Abstract
For over a century, fossil fuels have driven industries and social needs. As the world strengthens its commitment in response to climate change and reducing reliance on fossil fuels, green hydrogen has the potential to be one of the key enablers in the global transition. Solar hydrogen production through electrolysis is one of the most promising methods for harnessing green hydrogen and reducing carbon dioxide emissions. Even though technology has developed at a faster pace in the past years, it still has a long way to be fully commercialised. Current literature shows a significant gap regarding the integration of both technical and economic considerations within a combined framework for modelling solar hydrogen systems, especially in the context of South Africa. This study aims to develop an integrated model for a solar hydrogen system with a focus on optimising the techno-economic aspects looking into different system scenarios. For an overall system architecture, the lowest solar system capacity is obtained in scenario 2, which consists of a polycrystalline PV with a power rating of 3.91 MW and a solid oxide electrolyser, followed by scenario 3 with 4.02 MW however, Scenario 3, which uses monocrystalline solar technology (SunPower X21-335-BLK) along with an alkaline electrolyser was considered as an optimal system. The considered system (scenario 3) offers a good balance between initial capital costs, operational expenses, and hydrogen production costs, making it an attractive solution for large-scale hydrogen production. Scenario 3 has a Levelized Cost of Hydrogen (LCOH) of R37.50/kg, which is 6% less than that of scenario 1. The continuous decrease in the costs of renewable energy has the potential to decrease the unit cost of hydrogen significantly. As the proportion of renewable energy continues to increase in future, hydrogen could offer support that has not been explored within the scope of this project. It presents economic advantages that can impact technical optimisation and LCOH of energy production.