A technoeconomic analysis of hydrogen production in a high renewable resources electricity grid using alkaline...

Hydrogen can be a clean energy carrier, the utilization of which can help to reduce emissions and can potentially help in decarbonization of various sectors. The current study presents a technoeconomic analysis of hydrogen production using three electrolyzer technologies-alkaline electrolysis, polymer electrolyte membrane electrolysis and solid oxide electrolysis. The study considers the electricity system of Karnataka, a leader in renewable energy in India. The work considers hydrogen from solar, wind, hydro, mini hydel, biomass and cogeneration sources of electricity as green, that from thermal, net Central Generating Stations (CGS) import (coal) as grey and nuclear as purple. The work presents an analysis of the Karnataka grid for the year 2022. Seasonal variation in electricity and its effect on the amount of hydrogen production is discussed. A detailed discussion on the green and grey hydrogen production costs is presented. When the demand of electricity is less than the maximum electricity that can be generated, excess electricity can be used for hydrogen production. The study presents an approach for quickly estimating the minimum selling price of hydrogen, based on the type of electrolysis. For the conditions considered in the present study, the average cost of grey hydrogen can be obtained to be about Rs. 356, Rs. 326 and Rs. 215 for alkaline electrolysis, polymer electrolyte membrane electrolysis and solid oxide electrolysis, respectively, and green hydrogen, with 10% subsidy, can even be about Rs. 275, Rs. 252 and Rs. 166 for alkaline electrolysis, polymer electrolyte membrane electrolysis and solid oxide electrolysis, respectively. The work points to the possibility of generating green hydrogen in a cost-effective way, by suitable management of the energy grid. This study points to the need for effective grid management strategies for high renewable resource electricity grids, to meet the energy demands, and to achieve carbon neutrality. Suitable electrolysis technologies can be selected, based on Capital Expenditure (CAPEX) and Operation Expenditure (OPEX), and can be operated on cheaper green electricity for clean hydrogen generation.