  Citation: Butt, M.S.; Shahid, H.; Butt, F.A.; Farhat, I.; Sadaf, M.; Raashid, M.; Taha, A. Power Generation Analysis of Terrestrial Ultraviolet-Assisted Solid Oxide Electrolyzer Cell. Energies 2022, 15, 996. https:// doi.org/10.3390/en15030996 Received: 8 December 2021 Accepted: 26 January 2022 Published: 28 January 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). energies Article Power Generation Analysis of Terrestrial Ultraviolet-Assisted Solid Oxide Electrolyzer Cell Muhammad Salim Butt 1 , Hifsa Shahid 1, *, Farhan Ahmed Butt 1 , Iqra Farhat 1 , Munazza Sadaf 2 , Muhammad Raashid 3 and Ahmad Taha 4 1 Department of Electrical Engineering, New Campus, University of Engineering and Technology Lahore, Lahore 39021, Pakistan; salimbutt@uet.edu.pk (M.S.B.); farhanbutt@uet.edu.pk (F.A.B.); Iqra.farhat@uet.edu.pk (I.F.) 2 Department of Electrical Engineering, FSD Campus, University of Engineering and Technology Lahore, Lahore 38070, Pakistan; munazzasadaf@uet.edu.pk 3 Department of Chemical, Polymer and Composite Materials Engineering, New Campus, University of Engineering and Technology, Lahore 39021, Pakistan; engr_raashid@uet.edu.pk 4 James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK; ahmad.taha@glasgow.ac.uk * Correspondence: h.shahid@uet.edu.pk Abstract: This paper presents a novel system design that considerably improves the entrapment of terrestrial ultraviolet (UV) irradiance in a customized honeycomb structure to produce hydrogen at a standard rate of 7.57 slpm for places with a UV index > 11. Thermolysis of high salinity water is done by employing a solid oxide electrolyzer cell (SOEC), which comprises three customized, novel active optical subsystems to filter, track, and concentrate terrestrial UV solar irradiance by Fresnel lenses. The output of systems is fed to a desalinator, a photovoltaic system to produce electrical energy, and a steam generator with modified surface morphology to generate the required superheated steam for the SOEC. A simulation in COMSOL Multiphysics ver. 5.6 has shown that a customized honeycomb structure, when incorporated on the copper–nickel surface of a steam generator, improves its absorptance coefficient up to 93.43% (48.98%—flat case). This results in generating the required superheated steam of 650 ◦ C with a designed active optical system comprising nine Fresnel lenses (7 m 2 ) that offer the concentration of 36 suns on the honeycomb structure of the steam generator as input. The required 1.27 kW of electrical power is obtained by concentrating the photovoltaic system using In 0.33 Ga 0.67 N/Si/InN solar cells. This production of hydrogen is sustainable and cost effective, as the estimated cost over 5 years by the proposed system is 0.51 USD/kg, compared to the commercially available system, which costs 3.18 USD/kg. Keywords: integration of renewable energy in industry; concentrated photovoltaics; solid oxide electrolyzer cells; thermolysis; honeycomb; absorptance coefficient 1. Introduction The industrial revolution and evolving human lifestyles have resulted in a propor- tional increase in energy demand. Recently, it has been dealt with using conventional as well as renewable energy resources [1]. However, the exhaustive use of conventional or fossil fuel-based resources has created two problems. First, it leads to ozone depletion, and secondly, their usage causes disproportionate greenhouse gas emissions [2]. Among these, fluorinated gases, carbon dioxide, nitrous oxide, and methane pose a greater threat to the survival of the earth’s ecosystem and have a larger impact on the air quality index. It is one of the major challenges of the researchers and policymakers of the 21st century [3,4]. To address the challenges faced by various regions of the earth due to air pollution, the World Health Organization (WHO), the United Nations Environment Program (UN Environment), and the World Meteorological Organization (WMO), with the support of the Climate and Clean Air Coalition (CCAC), are trying their best to deliver services in an integrated and Energies 2022, 15, 996. https://doi.org/10.3390/en15030996 https://www.mdpi.com/journal/energies