Hydrogen-Blended Natural Gas in a Distribution Network - An Italian Case Study Analysis

Hydrogen has come to play a critical role in decarbonizing the energy sector with the effective use of renewables, making it a more attractive green transition pathway. Blending H2 to existing natural gas networks in an urban context is directed at reducing the CO2 emissions associated with the thermal load in buildings. In this study, a natural gas network modelling and steady-state simulation is carried out using GasNetSim on an actual network subsection to characterize the flow parameters, such as pressure and volumetric flow rate and gas quality for a tree topology distribution network. Distribution side networks are short distance, meshed and composed of different topologies. In this study, for a tree topology network blending of more than 13.5% of H2 does not meet the gas quality limits of the distribution network according to Italian regulations. Further in the study peak and off-peak conditions of user demand are simulated to understand the maximum and minimum variations in the flow properties. The maximum pressure drop due to H2 blending is in the range of 0.4% which enables further simplification of complex pipeline network studies as the hydrogen composition is practically uniform throughout the nodes.