Hydrogen is a clean and environmentally friendly energy vector that can play an important role in meeting the world’s future energy needs. Therefore, a comprehensive study of the potential for hydrogen production from solar energy could greatly facilitate the transition to a hydrogen economy. Because by knowing the exact amount of potential for solar hydrogen production, the cost-effectiveness of its production can be compared with other methods of hydrogen production. Considering the above, it can be seen that so far no comprehensive study has been done on finding the exact potential of solar hydrogen production in different stations of Iran and finding the most suitable station. Therefore, in the present work, for the first time, using the HOMER and ArcGIS softwares, the technical-economic study of solar hydrogen production at home-scale was done. The results showed that Jask station with a levelized cost of energy equal to $ 0.172 and annual production of 83.8 kg of hydrogen is the best station and Darab station with a levelized cost of energy equal to $ 0.286 and annual production of 50.4 kg of hydrogen is the worst station. According to the results, other suitable stations were Bushehr and Deyr, and other unsuitable stations were Anzali and Khalkhal. Also, in 102 under study stations, 380 MW of solar electricity equivalent to 70.2 tons of hydrogen was produced annually. Based on the geographic information system map, it is clear that the southern half of Iran, especially the coasts of the Persian Gulf and the sea of Oman, is suitable for hydrogen production, and the northern, northeastern, northwestern, and one region in southern of Iran are unsuitable for hydrogen production. The authors of this article hope that the results of the present work will help the energy policymakers to create strategic frameworks and a roadmap for the production of solar hydrogen in Iran.

In this study, the effect of the presence of horizontal fins on the safe operating time (SOT) of the PCM filled heat sink was examined. The effects of the number of horizontal fins, as well as fins length on SOT at different aspect ratios, was investigated. Horizontal fins, owing to their high thermal conductivity, cause uniformity in temperature distribution and improve the heat sink thermal conductivity (positive effect). Incorporating horizontal fins reduces the PCM volume fraction which consequently diminishes the ability of the heat sink to absorb the thermal energy (negative effect). The competition between the former effect and the latter determines the efficacy of adding horizontal fins in the PCM filled heat sinks. As the number of horizontal fins increases up to five, the positive effect is superior to the negative one which in turn enlarges the safe operation time. By the further increase in the number of fins, the negative effect prevailed over the positive effect and therefore the safe operation time diminished. As the heat sink aspect ratio increased, convection heat transfer efficacy becomes more apparent. In this case, it is recommended to use horizontal fins with shorter lengths so that the PCM movement is not disturbed.