Investigation of off-design characteristics of solid oxide electrolyser (SOE) operated in endothermic conditions

¹ Department of High Temperature Electrochemical Processes (HiTEP), Institute of Power Engineering, Augustowka 36, 02-981 Warsaw, Poland
² Institute of Heat Engineering, Warsaw University of Technology, Nowowiejska 21/25, 00-665 Warsaw, Poland
³ National Fuel Cell Research Center (NFCRC), University of California, Irvine, Engineering Laboratory Facility, Irvine, California 92697-3550, United States

^* corresponding author: konrad.motylinski@ien.com.pl

Abstract

One of the key issues in the energy production sector worldwide is the efficient way to storage energy. Currently- more and more attention is focused on Power-to-Gas (P2G) installations- where excess electric power from the grid or various renewable energy sources is used to produce different kind of fuels- such as hydrogen. In such cases- generated fuels are treated as energy carriers which- in contrast to electricity- can be easy stored and transported. Currently- high temperature electrolysers- based solid oxide cells (SOC)- are treated as an interesting alternative for P2G systems. Solid oxide electrolysers (SOE) are characterized as highly efficient (~90%) and long-term stable technologies- which can be coupled with stationary power plants. In the current work- the solid oxide cell stack was operated in electrolysis mode in the endothermic conditions. Based on the gathered experimental data- the numerical model of the SOC stack was created and validated. The prepared and calibrated model was used for generation of stack performance maps for different operating conditions. The results allowed to determine optimal working conditions for the tested stack in the electrolysis mode- thus reducing potential costs of expensive experimental analysis and test campaigns.