Passive Fuel Cell Heat Recovery Using Heat Pipes to Enhance Metal Hydride Canisters Hydrogen Discharge Rate: An Experimental Simulation

Waste heat recovery systems are used to recover the waste heat in all possible ways. It saves the energy and reduces the man power and materials. Heat pipes have the ability to improve the effectiveness of waste heat recovery system. The present investigation focuses to recover the heat from Heating, Ventilation, and Air Condition system (HVAC) with two different working fluids refrigerant(R410a) and nano refrigerant (R410a+Al2O3). Design of experiment was employed, to fix the number of trials. Fresh air temperature, flow rate of air, filling ratio and volume of nano particles are considered as factors. The effectiveness is considered as response. The results were analyzed using Response Surface Methodology

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Hybrid direct carbon fuel cell-thermoradiative systems for high-efficiency waste-heat recovery

Energy Conversion and Management ◽

10.1016/j.enconman.2019.111842 ◽

2019 ◽

Vol 198 ◽

pp. 111842

Author(s):

Xin Zhang ◽

Jianying Du ◽

Yee Sin Ang ◽

Jincan Chen ◽

Lay Kee Ang

Keyword(s):

Fuel Cell ◽

Heat Recovery ◽

Waste Heat Recovery ◽

High Efficiency ◽

Waste Heat ◽

Direct Carbon Fuel Cell

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Energetic Based Organic Fluid Selection for a Solid Oxide Fuel Cell-Organic Rankine Cycle Combined System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.1162 ◽

2012 ◽

Vol 622-623 ◽

pp. 1162-1167

Author(s):

Han Fei Tuo

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Heat Recovery ◽

Waste Heat ◽

Solid Oxide ◽

Exhaust Gas ◽

Oxide Fuel ◽

Gas Temperature ◽

Selection For ◽

Exhaust Gas Temperature

In this study, energetic based fluid selection for a solid oxide fuel cell-organic rankine combined power system is investigated. 9 dry organic fluids with varied critical temperatures are chosen and their corresponding ORC cycle performances are evaluated at different turbine inlet temperatures and exhaust gas temperature (waste heat source) from the upper cycle. It is found that actual ORC cycle efficiency for each fluid strongly depends on the waste heat recovery performance of the heat recovery vapor generator. Exhaust gas temperature determines the optimal fluid which yields the highest efficiency.

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Studying a Hybrid System Based on Solid Oxide Fuel Cell Combined With an Air Source Heat Pump and With a Novel Heat Recovery

Journal of Electrochemical Energy Conversion and Storage ◽

10.1115/1.4041864 ◽

2018 ◽

Vol 16 (2) ◽

Author(s):

Giulio Vialetto ◽

Marco Noro ◽

Masoud Rokni

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Electric Power ◽

Heat Pump ◽

Heat Recovery ◽

Research Work ◽

Solid Oxide ◽

Coefficient Of Performance ◽

Oxide Fuel ◽

Air Source Heat Pump

In this paper, a new heat recovery for a microcogeneration system based on solid oxide fuel cell and air source heat pump (HP) is presented with the main goal of improving efficiency on energy conversion for a residential building. The novelty of the research work is that exhaust gases after the fuel cell are first used to heat water for heating/domestic water and then mixed with the external air to feed the evaporator of the HP with the aim of increasing energy efficiency of the latter. This system configuration decreases the possibility of freezing of the evaporator as well, which is one of the drawbacks for air source HP in Nordic climates. A parametric analysis of the system is developed by performing simulations varying the external air temperature, air humidity, and fuel cell nominal power. Coefficient of performance (COP) can increase more than 100% when fuel cell electric power is close to its nominal (50 kW), and/or inlet air has a high relative humidity (RH) (close to 100%). Instead, the effect of mixing the exhausted gases with air may be negative (up to −25%) when fuel cell electric power is 20 kW and inlet air has 25% RH. Thermodynamic analysis is carried out to prove energy advantage of such a solution with respect to a traditional one, resulting to be between 39% and 44% in terms of primary energy. The results show that the performance of the air source HP increases considerably during cold season for climates with high RH and for users with high electric power demand.

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Waste Heat Recovery for Powering Mobile Devices Using Thermoelectric Generators and Evaporatively-Cooled Heat Sink

ASME 2018 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems ◽

10.1115/ipack2018-8354 ◽

2018 ◽

Author(s):

Michael Ozeh ◽

A. G. Agwu Nnanna

Keyword(s):

Heat Pipe ◽

Mobile Devices ◽

Heat Recovery ◽

Waste Heat Recovery ◽

Waste Heat ◽

Heat Pipes ◽

Loop Heat Pipe ◽

Thermoelectric Voltage ◽

Voltage Generation ◽

Alternate Source

Powering small electronics like mobile devices off-grid has remained a challenge; hence, there exists a need for an alternate source of powering these devices. This paper examines the efficacy of a novel nanoparticle-immobilized polyethylene wick in maintaining sufficient thermal gradient across a thermoelectric generator to power these devices with energy from waste heat. The work examines several other heat exchangers including heat pipes and loop heat pipe setups. The experimental evidence reveals that the nanoparticle-immobilized polyethylene wick is capable of generating sufficient thermal potential resulting in 5V, which is the minimum voltage required to power small mobile devices. In the opinion of the authors, this is the first ever recorded account of utilizing waste heat to generate enough voltage to power a mobile device. Experiment demonstrated that the nanoparticle-immobilized polyethylene wick showed over 40% thermoelectric voltage generation increment over a plain polyethylene wick and a metal wick in a loop heat pipe setup.

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