Thermoelectric Power Generation System Research Articles

Thermoelectric power generation system intelligent Runge Kutta control: A performance analysis using processor in loop testing

As an emerging source of clean electrical power, Thermoelectric generation (TEG) finds its applications in heat removal and electricity generation as an efficient improvement tool for thermal devices utilizing fossil fuels. TEG exhibits low power density and its temperature distribution is usually non-uniform over thermal conductive surfaces. Due to the non-uniformity of heat flow and loose surface contact, non-uniform temperature distribution (NTD) appears on TEG surfaces and the TEG control problem becomes complex, multi-solution, nonlinear, and highly sensitive to operating conditions. The bypass diode activation of TEG systems streamlines the power flow in a string of series-connected modules, generating multiple peak points. Classical techniques fail to address these issues of multiple maxima and lose efficiency. To solve this problem, a novel SI-based optimization algorithm, Runge Kutta Method (RUN), is applied as MPPT control. To gauge the performance of the proposed controller several distinct case studies are used, including varying temperatures gradient, NTD, 24-hour thermal profile stochastic temperature, and experimental verification. Additionally, MPPT rating analysis, economic assessment, and statistical studies are done for comparison with other state-of-the-art control techniques. The minimum tracking and settling times have been improved by RUN to 180 ms. For the additional hardware implementation, the maximum levelized cost of energy (LCOE) is about 0.16 $kWh1.07¥kWh. The power tracking efficiency of RUN can be above 99 % with energy harvest improvements of 6.3 %.

Enhanced Heat Transfer in Thermoelectric Generator Heat Exchanger for Sustainable Cold Chain Logistics: Entropy and Exergy Analysis

This study investigates the application of thermoelectric power generation devices in conjunction with cold chain logistics transport vehicles, focusing on their efficiency and performance. Our experimental results highlight the impact of thermoelectric module characteristics, such as thermal conductivity and the filling thickness of copper foam, on the energy utilization efficiency of the system. The specific experimental setup involved a simulated logistics cold chain transport vehicle exhaust waste heat recovery thermoelectric power generation system, consisting of a high-temperature exhaust heat exchanger channel and two side cooling water tanks. Thermoelectric modules (TEMs) were installed between the heat exchanger and the water tanks to use the temperature difference and convert heat energy into electrical energy. The analysis demonstrates that using high-performance thermoelectric modules with a lower thermal conductivity results in better utilization of the temperature difference for power generation. Additionally, the insertion of porous metal copper foam within the heat exchanger channel enhances convective heat transfer, leading to an improved performance. Furthermore, the study examines the concepts of exergy and entropy generation, providing insights into the system energy conversion processes and efficiency. Overall, this research offers valuable insights for optimizing the design and operation of thermoelectric generators in cold chain logistics transport vehicles to enhance energy utilization and sustainability.

Numerical Investigation of Performance Enhancement for Thermoelectric Generator System Optimization of HX Fin Shape

This paper presents a performance analysis and optimization of heat exchanger fin shapes in a thermoelectric power generation system for ship waste heat recovery. It proposes a new curved fin design aimed at enhancing heat transfer efficiency and maximizing thermoelectric power generation capacity. Numerical analysis and response surface methodology (RSM) focused on 225 parameters to identify the optimal fin shape. Computational analysis using CFX was conducted on the thermoelectric module system with curved fins. The methodology was verified by comparing and analyzing CFD and PIV experimental results for a curved fin. The paper comprehensively compares the fluid dynamics of curved fins and straight fins, highlighting how curved fins improve heat exchange by creating a tip leak vortex. The results demonstrate the superiority of the curved fin design in terms of heat transfer efficiency and net power generation over the conventional straight fin design.

Multi-scale CuS-rGO pyramidal photothermal structure for highly efficient solar-driven water evaporation and thermoelectric power generation

Integrated water evaporation and thermoelectric power generation system (IWETPGS) has been recognized to be a promising strategy for the utilization of solar energy. Herein, we developed a new type of IWETPGS with multi-scale pyramidal photothermal structures. They featured three-dimensional pyramidal structures with microscale gradient porous copper foams, as well as micro/nanoscale CuS nanowires and reduced graphene oxide (rGO) composite materials. They combined the merits of efficient multiple refraction and absorption of light, broad-spectrum absorption capabilities of rGO and high near-infrared extinction coefficient of CuS, as well as fast water transportation by gradient porous matrix. These photothermal structures induced a photothermal conversion efficiency of 97.6%. An IWETPGS integrating these structures with a thermoelectric generator (TEG) and microchannel heat sink was developed, and outstanding evaporation and output power performance were obtained simultaneously with an evaporation rate of 2.29 kg/m2h and maximum output power of 1.32 W/m2 under 1 sun illumination. Outdoor tests showed that an average daily water production of 12.1 kg/m2 and a maximum power generation of 5.55 W/m2 was obtained. This work provides a high-performance multi-scale CuS-rGO pyramidal photothermal structure to achieve freshwater and thermoelectric power co-generation, which provides potential opportunities for freshwater and electricity supply in remote areas.

Design and Power Generation Characteristics Analysis of a Self-adaptive Thermoelectric Power Generation System Based on LTspice

Design and Power Generation Characteristics Analysis of a Self-adaptive Thermoelectric Power Generation System Based on LTspice

Effects of Installing Different Types of Cooling Fins on the Cold Side of a Thermoelectric Power Generation Device on the Thermal Efficiency and Exergy Efficiency of Power Cable Surface Waste Heat Recovery.

This study investigates the thermal efficiency and exergy efficiency of a thermoelectric power generation device for recovering power cable surface waste heat. Numerical simulations are conducted to analyze the impact of different types of cooling fins on the system's performance. The results demonstrate that the installation of cooling fins improves heat transfer efficiency and enhances the thermoelectric power generation device's output power. Among the various fin designs, the system equipped with cooling fins with 17 teeth exhibits the highest performance. These findings highlight the importance of fin design in optimizing the system's thermal efficiency and exergy efficiency. This study provides valuable insights for the development and improvement of thermoelectric power generation systems for power cable surface waste heat recovery applications.

Photothermal and thermoelectric power generation performance based on bionic structure and composite nanofluids

Thermoelectric power generation (TEG) technology is a green energy utilization technology that is spread over a wide range of industrial fields. Based on the Seebeck effect, in order to provide a higher output voltage of the thermoelectric power generation, raising the temperature difference at both ends of the thermoelectric power generation is a very effective method. Fe3O4 particles were modified on the nanotube particles by co-precipitation method to produce novel composite magnetic FCNTs nanofluids. They have excellent paramagnetism under geomagnetic field and exhibit promising photothermal efficiency. The cooling scheme based on bionic structure and photothermal nanofluids were coupled to the TEG technology, and a TEG experimental platform was built. The temperature rises of photothermal nanofluids in the TEG system was studied. Effects of Reynolds number (Re=600–1200), light intensity (2 sun, 3 sun, 4 sun) and nanofluids concentration (50 ppm, 100 ppm, 150 ppm) on thermoelectric power generation were studied. Results showed that the capacity of the TEG can be strengthened by increasing mass fraction of nanofluids and light intensity. The maximum open circuit voltage of the system can reach 6.48 mV, and the max increase ratio is 25.06%.

Multiphysics Co-Simulation and Experimental Study of Deep-Sea Hydrothermal Energy Generation System

With the continuous deepening of research on seafloor hydrothermal observations, the demand for a sustainable power supply of observation equipment is increasingly urgent. A kind of device that utilizes the temperature difference near hydrothermal vents to provide power is studied. However, the frequent experiments required for in-depth research on this device contradict the rare opportunities for hydrothermal field experiments and the difficulty in laboratory replication. In response to the above difficulties, a multiphysics co-simulation of the deep-sea hydrothermal energy generation system is studied in this paper. Firstly, the output performance analysis and modeling of the TEG installed in the device under pressure are carried out. An enhanced heat transfer model of the system is proposed for the hydrothermal fluids in the flow channel of the device. Then, the thermoelectric model of TEG and the heat transfer model of the device are jointly simulated by using Fluent and Simulink software. Eventually, the simulation data are compared with the data obtained through experiments. The average absolute of the relative error of the open-circuit voltage is 5.07%, and the maximum one is 6.28%. The corresponding values of the maximum output power are 5.16% and 6.79%, respectively. Therefore, the performance of the hydrothermal thermoelectric power generation system and the correctness of the proposed overall co-simulation model are verified.

초대형 선박 폐열 열전발전시스템 내부 열전달 현상 규명

As environmental regulations on exhaust gas are being enforced around the world, and marine transportation is gradually being strengthened. It is believed that various methods will be attempted to the emission regulations. The thermoelectric power generation system can convert thermal energy into electrical energy. It can be applied without limiting the functions of the equipment and parts in the existing ship and has the advantage of not incurring large maintenance costs, which have spread to ship applications. In order to optimize the design of the thermoelectric power generation system, the heat transfer phenomenon due to the internal position was analyzed through CFD, and cross-validation was carried out through comparison with actual experimental values. Before conducting CFD of the thermoelectric power generation system, By setting the porous domain for the fin was applied to TEM to derive accurate results while reducing the calculation load. Comparing the fin that was applied to TEM and porous domain CFD results confirmed that the fin and porous domain CFD results have a great agreement with a maximum error of less than 0.5%. After that, performed a CFD of the entire thermoelectric power generation system, analyzed the heat transfer phenomena in a thermoelectric generator, and based on the results, conducted a comparison verification with the experimental results. The result of the comparison indicates the maximum error in the cooling jacket and power generation. This is analyzed in the experimental and CFD adiabatic efficiency difference, the heat loss difference at different locations in the actual experiment. In this study establishes an analysis methodology through comparative verification of experiments and CFD, It is expected that can optimize the design of thermoelectric power generation systems through the established methodology.

Thermoelectric Power Generation System for Vehicles with Weakly Mixing Engine Waste Heat

This research focuses on the development of a weakly mixing power system that utilizes engine waste heat in vehicles for thermoelectric generation of electricity. The system consists of a motor with integrated starting/electricity generation capabilities and a vehicle storage battery. Additionally, the system incorporates an engine exhaust waste heat temperature difference electricity generation device and a control system. The engine exhaust waste heat temperature difference electricity generation device is connected to the vehicle storage battery. By harnessing the engine exhaust waste heat, this power system enables the generation of electricity, which can be utilized to power the vehicle's starting mechanism and various electric equipment such as electric apparatus and air conditioners. The implementation of this system offers multiple benefits, including reduced fuel loss, energy conservation, and environmental protection.

Thermal management and waste heat recovery of electronics enabled by highly thermoconductive aramid composites with bridge-type 1D/2D liquid-crystalline thermal conduction networks

As a vital part of electronics, polymer-based thermal management materials effectively accelerate heat dissipation and improve the reliability, stability, and service life of electronics. Herein, a novel strategy of bridge-type 1D SiC nanowires/2D graphite flakes thermal conduction networks with liquid-crystalline orientation is developed to exploit highly thermoconductive aramid/graphite/SiC films (AGSs). The bridge-type 1D/2D liquid-crystalline thermal conduction networks can significantly promote efficient heat transport. The ultrahigh in-plane thermal conductivity of 19.69 ± 0.16 W m−1 K−1 can be achieved in AGSs, about 714 % higher than that of neat aramid. The thermal transport mechanism of composites at the atomic scale was explored based on phonon spectral analysis by molecular dynamics simulation. The developed AGSs can reduce the temperature of the operating phone CPU by about 3.4 °C when used as the heat dissipation material, and the AGSs also can conduct waste heat effectively to generate electric power in a thermoelectric power generation system. This work provides an effective strategy for thermal management and waste heat recovery of electronics by highly thermoconductive nanocomposites with bridge-type 1D/2D liquid-crystalline thermal conduction networks.

Performance enhancement for exhaust thermoelectric power generation system by using porous pin fins based on a fully automatic optimization method

An intelligent optimization method combining Non-dominated Sorting Genetic Algorithm-II (NSGA-II) algorithm and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) decision is implemented to design the optimal arrangement of porous pin fins in the flow channel of the exhaust thermoelectric power generation (ETEG) system. This method realizes the optimal arrangement of the porous pin fins while considering the two contradictory performance indicators at the optimization level: system output power (P) and pressure drop (Pd). In this work, the design of porous and solid pin fins is first compared. Secondly, four typical pin fins arrangement models are established with preliminary analysis. Finally, the NSGA-II-TOPSIS intelligent optimization method is implemented, which takes P and Pd as objective function, the position, number and relative distance of the porous pin fins as optimization variables simultaneously. Through iterative optimization, the optimal arrangement scheme achieves a proper balance between P and Pd. The main conclusions include: The design of the porous pin fins can increase 22.89% for P of the ETEG system while reduces 82.98% for Pd. The distribution of dense downstream of porous pin fins can best improve the ETEG system performance. After optimization, higher P and lower Pd of the ETEG system are obtained with fewer pin fins. A new index is proposed to evaluate optimal solutions, the optimal design with 2 porous pin fins reaches the highest value: 5.86 W Pa−1, which means that each pin fin is fully used.

Effect of thermoelectric modules with different characteristics on the performance of thermoelectric generators inserted in the central flow region with porous foam copper

The recovery and utilization of waste heat by thermoelectric power generation technology can effectively improve energy utilization efficiency and solve the problem of environmental pollution and resource shortage. In this study, a thermoelectric power generation system is established to recover and utilize high temperature waste heat for thermoelectric power generation. In order to improve the conversion efficiency of thermoelectric generator, porous foam copper is inserted into the central flow region of thermoelectric generator to enhance the heat transfer effect at the hot side, and the thermoelectric generator Comprehensive Performance (TEGCP) as a evaluation standard is used to analyze the performance of thermoelectric generator under the porous foam copper central flow region inserted method. The results show that the thermoelectric module with low thermal conductivity and high electrical conductivity can play a better performance in the thermoelectric generator. Moreover, the heat exchange capability of the thermoelectric generator heat exchanger can be significantly increased when the porous foam copper is inserted in the central flow region. Compared with an insert-free thermoelectric generator, the output power of the thermoelectric generator using porous foam copper with high pore density and high volume ratio is increased by 2.3 times. Through the TEGCP that, the use of 15 mm thickness (75 % volume ratio), 20PPI porous foam copper with the module KTGM161-18 and the central flow region inserted method has the best influence of the thermoelectric generator.

Improved immune genetic algorithm based TEG system reconfiguration under non-uniform temperature distribution

To deal with the problem of low thermoelectric conversion efficiency in thermoelectric power generation (TEG), this work designs an improved immune genetic algorithm (IIGA) to reconfigure TEG system under non-uniform temperature distribution (NTD) conditions to maximize power output. The traditional IGA is a fusion algorithm that combines genetic algorithm (GA) with immune algorithm (IA). Due to IGA's flaws of strict parameter setting and long computation time, three mountain factors are updated dynamically in IIGA to enhance the balance between local exploitation and global exploration. Consequently, the electrical connection of the TEG system is dynamically adjusted and reconfigured via IIGA, which can effectively improve power generation efficiency and reduce power consumption. The effectiveness and reliability of IIGA are testified and compared against four well-established meta-heuristic algorithms under two cases, i.e., 9 × 9 small TEG system and 15 × 15 large TEG system. Simulation results indicate that the output power boost by IIGA reaches 7.502 % under the 9 × 9 small TEG system and 10.281 % under the 15 × 15 large TEG system. Furthermore, a hardware-in-the-loop (HIL) experiment based on RTLAB platform is undertaken to testify the hardware implementation feasibility of IIGA affected by NTD conditions.

Experimental and Implementation of a 15 × 10 TEG Array of a Thermoelectric Power Generation System Using Two-Pass Flow of a Tap Water Pipeline Based on Renewable Energy

At the present time, the entire world is suffering from global climate change due to emissions caused by the combustion of fossil fuels. Thus, it is necessary to look for alternative power sources to generate clean electrical energy. Thermoelectric generators (TEG) are one of these alternatives. They convert thermal energy into useful electricity. There are many thermal energy sources such as hot water pipes. The current paper aims to convert waste heat from solar water-fed hot water pipes into electricity using a TEG panel made from 15 × 10 TEG modules. A pipe through which hot water flows serves as the hot side of the panel. The cold side of the panel is cooled using normal tap water. The maximum recorded temperature difference is 42.35 °C which yields an open-circuit voltage of 15.3 V. The maximum efficiency of the panel is 2.1% with an average energy production of 1.435 kWh. This proposed novel TEG panel system can be used continuously day and night. This is in contrast to a solar system, which operates only during the day, as it relies solely on solar radiation.

Optimal Reconfiguration of Thermoelectric Generation System Under Heterogeneous Temperature Difference

In view of the low efficiency of thermoelectric generation systems in different regions, this paper designs an optimization and reconfiguration of thermoelectric power generation system under heterogeneous temperature difference (HTD) based on particle swarm optimization (PSO) algorithm, so as to make full use of various thermal energy resources and obtain higher electrical output power, which realize multi-directional utilization of energy. In addition, PSO algorithm is a simple optimization strategy with a straightforward operation mechanism and fewer parameters to control during calculation. The research shows that when TEG array is in multiple HTD states, PSO algorithm has a stronger ability to get rid of local optimization, which can reduce power loss and improve energy conversion efficiency. On this basis, PSO algorithm is used to reconfigure the 15 × 15 symmetric TEG array. The experimental simulation analysis based on MATLAB platform is carried out to verify the feasibility of PSO algorithm.

Experimental study on heat energy recovery and utilization of coal gangue hill based on gravity heat pipe

The coal gangue hill is formed by the accumulation of waste in the coal mining process. A large amount of heat energy accumulates inside it, which makes it prone to spontaneous combustion, seriously pollutes the environment and wastes resources. In this paper, taking a gangue hill in a mining area as an example, a gravity heat pipe device is used to extract heat from the deep part of the gangue hill, and a mathematical model for heat extraction is established. And through experiments to explore the cooling effect of coal gangue at different depths, it is concluded that the cooling range of gravity heat pipe can reach about 15%. At the same time, to avoid the waste of geothermal resources, this paper uses the extracted heat twice and designs a thermoelectric power generation system based on the gravity heat pipe device to realize the purpose of resource utilization of the underground heat energy of coal gangue hills. The experimental results show that the thermoelectric conversion efficiency can reach 7.39%, and after the addition of the soaking plate, the thermoelectric efficiency is increased to 9.02%, which has a very important reference significance for promoting the treatment of coal gangue hills and the recovery and utilization of low-temperature geothermal heat.

Arithmetic optimization algorithm based MPPT technique for centralized TEG systems under different temperature gradients

Since centralized thermoelectric power generation (TEG) system presents multiple local maximum power points (LMPPs) at different temperature gradients (DTG), thus its optimal power harvesting is difficult to realize via conventional approaches. Therefore, an efficient arithmetic optimization algorithm (AOA) is applied to realize maximum power point tracking (MPPT) of centralized thermoelectric power generation system at different temperature gradients to improve the energy exploitation and utilization. AOA is utilized to efficiently and reliably identify unique global maximum power point (GMPP) in multiple LMPPs, which replicates the distribution mechanism of main arithmetic operators during mathematic calculation to find the best solution from a set of randomly generated candidate solutions. Compared with other well-known algorithms, AOA owns the distinctive superiorities of simple implementation structure, as well as few control parameters need to be tuning. Meanwhile, its own random and adaptive parameters selection principle greatly boost the AOA convergence performance. In addition, AOA shows strong ability to avoid falling into local optima thanks to its proper balancing between global exploration (diversification) and local exploitation (intensification). For further validation of the practicability of AOA based MPPT, two case studies are conducted, e.g., start-up test and step change of temperature. Experimental results show that AOA can achieve the optimal energy harvesting with minimal power fluctuations in comparison with the other three optimization algorithms, e.g., the energy produced by AOA is 34.44%, 6.03%, and 8.17% higher than that of perturb and observe (P&O), particle swarm optimization (PSO) and grey wolf optimization (GWO) respectively under the step change of temperature.

Research on Module Layout and Module Coverage of an Automobile Exhaust Thermoelectric Power Generation System

Due to the low efficiency of thermoelectric generators (TEGs), many scholars have focused on the structural optimization of TEGs rather than on the optimization of the layout of thermoelectric modules. We aimed to investigate the effect of module layout on the output power of an automotive exhaust thermoelectric power generation system. The module spacing and module coverage ratio were compared under different working conditions based on a numerical simulation. The results show that, under high-temperature conditions, when the module spacing expands from 5 mm to 35 mm, the output power growth rate of modules of different sizes ranges between 8% and 9%. Moreover, under low-temperature conditions, a high coverage ratio of modules will not increase the total output power but, instead, make it decline. In fact, choosing a larger-size module can improve the temperature uniformity, thereby increasing the output power of the automotive thermoelectric power generation system. Hence, the present study has verified that, under different working conditions, different module layouts and module coverage ratios have an impact on the output power of the thermoelectric power generation system, which sheds new light on the improvement of automotive thermoelectric power generation systems.

Experimental study on thermoelectric performance and power consumption characteristics of flat-plate thermoelectric generator

Thermoelectric generator can directly convert thermal energy into electrical energy, and applying it to recover waste heat from automobile exhaust is conducive to energy saving. In this paper, a thermoelectric generation experimental system is built, the power output performance and channel power consumption of the flat-plate thermoelectric power generation system under different exhaust gas flow rates are experimentally studied. The results show that when the exhaust flow rate is 40 Nm3/h and the exhaust inlet temperature is 400 °C, the maximum output power of the system is 26.8 W, and the maximum net output power is about 23.3 W. In addition, the exhaust flow rate is changed from 10 Nm3/h to 40 Nm3/h, and the proportion of power consumption in the hot air channel is changed from 1.91% to 12.85%, which has increased by more than six times.