 This paper proposes a new dynamic model for hybrid renewable hydrogen energy systems that can be used to size the components and simulate their real-world behavior. The model takes into account the intermittent nature of solar energy production and the electrolyzer's ability to produce hydrogen on demand. It also accounts for the fuel cell's ability to convert hydrogen into electricity. The model was tested using a university campus case study building in Scotland and compared to a generic model without these features. The results showed that the new model more accurately predicted the performance of the system. This article was authored by Ayatollah Dalyah Ali and Nazni Selami.