Generation Device

This paper proposed a pulley-buoy accelerated wave energy linear power generation system, and the feasibility and effectiveness of this system were verified through experimental research. Compared with the traditional wave energy power generation system with three-stage energy conversion links, the pulley-buoy accelerated wave energy linear power generation system omits the intermediate energy transfer and conversion link, and realizes the direct gain of electric energy from the buoy movement caused by wave, and by introducing the pulley combination, the movement speed of the buoy is enlarged, the power generation of the linear power generation system is increased, thereby the wave energy conversion efficiency of the system is improved. Under laboratory conditions, a small-size pulley-buoy accelerated wave energy linear power generation system prototype and a swing-plate wave-making system were built to explore the effects of different buoy sizes on the power generation performance of the system. The test results show that within the research scope of this paper, increasing the size of the buoy can effectively increase the wave energy conversion efficiency of the system and improve the power generation performance of the accelerated wave energy power generation system. The research results in this paper provide useful experience for the practical application and efficient operation of wave energy power generation systems.

Development of Geothermal Power Generation Device using Heat Conduction System and Class Practice on Renewable Energy

Development of Geothermal Power Generation Device using Heat Conduction System and Class Practice on Renewable Energy

Operation Verification of Battery Free Self-Sensing Wireless System by Magnetostrictive Vibration Power Generation Device

The IoT used in recent years often uses a button battery or the like, but it has disadvantages in terms of labor and cost of replacement. In addition, IoT applications include the detection and monitoring of abnormalities in rotating machinery. These systems are composed of sensors, wireless modules, and power supplies. There is a demerit in the wiring of the comparator point. Therefore, we are conducting research on vibration power generation to replace these batteries. In this research, speed is detected from the voltage generated by the vibration power generation device, and at the same time, wireless communication is performed using the generated power. This time, we constructed a self-sensing system that generates such self-power and detects and transmits the speed change of the target. Then, this operation was verified.

Development of a Structural Control and Power Generation Device Employing an Inerter Mechanism for Floating Offshore Wind Turbines

Development of a Structural Control and Power Generation Device Employing an Inerter Mechanism for Floating Offshore Wind Turbines

Electrokinetic effect and H2O2 boosting in synthetic graphene/α-FeOOH aerogel films for the generation of electricity

Novel catalytic α-FeOOH/graphene aerogel films for high performance hydrovoltaic power generation devices have been developed with an exceptionally high power density of 47 mW m−2 upon the addition of H2O2 to the saline solution.