A Structural Review of Thermoelectricity for Fuel Cell CCHP Applications

This article starts by introducing the ongoing South Africa electricity crisis followed by thermoelectricity, in which eighteen miscellaneous applicable case studies are structurally analysed in detail. The aim is to establish best practices for the R&D of an efficient thermoelectric (TE) and fuel cell (FC) CCHP system. The examined literature reviews covered studies that focused on the thermoelectricity principle, highlighting TE devices’ basic constructions, TEGs and TECs as well as investigations on the applications of thermoelectricity with FCs, whereby thermoelectricity was applied to recover waste heat from FCs to boost the power generation capability by ~7–10%. Furthermore, nonstationary TEGs whose generated power can be increased by pulsing the DC-DC power converter showed that an output power efficiency of 8.4% is achievable and that thicker TEGs with good area coverage can efficiently harvest waste heat energy in dynamic applications. TEG and TEC exhibit duality and the higher the TEG temperature difference, the more the generated power—which can be stabilised using the MPPT technique with a 1.1% tracking error. A comparison study of TEG and solar energy demonstrated that TEG generates more power compared to solar cells of the same size, though more expensively. TEG output power and efficiency in a thermal environment can be maximised simultaneously if its heat flux is stable but not the case if its temperature difference is stable. The review concluded with a TEC LT-PEM-FC hybrid CCHP system capable of generating 2.79 kW of electricity, 3.04 kW of heat, and 26.8 W of cooling with a total efficiency of ~77% and fuel saving of 43.25%. The presented research is the contribution brought forward, as it heuristically highlights miscellaneous thermoelectricity studies/parameters of interests in a single manuscript, which further established that practical applications of thermoelectricity are possible and can be innovatively applied together with FC for efficient CCHP applications.

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An Analysis Model Combining Gamma-Type Stirling Engine and Power Converter

Energies ◽

10.3390/en12071322 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1322 ◽

Cited By ~ 1

Author(s):

Hua-Ju Shih

Keyword(s):

Low Temperature ◽

Bias Voltage ◽

Temperature Difference ◽

Energy Harvester ◽

Waste Heat ◽

Power Converter ◽

Stirling Engine ◽

Living Environment ◽

Analysis Model ◽

Variable Capacitance

Waste heat is a potential source for powering our living environment. It can be harvested and transformed into electricity. Ohmic heat is a common type of waste heat. However, waste heat has the following limitations: wide distribution, insufficient temperature difference (ΔT < 70 K) for triggering turbines, and producing voltage below the open voltage of the battery. This paper proposes an energy harvester model that combines a gamma-type Stirling engine and variable capacitance. The energy harvester model is different from Tavakolpour-Saleh’s free-piston-type engine [7.1 W at ΔT = 407 K (273–680 K)]. The gamma-type Stirling engine is a low-temperature-difference engine. It can be triggered by a minimum ΔT value of 12 K (293–305 K). The triggering force in the variable capacitance is almost zero. Furthermore, the gamma-type Stirling engine is suitable for harvesting waste heat at room temperature. This study indicates that 21 mW of energy can be produced at ΔT = 30 K (293–323 K) for a bias voltage of 70 V and volume of 103.25 cc. Because of the given bias voltage, the energy harvester can break through the open voltage of the battery to achieve energy storage at a low temperature difference.

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The Experimental Research on Instantaneous Efficiency of PV/T Module Based on Micro Heat Pipe Array

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.732-733.306 ◽

2013 ◽

Vol 732-733 ◽

pp. 306-311

Author(s):

Zhen Hua Quan ◽

Lin Cheng Wang ◽

Yao Hua Zhao ◽

Yue Chao Deng ◽

Gang Wang ◽

...

Keyword(s):

Solar Cell ◽

Heat Pipe ◽

Thermal Efficiency ◽

Power Efficiency ◽

Waste Heat ◽

Energy Utilization ◽

Inlet Temperature ◽

Total Efficiency ◽

Micro Heat Pipe ◽

Key Factor

A novel photovoltaic /thermal (PV/T) module is invented, which use micro heat pipe array (MHPA), a flat heat pipe, to cool the solar cell. The PV/T module can achieve the purpose of cogeneration by collecting and utilizing waste heat while cooling the solar cell and improving power efficiency. In order to test the performance of PV/T module based on MHPA, instantaneous thermal efficiency test was performed. The intercept of measured instantaneous thermal efficiency curve can reach 41.4%, the slope is 3.95. The temperature of PV module is the key factor of the influencing electric efficiency. The PV/T modules electric efficiency is kept between 10.5% and 12.3% during the test. Solar energy utilization total efficiency at 20°C inlet temperature can reach more than 50%, and comprehensive performance efficiency can reach above 70%.

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The Experimental Study on Performance of Single Screw Expander with Air as Working Fluid

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1659 ◽

2013 ◽

Vol 634-638 ◽

pp. 1659-1664

Author(s):

Jing Fu Wang ◽

Yin Zhi Wang ◽

Yong Zhang ◽

Ying Wang

Keyword(s):

Temperature Difference ◽

Consumption Rate ◽

Waste Heat ◽

Thermal Power ◽

Maximum Temperature ◽

Working Fluid ◽

Total Efficiency ◽

Single Screw ◽

Experimental Apparatus ◽

Gas Consumption

A new single screw expansion machine was developed in order to improve the practical level of low temperature thermal power generation technology and the utilization of waste heat and renewable energy. With compressed air as working fluid, the power, efficiency, gas consumption rate and temperature difference of single screw expander with rotational speed variation had been studied in an established experimental apparatus of single screw expander . The results showed that, the maximum speed of expander reached 3393r/min, the maximum moment of torque reached 22N•m, the maximum power of expander was up to 4.4kW, and the maximum inlet flow rate was 32.9m3/h. The maximum temperature difference between import and export of expander reached 45°C. The lowest gas consumption rate was up to 55.2kg/kW•h, and the maximum total efficiency of expander reached 58.8%.

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Optimization of PEM Fuel Cell System Using Dynamic Model

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.26-28.1019 ◽

2010 ◽

Vol 26-28 ◽

pp. 1019-1026

Author(s):

Dong Ji Xuan ◽

Zhen Zhe Li ◽

Tai Hong Cheng ◽

Yun De Shen

Keyword(s):

Fuel Cell ◽

Dynamic Model ◽

Output Power ◽

Power Efficiency ◽

Cell System ◽

Optimal Operation ◽

Maximum Output ◽

Fuel Cell System ◽

Operation Condition ◽

Stack Model

The output power efficiency of the fuel cell system depends on the anode pressure, cathode pressure, temperature, demanded current, air and hydrogen humidity. Thus, it is necessary to determine the optimal operation condition for maximum power efficiency. In this paper, we developed a dynamic model of fuel cell system which contains mass flow model, membrane hydration and electro-chemistry model. Experiments have been performed to evaluate the dynamical Polymer Electrolyte Membrane Fuel Cell (PEMFC) stack model. In order to determine the maximum output power and minimum use of hydrogen in a certain condition, response surface methodology optimization based on the proposed PEMFC stack model is presented. The results provide an effective method to optimize the operation condition under varied situations.

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The Development of 50kW Output Power Atmospheric Pressure Turbine (APT)

Volume 3: Turbo Expo 2007 ◽

10.1115/gt2007-27783 ◽

2007 ◽

Cited By ~ 2

Author(s):

K. Tanaka ◽

K. Inoue ◽

J. Kitajima ◽

M. Kazari ◽

S. Nitta ◽

...

Keyword(s):

Power Generation ◽

Fuel Cell ◽

Output Power ◽

Atmospheric Pressure ◽

Gas Turbines ◽

Waste Heat ◽

Molten Carbonate ◽

General Process ◽

Distributed Power ◽

Distributed Power Generation

This research seeks to report the development of a 50kW output power atmospheric pressure turbine (APT), based on the Inverted Brayton Cycle, which puts new, distributed power generation technology to practical use by using as energy source gases at normal pressures and high temperature, from industrial furnaces, waste gasification furnaces, gas turbines, and fuel cells which work at high temperatures, (ex. MCFC: Molten Carbonate Fuel Cell, SOFC: Solid Oxide Fuel Cell) and attempts to save energy and reduce CO2. At the last conference (ASME Turbo Expo 2006 in Barcelona), we had presented a paper about the proposal of APT and the results of operation of a 3–5kw APT prototype. This paper describes the designing of a new 50kW output power APT, and shows performance analysis and a review of the effectiveness of its application to industrial furnaces and biomass gasification furnaces. This development is based on a 3–5 kW APT prototype we had built and operated, and evaluated results. The performance simulation results using a general process simulator “HYSYS” show that a new 50kW APT (with recuperating heat exchanger) has a net electric efficiency (LHV) of about 20%. Based on this simulation result, we calculated the power and economical performance of application to industrial furnaces and biomass boilers. The results of these calculations clarify the basic characteristics of a new APT, which can be used as a new system for distributed power generation using waste heat.

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A study of work and improve of water content in PEMFC with liquid cooling

Tyumen State University Herald Physical and Mathematical Modeling Oil Gas Energy ◽

10.21684/2411-7978-2020-6-2-8-21 ◽

2020 ◽

Vol 6 (2) ◽

pp. 8-21

Author(s):

Konstantin V. Agapov ◽

Dmitriy O. Dunikov ◽

Kirill D. Kuzmin ◽

Evgeniy V. Stoyanov

Keyword(s):

Fuel Cell ◽

Temperature Difference ◽

Test Bench ◽

Problem Area ◽

Solid Polymer ◽

Liquid Cooling ◽

Current Voltage ◽

Additional Resistance ◽

Overall Performance ◽

The Heat Balance

In this publication, in addition to focusing on the engineering component in creating our own test bench for trying various modes and the overall performance of solid polymer fuel cells with electric power of more than 2 kW, the features of the result of the operation of a liquid-cooled fuel cell in the field of heat transfer are displayed. It is known that its performance and service life depend on a properly tuned water and thermal balance of the fuel cell. The problem area is described in the insufficient moisture content of the supplied air to the fuel cell and the excess heat in the fuel cell. In this case, the negative consequence is that additional resistance to the rate of the electrochemical reaction is created, as a result of which the generated power decreases. A possible way to solve this problem is proposed: so, according to the heat balance equation, by increasing the temperature difference between the incoming and outgoing heat carrier, more heat energy can be removed. The temperature difference was achieved using a water-air radiator. The increased removal of thermal energy allowed the condensation of part of the moisture inside the fuel cell, maintaining the humidity and conductivity of the membrane, but not allowing flooding of the channels with liquid water, which otherwise could lead to a decrease in performance. During the tests, it was possible to increase the removed power by 321 w, which is 8.4% in excess of the maximum power. Based on the obtained experimental results, dependencies were constructed that are expressed by the current-voltage characteristic, power curve, the amount of heat removed by the water from the fuel cell, and a graph of the change in water temperature at the inlet and outlet of the fuel cell at various stages of operation.

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Multi-dimensional optimization of In0.53Ga0.47As thermophotovoltaic cell using real coded genetic algorithm

Scientific Reports ◽

10.1038/s41598-021-86175-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mansur Mohammed Ali Gamel ◽

Pin Jern Ker ◽

Hui Jing Lee ◽

Wan Emilin Suliza Wan Abdul Rashid ◽

M. A. Hannan ◽

...

Keyword(s):

Genetic Algorithm ◽

Output Power ◽

Waste Heat ◽

Antireflection Coating ◽

Base Layer ◽

Average Percentage ◽

Cell Efficiency ◽

Design Variables ◽

Real Coded Genetic Algorithm ◽

Dimensional Optimization

AbstractThe optimization of thermophotovoltaic (TPV) cell efficiency is essential since it leads to a significant increase in the output power. Typically, the optimization of In0.53Ga0.47As TPV cell has been limited to single variable such as the emitter thickness, while the effects of the variation in other design variables are assumed to be negligible. The reported efficiencies of In0.53Ga0.47As TPV cell mostly remain < 15%. Therefore, this work develops a multi-variable or multi-dimensional optimization of In0.53Ga0.47As TPV cell using the real coded genetic algorithm (RCGA) at various radiation temperatures. RCGA was developed using Visual Basic and it was hybridized with Silvaco TCAD for the electrical characteristics simulation. Under radiation temperatures from 800 to 2000 K, the optimized In0.53Ga0.47As TPV cell efficiency increases by an average percentage of 11.86% (from 8.5 to 20.35%) as compared to the non-optimized structure. It was found that the incorporation of a thicker base layer with the back-barrier layers enhances the separation of charge carriers and increases the collection of photo-generated carriers near the band-edge, producing an optimum output power of 0.55 W/cm2 (cell efficiency of 22.06%, without antireflection coating) at 1400 K radiation spectrum. The results of this work demonstrate the great potential to generate electricity sustainably from industrial waste heat and the multi-dimensional optimization methodology can be adopted to optimize semiconductor devices, such as solar cell, TPV cell and photodetectors.

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2D Nanomaterials for Effective Energy Scavenging

Nano-Micro Letters ◽

10.1007/s40820-021-00603-9 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Md Al Mahadi Hasan ◽

Yuanhao Wang ◽

Chris R. Bowen ◽

Ya Yang

Keyword(s):

Large Scale ◽

Waste Heat ◽

Material Selection ◽

Power Supplies ◽

Small Scale ◽

Energy Scavenging ◽

Power Sources ◽

Practical Applications ◽

2D Nanomaterials ◽

Self Powered

AbstractThe development of a nation is deeply related to its energy consumption. 2D nanomaterials have become a spotlight for energy harvesting applications from the small-scale of low-power electronics to a large-scale for industry-level applications, such as self-powered sensor devices, environmental monitoring, and large-scale power generation. Scientists from around the world are working to utilize their engrossing properties to overcome the challenges in material selection and fabrication technologies for compact energy scavenging devices to replace batteries and traditional power sources. In this review, the variety of techniques for scavenging energies from sustainable sources such as solar, air, waste heat, and surrounding mechanical forces are discussed that exploit the fascinating properties of 2D nanomaterials. In addition, practical applications of these fabricated power generating devices and their performance as an alternative to conventional power supplies are discussed with the future pertinence to solve the energy problems in various fields and applications.

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Modeling and Simulation of a Proton Exchange Membrane Fuel Cell Alongside a Waste Heat Recovery System Based on the Organic Rankine Cycle in MATLAB/SIMULINK Environment

Sustainability ◽

10.3390/su13031218 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1218

Author(s):

Sharjeel Ashraf Ansari ◽

Mustafa Khalid ◽

Khurram Kamal ◽

Tahir Abdul Hussain Ratlamwala ◽

Ghulam Hussain ◽

...

Keyword(s):

Fuel Cell ◽

Waste Heat Recovery ◽

Proton Exchange Membrane ◽

Waste Heat ◽

Organic Rankine Cycle ◽

Rankine Cycle ◽

Proton Exchange ◽

Waste Heat Recovery System ◽

Recovery System ◽

Exchange Membrane

The proton exchange membrane fuel cell (PEMFC) is the fastest growing fuel cell technology on the market. Due to their sustainable nature, PEMFCs are widely adopted as a renewable energy resource. Fabricating a PEMFC is a costly process; hence, mathematical modeling and simulations are necessary in order to fully optimize its performance. Alongside this, the feasibility of a waste heat recovery system based on the organic Rankine cycle is also studied and power generation for different operating conditions is presented. The fuel cell produces a power output of 1198 W at a current of 24A. It has 50% efficiency and hence produces an equal amount of waste heat. That waste heat is used to drive an organic Rankine cycle (ORC), which in turn produces an additional 428 W of power at 35% efficiency. The total extracted power hence stands at 1626 W. MATLAB/Simulink R2016a is used for modeling both the fuel cell and the organic Rankine cycle.

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