Decarbonisation Technology – August 2021

equivalent CO 2 rejection of power sources • Reduce the quantity of power exported to the grid • Reduce the quantity of power imported from the grid or reduce the size of the hydrogen storage system Simulation results ( Figure 4 ) show that one of the best compromises can be made when we increase the size of the hydrogen storage and solar panels, and integrate smaller wind turbines. Conclusion Using system simulation can help significantly to address the challenges of green hydrogen production. An extensive multi- physics simulation platform is necessary to model complete systems in a single sketch to better size the components involved, evaluate possible architectures, consider a matrix of operating conditions, and improve control strategies. Visual post-processing of results provides a better understanding of the system’s global behaviour and helps

CO rating

100

Energy import

System cost

H storage

Energy export

Direct consumption

Reference architecture Upsizing the wave generator and downsizing wind turbines Upsizing the solar panels and downsizing wind turbines Upsizing the H storage capacity Upsizing H storage, upsizing the solar panels and downsizing wind turbines

Figure 4 Rating different design choices

requires a significant power consumption. Thanks to simulation results, we can evaluate that compressing the gas consumes 6% of the electric power generated by the solar panels, the wind turbine and the wave converter. Using the model, it has also been evaluated that another architecture using two smaller compressors instead of a single one could help to save 1% of this global power production. Depending on the flow of H 2 to be compressed, one or two compressors can be actuated, improving system efficiency. Then, it can be interesting to use simulation to evaluate different design choices and rate them using criteria. Ratings can aim to:

better integrate subsystems, improving the overall performances and ROI. The right design solution can be selected on the first attempt, reducing the risk of errors and accelerating projects. Green hydrogen production is one such application for system simulation. System simulation can, however, be applied to other applications for energy transition: hydrogen distribution using pipelines, high-pressure or cryogenic storage, refuelling stations for FCEVs, fuel cell system integration, combustion engine hydrogen injection, aircraft propulsion systems and others.

Patrice Montaland patrice.montaland@siemens.com

• Reduce the system cost • Reduce CO 2 emissions considering the