Electrolysis is the process of decomposition of the liquid, containing ions by passing electricity through it. This process is achieved by an electrolyzer. An alkaline water electrolyzer uses electrical energy to break the chemical bond between hydrogen and oxygen in an alkaline electrolytic medium. The performance of the electrolyzer depends upon various parameters like temperature, pressure, ohmic overpotential, activation overpotential, etc. In this study, various parameters that affect the performance of the electrolyzer are identified and integrated using fundamental thermodynamics and electrochemical equations. A mathematical model is created in MATLAB/SIMULINK to analyse the voltage vs current density plot of the electrolyzer. An attempt is made to optimize the performance of the electrolyzer through the variation of the parameters. It was observed that increasing the operating temperature and decreasing the operating pressure favours the electrolysis process. Also, 30 wt% of KOH solution as electrolyte exhibits the optimal cell voltage as compared to 20 and 40 wt% solutions.

Electricity backup systems are needed to address the temporary grid failure, short-term electricity supply at the locations without grids, power surges, and massive blackouts. These power backup technologies include a combination of batteries and generators operating mostly on fossil fuels. Concerns regarding instant start capability with generators, noise, and mainly due to carbon emissions have encouraged to look for alternatives with low carbon technologies based on renewable energy sources. Stored electricity from solar, wind and other renewable sources are emerging and cost-competitive alternatives to fossil fuels-based power backup systems. Due to the high energy density, unlimited production source, and easy storage and transportation, hydrogen is emerging as an effective and efficient energy carrier and its applications for an alternative to power supply systems. Hydrogen produced from the electrolysis of water by renewable electricity makes it green and has minimum carbon emissions among the other alternatives and operates in real-time startups with no mechanical noise. Fuel cell is a growing technology and has the potential to channelize hydrogen energy as an alternative to carbon-intensive power supply systems. In a fuel cell, hydrogen combines with oxygen and produces electricity. The fuel cell is a robust design with several parameters that control its operation and capacity. This paper identifies the parameter-based modeling approach to establish a connection of power demand with hydrogen production. A mathematical model for system sizing of hydrogen production and fuel cell for re-electrification for a reference case is developed.