Electrical and gas networks coupling through hydrogen blending under increasing distributed photovoltaic generation

Electricity and gas infrastructure coupling has the twofold effect of solving production-consumption mismatches and decarbonizing the natural gas system through power-to-gas technologies producing hydrogen to be injected within the gas network. However, little is known on how this may impact the gas network operation, especially at a local level. This paper aims to fill this gap by presenting a methodology for modeling the interactions between electricity and gas distribution networks through the implementation of their physical models. A scenario of increasing penetration of distributed photovoltaic production is considered for a sample urban area. Whenever photovoltaic production exceeds the urban area consumption, hydrogen is produced and injected into the gas network. 24 injection scenarios were examined and compared to evaluate their impacts on fluid-dynamics and the quality of gas blends. Results show possible bottlenecks against hydrogen injection caused by the gas network. During summertime operations and in the cases of injection following directly the solar over-production, the hydrogen share peaks 20–30% already in the scenario of 40% solar penetration, generating unacceptable blends. These gas quality perturbations are considerably reduced when hydrogen is injected constantly throughout the day. The choice of the injection node also contributes to perturbation reduction. Sector coupling through hydrogen blending results in a complex interplay between renewable energy excess and local gas network availability which can be enhanced by buffer storage solutions and proper choice of injection node. In the framework of integrated and multi-gas systems, combined simulation tools are necessary to evaluate sector-coupling opportunities case-by-case.