Scale-up analysis and exergoeconomic assessment of large scale photo-catalytic hydrogen production plants

• Scale-up analysis of a dual cell photo reactor based on radiation model is performed.
• A 10 times increase in light intensity leads to a fivefold hydrogen production rate.
• The hydrogen production capacity has a strong dependency on exergetic losses.
• A maximum hydrogen exergy price of 2.12 for production capacity of 1 ton day−1 can be achieved.

In this paper a scale-up analysis of a dual cell photo reactor based on a kinetic, radiation model and mass balance of reactants is presented. A kinetic model that includes phenomenological based parameters is developed to evaluate the reaction rate under operational conditions of a photo-reactor. The analysis is performed for six different scale-up ratios with three different constraints for each case. With a constraint of pre-determined length to diameter ratio factor, a lower enhancement in productivity can be achieved at higher light intensities. The analysis is followed by an exergoeconomic study in which two case scenarios of a hydrogen production plant with and without oxygen production for three different production capacities are considered. It reveals the maximum hydrogen exergy price of 2.2, 0.88, and 0.51 $ kg−1 for production capacities of 1, 100, and 2000 ton day−1, respectively.