Hydrogen for Electricity: Technical and Normative Preliminary Analysis

Hydrogen is an energy vector that could help reaching the CO2 neutrality before 2050. It has a very high potentiality to be exploited in many sectors such as automotive, energy production and storage. Hydrogen has an elevated energy density per unit of mass (much higher than the natural gas one), it does not produce pollutants (when it is used in electrolyser it allows to generate only electricity and water), it has a very low volume energy density. The hydrogen storage sector is the main topic of this study: an easily movable plug-in system is designed inside a container to use the additionally electricity produced with renewable sources – when the available generated power is higher that the load demand – to generate gaseous hydrogen in electrolyser that will be compressed until almost 700bar, stored in very high-pressure tank, and converted, whenever is needed, in electricity using a 15kW fuel cell stack. In particular, the purpose of this Paper is the analysis of the components contained in the system (15kW), with a focus on the electrolyser and fuel cell technologies, and a market analysis of the whole elements necessary in this type of system. Moreover, standards and national Directives related to hydrogen are proposed to better explain what is needed by this technology to spread and ATEX Directive is explained in relation with hydrogen use. Efficiencies of the whole system are computed with design parameters in the case of combined heat and power generation, obtaining that it is possible to recover about one fifth of the power inlet in the system. Finally, a qualitative analysis is presented where the performances of the whole system (from the renewables’ electricity consumed to produce hydrogen until the electricity generated using hydrogen) are showed related to the variation of the main operative factors: temperature, pressure and humidity.