Abstract
In this study, two systems are brought forward to recover the waste heat of a proton exchange membrane fuel cell (PEMFC), which are named the organic Rankine cycle (ORC), and heat pump (HP) combined organic Rankine cycle (HPORC). The performances of both systems are simulated on the platform of MATLAB with R123, R245fa, R134a, water, and ethanol being selected as the working fluid, respectively. The results show that, for PEMFC where operating temperature is constantly kept at 60 °C, there exists an optimum working temperature for each fluid in ORC and HPORC. In ORC, the maximal net power can be achieved with R245fa being selected as the working fluid. The corresponding thermal efficiency of the recovery system is 4.03%. In HPORC, the maximal net power can be achieved with water being selected in HP and R123 in ORC. The thermal efficiency of the recovery system increases to 4.73%. Moreover, the possibility of using ORC as the cooling system of PEMFC is also studied. The heat released from PEMFC stack is assumed to be wholly recovered by the ORC or HPORC system. The results indicate that the HPORC system is much more feasible for the cooling system of a PEMFC stack, since the heat recovery ability can be promoted due to the presence of HP.
Highlights
In the 21st century, with the increasing worldwide concern regarding fossil-fuel depletion and environment protection, alternative renewable clean energy is in urgent demand
We consider the performance of proton exchange membrane fuel cell (PEMFC) with organic Rankine cycle (ORC) or HPORC acting as the cooling system
HPORC; Pele is the electric power of PEMFC
Summary
In the 21st century, with the increasing worldwide concern regarding fossil-fuel depletion and environment protection, alternative renewable clean energy is in urgent demand. Zakaria et al [2] modeled the energy recovery system of a fuel cell vehicle (FCV), which utilizes the waste heat of the fuel cell stack to increase the inlet hydrogen temperature to improve the conversion efficiency through higher kinetic reaction rates. The temperature difference between the evaporator and the condenser in ORC system needs to be large enough to guarantee a high Rankine efficiency. The condenser in ORC system needs to be large enough to guarantee a high Rankine efficiency This may lead to a small temperature difference between the working fluid and the heat. It provides the possibility to control the heat resource temperature for the ORC little work. It provides the possibility to control the heat resource temperature for the ORC system system by changing the temperature ratio of the heat pump.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
