Thermoelectric Cooler Research Articles

Estimating the Impact of a Recuperative Approach on the Efficiency of Thermoelectric Cooling

Thermoelectric cooling is a prospective technology that has a lot of advantages; however, its main drawback is its low efficiency compared to other technologies. A lot of scientific research is aimed at the improvement of the efficiency of thermoelectric cooling, including the development of new thermoelectric materials, innovative structures, and better power management strategies. The present work further explores a self-developed recuperative power management approach, which takes advantage of the thermoelectric element’s ability to work as an electrical generator. This study relied on the thermal–electrical analogy method to develop a model that is capable of describing the impact of recuperation on the cooling performance while preserving the simplest configuration possible. The influence of different variables was estimated by three suggested quantities for evaluating the gains, losses, and rationality of the recuperative approach. A recovery of up to 10% of the electrical energy supplied to the thermoelectric element was observed experimentally. The ratio between the recovered energy and induced heat losses did not exceed a factor of 0.9. It is concluded that the recuperation process is reasonable only in the case of unavoidable interruption of the cooling process when average-performance thermoelectric elements are used.

Organic flexible thermoelectrics for thermal control

Despite the lower efficiency for thermoelectric cooling technology compared to conventional mechanical cooling technology, it finds application in commercial portable cooling due to its compactness, simple device design, and low noise. The rapid progress in flexible and wearable electronics opens the need for flexible cooling technology for local thermal regulation where thermoelectric cooling technology offers niche advantages suitable for flexible cooling such as light weight and no moving parts. Organic thermoelectrics hold promise for flexible and wearable cooling applications due to their intrinsic mechanical flexibility, low thermal conductivity, and ease of processing. However, research on organic Peltier cooling devices remains limited, and more work is required to exploit their potential for flexible cooling applications. This review discussed the state-of-the-art organic Peltier cooling devices and the materials and device design considerations required for advancing organic Peltier device technology toward practical applications.

Renewable energy integration for sustainable cold storage: Designing a solar PV operated thermoelectric cool chamber

Thermoelectric coolers utilizing peltier effect offer a promising solution for cooling applications. This study elaborates the design and optimization of a TEC-operated cool chamber and evaluation of developed thermoelectric cool chamber. A number of elements need to be carefully considered during the design process, including heat load assessment, TEC module selection and effective heat dissipation techniques. Appropriate TEC modules are chosen based on estimated cooling load, temperature difference achieved, power consumption, maximum cooling capacity of each TEC and heatsink. The solar photovoltaic operated thermoelectric cool chamber comprises essential components such as SPV Panel, solar charger controller, battery, PWM controller, TEC module with heat sink, and insulated box (TCC unit). The design considerations involve estimating total power consumption and determining the number and ratings of solar panels, batteries, and power conditioning devices to ensure reliable electricity supply. The system operates on SPV-generated power, utilizing MPPT charge controllers to maximize power output. Pulsed width modulation (PWM) systems efficiently regulate power distribution to thermoelectric modules, optimizing performance. The thermoelectric cool chamber was developed of 40 L water capacity. It was observed that, the chamber and water temperature in developed thermoelectric cool chamber was reduced from initial temperature by 11.85°C and 11.56°C, respectively after 24 hours. The chamber and water temperature after 24 hours were 13.31°C and 13.49°C, respectively. The performance evaluation showed that the chamber’s cooling efficiency was influenced by factors such as cooling load and water volume. This comprehensive approach enables the development of an effective and sustainable thermoelectric cooling system suitable for various applications.

Comparative Analysis of Peltier Devices and Flexible Heater Strips for Enhancing Bandwidth in Thermo-Active Soft Actuators

Soft actuators are a new generation of robotic actuators designed for safer and more adaptable physical human-robot interaction, that can be triggered by various stimulating mechanisms, including pneumatic, electric, electromagnetic, light, magnetic, and thermal sources. Among the different types of soft actuators, thermoresponsive ones that utilize heat as the stimulus show great potential due to their ability to deliver a relatively high force-to-size ratio without the need for external air pumps, tethers, high voltage sources, or complex designs. However, a major drawback of such actuators is their limited bandwidth. Traditional methods rely on Joule heating for actuation, with the actuator deflating when the heat source is turned off and ambient temperature takes over. Recently, the Peltier mechanism has been introduced as an alternative approach for active heating and cooling. This research paper presents a comparative analysis of the Peltier and flexible heater mechanisms in terms of the bandwidth and energy consumption of phase-change thermo-active soft actuators. The study aims to assess the potential of Peltier-based actuation in addressing the bandwidth limitations observed in traditional soft actuators. The findings reveal that Peltier-based actuation can significantly improve actuation speed in thermoresponsive soft actuators. However, it is important to note that the performance of Peltier-based actuators decreases after a few cycles unless additional measures, such as the use of an external fan, are implemented. This increase in performance comes at the cost of higher energy consumption, which should be carefully considered in practical applications.

Cloud chamber using Peltier cooling

The design of a simple, compact, inexpensive cloud chamber is described and examples of particle tracks from cosmic rays and a radioactive sample are shown. A temperature gradient is established in the chamber through the use of a simple heater at the top and Peltier modules at the base, eliminating the need for dry ice. Using a few millilitres of isopropyl alcohol it starts to show particle tracks a few minutes after being switched on and operates for over two hours without any intervention. The cloud chamber is constructed using components that can be readily obtained at a total cost of about £40.

Investigation on a novel hybrid system based on radiative sky cooling and split thermoelectric cooler driven by photovoltaic cell

This paper develops a novel cooling and heating system by integrating a novel split thermoelectric cooler (STEC) with photovoltaic power generation and radiative sky cooling. The system uses photovoltaic driven STEC modules to generate cooling and heating combined with radiative sky cooling to improve cooling capacity. By harnessing the distinctive characteristics of photovoltaic technology and radiative sky cooling, the new system is capable of operating continuously for 24 h without requiring any additional energy input. The system mathematical model is established, and the effects of STEC module number, solar illumination intensity, area ratio and ambient temperature on the performance are studied. Results demonstrate that the cooling efficiency of the system is 3.02 and the heating efficiency is 1.86 when the number of STEC modules is 3. In a year, the monthly average heat production of the system fluctuates due to changes in the solar illumination intensity, while the fluctuation of cooling capacity is small. The system cold production is larger than heat production, which is more suitable for application in the area with high demand for year-round refrigeration. The new system has good energy and economic performance with payback time being shorter than that of the photovoltaic-air conditioning system.

Performance analysis of four-stage thermoelectric cooler for focal plane infrared detectors

A cooler provides a low-temperature working environment for refrigerated infrared detection chips and is an indispensable component in infrared detectors that ensures their smooth operation. In this paper, a thermodynamic model of a heat-pipe-type four-stage thermoelectric cooler with a large temperature difference applied to a focal plane infrared detector is constructed. The heat leakage of the detector is calculated using the model. The performance indexes of the coordination performance coefficient and module utilization coefficient are used to unify the cooling capacity and economic performance of the device. The impression of the working current, heat pipe parameters, and cross-sectional area of the thermoelectric leg on the performance of cooler are analyzed. A Pareto optimal solution is obtained using an NSGA-II algorithm and TOPSIS decision. A low cooling temperature is obtained using a multistage thermoelectric cooler to achieve a large cooling temperature difference. When the working current is 5.65 A and the cross-sectional area is 4.5 mm2, the maximum cooling temperature difference reaches 110.6 °C, and the lowest cooling temperature reaches -83.6 °C. When the working temperature of the detector is -60 °C, the current and cross-sectional area corresponding to the optimal solution of cooling capacity-COP-power consumption are 1.51 A and 2.74 mm2, respectively.

Realizing rapid cooling and latent heat recovery in the thermoelectric-based battery thermal management system at high temperatures

To realize rapid cooling of the battery at high temperatures and effective latent heat recovery from phase change materials (PCMs), a thermoelectric-based battery thermal management system (BTMS) is proposed. Additionally, a transient multiphysics numerical model is developed to predict the system's thermal performance, and the concept of the latent heat recovery rate of PCMs is introduced. Results show that the introduction of thermoelectric coolers (TECs) significantly enhances the system's efficiency in cooling the battery at high temperatures (Stage 1) and recovering PCM latent heat (Stage 2). The overall thermal performance can be further improved by utilizing PCMs with a higher mass fraction of expanded graphite (EG) or increasing the TEC input current. Moreover, after the end of Stage 2, the power supply for TECs is interrupted, and the system enters Stage 3, which only relies on PCMs to control the battery temperature. The duration of Stage 3 increases with the EG mass fraction, achieving a peak of 3830 s at an EG mass fraction of 12%. Considering the thermal performance and power consumption of the system, the optimal solution is determined as an EG mass fraction of 12% and a TEC input current of 4 A. In this situation, the required time for Stage 1 and Stage 2 is 170 s and 620 s, with the latent heat recovery rate of PCMs up to 361.94 J/kg/s. The findings will provide new insights for the development of the thermoelectric-based BTMS.

Effect of the thermal processing on the microstructural, functional and mechanical properties of cast polycrystalline NiMnTi alloys

The solid-state refrigeration and heat pumping field is gaining increasing attention as an alternative solution to the conventional vapour-based cooling devices. Among the shape memory alloys (SMAs), besides the reference NiTi system, outstanding elastocaloric performances are exhibited by the NiMnTi alloy. In this work, we produced two cast NiMnTi alloys which were characterized in terms of microstructural, structural, functional, and mechanical properties. Moreover, we assessed the effect of the heat treatments on the microstructure and on the physical properties of the produced alloys by calorimetric, structural and high-temperature microscope analyses. Furthermore, the heat treatments promoted partial mechanical cycling stability and a superelastic behavior without significant residual strains. Finally, the elastocaloric performance of the alloy was evaluated by direct adiabatic ΔT measurements upon elastocaloric cycles in four different loading conditions. The alloys exhibited promising elastocaloric performance for possible solid-state cooling applications. In particular, the best adiabatic ΔT value achieved in this work was 8.7 °C with a strain rate of 400 %/min and up to a strain of 5 % for the NiMnTi heat treated at 900°C.

Long-Lasting Heat Dissipation of Flexible Heat Sinks for Wearable Thermoelectric Devices.

Flexible wearable thermoelectric (TE) devices hold great promise for a wide range of applications in human thermal management and self-powered systems. Currently, the main challenge faced by flexible TE devices is the inadequate dissipation of heat, which hinders the maintenance of significant temperature differences over prolonged periods. Most existing heat sinks, being rigid in nature, compromise the overall flexibility of the device. Therefore, the challenge lies in maintaining device flexibility while ensuring effective heat dissipation. In this study, we developed a flexible phase-change material (FPCM) heat sink to address this issue and enhance the heat dissipation capabilities of TE devices (FPCM-TED). When used as a thermoelectric cooler (TEC), the FPCM heat sink efficiently absorbs heat from the hot end, enabling long-lasting and high-performance cooling of the TEC. This capability effectively reduces body temperature by up to 11.21 °C and can be sustained for at least 300 s. Additionally, when employed as a thermoelectric generator (TEG), the FPCM absorbs heat at the cold end, thereby increasing the temperature difference between the hot and cold ends and enhancing the output performance of the device. By integrating FPCM-TED into a fabric wristband, we successfully developed a self-powered wireless pedometer sensing system. This breakthrough lays a solid foundation for the application of wearable, smart clothing.

Solar Powered Thermoelectric Air Conditioning for Temperature Control in Poultry Incubators

Proper air conditioning is crucial for hatching, growing, and reproducing poultry chickens. The existing methods are often costly and only viable for some chicken farmers. This paper presents a novel solar-powered thermoelectric module that utilizes the Peltier effect for efficient cooling and heating in poultry incubators. The proposed system consists of a Peltier module with cool and hot junctions, powered by a solar panel through a charge controller and battery. The cool junction is located in the chicken-breeding and reproduction unit, while the hot junction is situated in the egg-incubation unit. Temperature controllers maintain the required temperatures of 35–40 °C for the egg-hatching and 10–24 °C for the chicken-growing units. The experimental results demonstrate the system’s effectiveness in maintaining the desired temperatures. This solar-powered thermoelectric air conditioning system offers advantages over traditional methods, including lower energy consumption, reduced costs, and eco-friendliness. It has the potential to benefit off-grid poultry farmers and reduce energy bills for existing chicken farms. The mathematical modeling, load calculations, and prototype results show that the proposed system is best suited for providing the required cooling and heating effects in poultry incubators. This research represents a significant step forward in temperature control for poultry incubators and could revolutionize poultry farming practices, especially in remote locations with limited electricity access.

Modeling of a hybrid stirling engine/desalination system using an advanced machine learning approach

In this study, the performance of a hybrid power/freshwater generation system is modeled using a coupled artificial neural network (ANN) model with a pelican algorithm (PA). The proposed system is composed of a Stirling engine fixed to a solar dish, a desalination unit, and a thermoelectric cooler. The Stirling engine is used to generate the electricity required to operate the electrical-powered components of the system as well as to preheat the saline water. The thermoelectric cooler is used to supply the saline water with additional heat as well as to cool the condensation surface of the desalination unit. The performance of the proposed system in terms of water yield, generated power, and system efficiency was considered as the model's output; while the solar irradiance and dish diameter were considered as the model's inputs. In addition to the pelican algorithm, a conventional gradient descent optimizer was employed as an internal optimizer of the ANN model. The prediction accuracy of the two models was compared based on different accuracy measures. The ANN-PA outperformed the conventional ANN model in predicting the water yield, generated power, and system efficiency. The computed root mean square errors of the ANN and ANN-PA models were (1.982 L, 104.863 W, and 1.227 %) and (0.019 L, 1.673 W, and 0.047 %) for water yield, generated power, and system efficiency, respectively.

Wide working temperature range and large electrocaloric effect in BaTiO3 based ceramics achieved by regulating phase boundaries through a compensatory ion co-doping strategy

Electrocaloric refrigeration shows the merits of environmental safeguarding, large efficiency, easy combination, and miniaturization as a novel solid-state refrigeration technique. In this paper, Sn4+ is doped into the B site of BLNT ceramics. By adjusting the doping content, the T-C phase transition peak was successfully shifted to room temperature and promoted the formation of relaxor ferroelectrics, resulting in a wider operating temperature range (Tspan) and improved adiabatic temperature change (ΔT). A comprehensive study was conducted on the crystal structure, surface morphology, dielectric properties, ferroelectricity, and electrical properties of BLNTS ceramics with varying levels of Sn4+ doping. Wherein, when the doping amount is 5Sn, a maximum adiabatic temperature change value (ΔTmax) of 1.14 K was obtained, and the temperature span (Tspan) reached 45 °C (Tspan is defined as ΔT ≥ 80 % ΔTmax). This work proposes a high-performance environmentally friendly electrocaloric effect (ECE) material suitable for solid-state cooling applications.

Significantly enhanced electrocaloric effect by composition modulation in lead-free BaTiO3-based ceramics

The electrocaloric effect (ECE) offers a pathway to environmentally sustainable and easily miniaturized refrigeration technology, positioning it as a front-runner for the next generation of solid-state cooling solutions. This research unveils a remarkable ECE in a finely tuned (Ba0.86Ca0.14)0.98La0.02Ti0.92Sn0.08O3 ceramic, exhibiting a temperature shift (ΔT) of 1.6 K across more than 85% of the maximum ΔT (ΔTmax) and spanning an exceptionally wide operational range of 92 K. Our investigation on dielectric responses and ferroelectric polarization-electric field (P–E) loops suggests that the broad operational scope results from the fragmentation of extended ferroelectric domains into smaller domains and polar nano-regions (PNRs) supported by PFM analysis. Furthermore, the introduction of La enhances spontaneous polarization by significantly extending the maximum electric field that can be applied, facilitating high-performance ECE at ambient temperature. This study positions BaTiO3-based lead-free ceramic as a sustainable alternative for addressing the cooling demands of modern electronic components, marking a significant stride toward next-generation solid-state refrigeration.

Photovoltaic Powered Dual Thermoelectric Air Conditioning System

Abstract: Nowadays energy efficient and environment friendly systems are among the emerging technologies, due to growing concerns about climate change and sustainability. According to the present scenario, the renewable energy resources are becoming the source of energy due to the decrease in non-renewable energy resources (Fossil fuels). So we presented a “Photovoltaic-Powered Dual Thermoelectric Air Conditioning System” that incorporates Peltier modules(thermoelectric material) which works on peltier effect known for their eco-friendly characteristics. Harnessing solar energy through a highefficiency PV array, this system aims to provide efficient and sustainable air conditioning while minimizing the reliance on traditional power sources. The additional benefit of this system is that it provides year round comfort i.e. cooling and heating facility in one system.

Development of a Solar-Powered Barley Sprouting Room

The study aims to develop a sprouting room for barley powered by solar energy instead of traditional alternating-current rooms to suit remote areas. The cooling, lighting, and irrigation systems were developed and replaced with another that operates on 12 V DC. An air cooling device based on the Peltier module has been developed as an alternative to air conditioning devices. Four cooling units of the air cooler were tested with three lighting durations of 6, 9, and 12 h and three irrigation rates of 1.7, 1.85, and 2 m3 ton-1. The measurements included evaluating the performance of the developed air cooler device. The vegetative and quality characteristics and a chemical analysis of sprouted barley for the solar-powered room compared to the room before the modification were estimated. The solar room's productivity and electrical energy consumption rates were estimated, and an economic evaluation of the development was conducted. The maximum electrical power consumption for the solar-powered sprouting room was 63.275 kWh ton-1, compared with 117.19 kWh ton-1 for the alternating current-managed room before modification. The interaction between the utilized developing DC air cooling, lighting, and irrigation achieved standard rates for the produced barley vegetative and quality characteristics. The maximal productivity from sprouted barley was 1.22 tons, per 7 days with an increment ratio over control of 31.97%. The net earnings for the developed sprouting room were maximized relative to the significant decrease in electrical production costs. The developed room fits the livestock sector by providing good economic alternative fodder sources.

Effect of heat treatment on phase transformation behavior and properties of Ni-Co-Mn-Al-Y shape memory alloy by laser direct energy deposition

Laser direct energy deposition (LDED) of Ni-Co-Mn-Al-Y magnetic shape memory alloys (MSMAs) with high elastocaloric properties has important application prospects in solid-state refrigeration. However, because the microstructure of laser non-equilibrium metallurgy does not have reversible martensitic transformation, further regulating the microstructure of deposited samples through scientific post-heat treatment to obtain better properties is still a top priority. In this work, Ni-Co-Mn-Al-Y alloy samples were prepared by an optimized LDED process, and then the deposited samples were heat-treated with different temperatures. The results showed that the sample subjected to heat treatment with 550 °C × 3.5 h + 1100 °C × 20 h had maximum entropy change of the phase transformation, compressive properties, and elastocaloric effect. The compressive fracture strength was up to 1327 MPa, the maximum compressive strain was up to 26.2%, and an adiabatic temperature change was up to −4.3 K under the condition of rapid unloading. Characterization of the microstructure changes of the alloy under 11 cycles of compression revealed that the deformation mechanism was mainly planar sliding of dislocations in the martensite and dislocation cutting the γ(Y-rich) phase. The alloy prepared by the optimizing LDED and heat treatment process had better cycle stability and preliminary refrigeration capacity.

Evaluation of Efficiency Enhancement in Photovoltaic Panels via Integrated Thermoelectric Cooling and Power Generation

Among renewable resources, solar energy is abundant and cost effective. However, the efficiency and performance of photovoltaic panels (PVs) are adversely affected by the rise in the surface temperature of solar cells. This paper analyzes the idea of utilizing thermoelectric modules (TEMs) to enhance the efficiency and performance of PV panels. The proposed hybrid solar thermoelectric generation (HSTEG) system employs TEMs as thermoelectric coolers (TECs) to enhance panel efficiency and as thermoelectric generators (TEGs) to convert excess heat into additional electricity. This study includes an extensive evaluation of the proposed idea using MATLAB Simulink and experimental validation in indoor as well as outdoor environments. The use of TECs for the active cooling of the PV system leads to an increase in its efficiency by 9.54%. Similarly, the passive cooling by TECs along with the additional power generated by the TEGs from the excessive heat led to an increase in the efficiency of the PV system of 15.50%. The results demonstrate the HSTEG system’s potential to significantly improve PV panel efficiency and energy generation, offering a promising avenue for advancing solar energy technology.

Multi-Stage Thermoelectric Coolers Current Optimization for Infrared Detectors Based on the SNOPT-Finite Element Method

At present, series power supply has been widely used in multi-stage thermoelectric coolers (TEC), however, the series power supply cannot fully utilize the full cooling capability of multi-stage TEC. In this paper, according to the actual working conditions of IR detector coolers, three multi-stage TEC models with different numbers of stages were established, and a new method of SNOPT-FEM coupled analysis was adopted to individually optimize the current of each stage. The method considers the synergistic influence of inter-stage thermoelectric effects, which makes the simulation results closer to reality and improves the model solution efficiency with the help of algorithms, which shortens the computation time by at least 46%. The results show that the cold side temperatures of 3-stage, 4-stage, and 5-stage thermoelectric coolers with separated and separated algorithmic power supply can be reduced by 7.95 K and 8.59 K, 8.20 K and 9.04 K and 8.37 K and 9.13 K, respectively, compared with the series power supply. The large cooling temperature difference under separated and separated algorithmic power supplies was achieved at the expense of more power consumption and lower COP compared with the series power supply. Therefore, high-power sources are required to meet the cooling needs of IR detectors in engineering applications. It is thus evident that the proposed method is favorable to promote the application of thermoelectric cooling in infrared detection.

Performance analysis of a refrigeration system integrated with a thermoelectric cooler and microchannels in terms of heat transfer using a hybrid nanofluid

Advancements in chip technology increase energy consumption due to larger chip capacity, leading to intensive heat flux generation. Cooling solutions, including fan-only, fan-conventional heat sink (HS), or fan-conventional HS-heat pipe (HP) integrated systems, face penalties such as noise, dust accumulation, high electricity usage, space constraints, and thermal limitations of the working fluid. While thermoelectric coolers (TEC) have advantages like compactness and noise-free operation, they alone are insufficient for cooling sophisticated chips; combining them with microchannel heat sinks (MCHS) and superior fluid is crucial for achieving faster and more efficient cooling. Considering previous studies involving TECs used alone, with conventional fluids integrated into MCHS, and with a mono-nanofluid integrated into MCHSs, this is the first study to consider a TEC integrated with two MCHSs and to use a ZnO-TiO2/water hybrid nanofluid to maximize the performance of this miniature refrigeration system. Accordingly, an experimental study was carried out on the aforementioned refrigeration system using various concentrations (φ) of ZnO-TiO2/water hybrid nanofluid for different flow rates, utilizing both conventional heat transfer and the TEC’s mathematical operating principle. The results were interpreted via Reynolds number, Prandtl number, heat transfer rate, Nusselt number, total thermal resistance, and coefficient of performance (COP). The increase in φ from 0% to 0.03%, accompanied by a decrease in flow rate from 16 × 10−5 m3/s to 9 × 10−5 m3/s, increased the heat transfer rate for the heat-absorbing and the heat-emitting sides of the refrigeration system from 19.510 W to 45.794 W, and 13.639 W to 22.406 W, respectively. The experimental COP for pure water was 0.325 at the lowest volume flow rate, but increased to 0.934 at a φ of 0.030%. Considering the thermal characteristics, this study demonstrates that the proposed system is particularly advantageous at low flow rates and high φ, making it a potential candidate for electronic circuit cooling. Considerations such as investigating certain material properties to allow for further improvement of the proposed system were offered.