Green hydrogen production in a south of Italy region using excess electricity only: real scenario and alternatives

Stating the European Union decarbonisation objectives setting carbon neutrality by 2050, this article proposes a thorough analysis of alternative energy system scenarios deriving firstly from the hypothetical switch-off of a coal-fired power plant, secondly from the the contextual introduction of Hydrogen Valleys' electrolysers, thirdly from the increase in the peak photovoltaic power matching the switched-off power plant annual energy production. Hydrogen generation, carbon dioxide and excess electricity production as well as grid stabilization are the main investigated aspects. After a brief description of the methodology based on the use of the freeware EnergyPLAN model, authors describe the reference as well as alternative considered scenarios. Main results obtained start from annual CO2 emission and power plant production analysis continuing with the description of electrical grid demand/production imbalance arising if a variable renewable energy source higher production level is introduced. The role of electricity storage thought as the coupling of electrolyser and hydrogen fired gas turbine is then investigated. The total hydrogen production potential based on the use of the solely excess electricity production is determined. The mean monthly power plant, renewable sources and total productions are compared with the demand curve arguing that power plants mostly contributes to the shape of production curve whereas renewable energy sources contribute to increase the total production level so to reach the actual demand values. Lastly, a grid stability constraints analysis ends the proposed results.