Citation: Al-Badi, A.; Al Wahaibi, A.; Ahshan, R.; Malik, A. Techno- Economic Feasibility of a Solar-Wind- Fuel Cell Energy System in Duqm, Oman. Energies 2022, 15, 5379. https://doi.org/10.3390/en15155379 Academic Editor: Mario Marchesoni Received: 31 May 2022 Accepted: 29 June 2022 Published: 25 July 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 Techno-Economic Feasibility of a Solar-Wind-Fuel Cell Energy System in Duqm, Oman Abdullah Al-Badi * , Abdulmajeed Al Wahaibi, Razzaqul Ahshan and Arif Malik Department of Electrical & Computer Engineering, College of Engineering, Sultan Qaboos University, P.O. Box 33, Al Khoudh, Muscat 123, Oman; s132379@student.squ.edu.om (A.A.W.); razzaqul@squ.edu.om (R.A.); asmalik@squ.edu.om (A.M.) * Correspondence: albadi@squ.edu.om Abstract: Duqm is located in the Al Wasta Governorate in Oman and is currently fed by 10 diesel generators with a total capacity of around 76 MW and other rental power sources with a size of 18 MW. To make the electric power supply come completely from renewables, one novel solution is to replace the diesel with hydrogen. The extra energy coming from the PV-wind system can be utilized to produce green hydrogen that will be utilized by the fuel cell. Measured data of solar insolation, hourly wind speeds, and hourly load consumption are used in the proposed system. Finding an ideal configuration that can match the load demand and be suitable from an economic and environmental point of view was the main objective of this research. The Hybrid Optimization Model for Multiple Energy Resources (HOMER Pro) microgrid software was used to evaluate the technical and financial performance. The findings demonstrated that the suggested hybrid system (PV-wind-fuel cell) will remove CO 2 emissions at a cost of energy (COE) of USD 0.436/kWh and will reduce noise. With a total CO 2 emission of 205,676,830 kg/year, the levelized cost of energy for the current system is USD 0.196/kWh. The levelized cost for the diesel system will rise to USD 0.243/kWh when taking 100 US dollars per ton of CO 2 into account. Due to system advantages, the results showed that using solar, wind, and fuel cells is the most practical and cost-effective technique. The results of this research illustrated the feasibility and effectiveness of utilizing wind and solar resources for both hydrogen and energy production and also suggested that hydrogen is a more cost-effective long-term energy storage option than batteries. Keywords: hydrogen production; renewable energy; wind turbines; PV; fuel cell; batteries 1. Introduction The Oman Investment Authority started to invest in green hydrogen plant productions. It announced four projects with a total capacity of around 30 gigawatts (GW) of renewables to support green hydrogen production [1]. The Al Wusta and Dhofar governorates will be the sites of these projects. The excellent wind and solar resource availability in both areas is anticipated to lower the net levelized cost of energy and, as a result, the levelized cost of hydrogen, which will become very competitive in Oman. The biggest one (the Gio project) will be powered by 25 GW of wind and solar energy [2]. It will be located in the Al Wusta governorate with a total investment of USD 30 bn. Construction is planned to start in 2028. The Gio project will be built in stages and will reach its full capacity by 2038. The second project, Hyport Duqm, will be located in Duqm, Al Wusta, with a total capacity of 1.3 GW and is expected to produce 1 million metric tons per annum of green ammonia when it fully operates [3]. The third and fourth projects will be in the Dhofar governorate with around 3 GW capacity. Renewable energy systems are typically used with backup power production, such as diesel generators or batteries, for off-grid applications because of the intermittent nature of renewable energy sources and their low reliability. Due to the fluctuating cost of fuel Energies 2022, 15, 5379. https://doi.org/10.3390/en15155379 https://www.mdpi.com/journal/energies