Techno-economic analysis of green hydrogen production in Saudi Arabia: A comparative study of solar PV and CSP technologies

Hydrogen is crucial in increasing the adoption of intermittent solar technologies including concentrated solar plants (CSP) and Photovoltaic (PV) panels due to its versatility and potential for long–term storage. This study conducts a techno-economic analysis of the green hydrogen supply chain powered by solar energy in Dhahran, Saudi Arabia. It compares different configurations of a CSP tower, PV, and hybrid PV-CSP system to power a 1 MW solid oxide water electrolyzer cell (SOEC) for green hydrogen production. The results indicate that the PV plant outperforms the CSP tower plant, achieving a lower levelized electricity cost of 5.33¢/kWh versus 8.54 ¢/kWh. Due to lower levelized electricity costs, the levelized cost of hydrogen production is also lower for PV at 4.23 $/kgH₂, compared to 4.95 $/kgH₂ for the CSP plant, while the hybrid system of PV and CSP leads to a production cost of 4.57 $/kgH₂. However, the CSP tower system has lower lifecycle GHG emissions of 10.8 gCO_2eq/kWh compared to 35.4 gCO_2eq/kWh for solar PV and requires a lower land area at 0.75 m²/MWh as compared to 1.04 m²/MWh for PV. The transition to solar PV or solar CSP tower systems can also lead to a substantial reduction in CO₂ emissions during the operational lifetime by a maximum of 3.65 million tons for fuel-oil plants and 3.22 million tons for natural gas plants, resulting in carbon credit gains of $ 22.9 million and $ 20.2 million, respectively. The sensitivity analysis indicates that the cost of hydrogen (LCOH) is highly responsive to changes in Capital Expenditure (CAPEX) and Cost of Electricity (LCOE). A 20% increase in CAPEX leads to a 14.8% rise in LCOH for the PV scenario, while a 20% increase in LCOE results in an 8.9% increase in LCOH for the CSP scenario. Conversely, the LCOH exhibits low sensitivity to changes in the inflation rate and discount rate, with increases of up to 20% causing only minor fluctuations in LCOH, peaking at 2.03% for the PV configuration and 2.9% for the CSP configuration.