Optimisation Under Uncertain Meteorology: Stochastic Modelling of Hydrogen Export Systems

Deriving accurate cost projections associated with producing hydrogen within the context of an energy-export paradigm is a challenging feat due to non-deterministic nature of weather systems. Many research efforts employ deterministic models to estimate costs, which could be biased by the innate ability of these models to �see the future�. To this end we present the findings of a multistage stochastic model of hydrogen production for energy export (using liquid hydrogen or ammonia as energy vectors), the findings of which are compared to that of a deterministic programme. Our modelling found that the deterministic model consistently underestimated the price relative to the non-deterministic approach by $ 0.08 � 0.10 kg-1(H2) (when exposed to the exact same amount of weather data) and saw a standard deviation 40% higher when modelling the same time horizon. In addition to comparing modelling paradigms, different grid-operating strategies were explored in their ability to mitigate three critical co-sensitive factors of the production facility: high-cost hydrogen storage, uncertainty in weather forecasting and sluggish production processes. We found that a �grid-wheeling� strategy substantially reduces the production cost for a solar system (by 16% and 21% for LH2 and NH3, respectively) due to its ability to guarantee the return of energy borrowed overnight during the day, but was not effective for the wind system, due to the non-periodic nature of aeolian weather patterns.