The paper provides an economic model for the assessment of hydrogen production at the site of an existing thermal power plant, which is then integrated into the existing gas grid. The model uses projections of electricity prices, natural gas prices, and CO₂ prices, as well as estimates of the cost of building a power-to-gas system for a 25-year period. The objective of this research is to calculate the yellow hydrogen production price for each lifetime year of the Power-to-gas system to evaluate yellow hydrogen competitiveness compared to the fossil alternatives. We test if an incentive scheme is needed to make this technology economically viable. The research also provides several sensitivity scenarios of electricity, natural gas, and CO₂ price changes. Our research results clearly prove that yellow hydrogen is not yet competitive with fossil alternatives and needs incentive mechanisms for the time being. At given natural gas and CO₂ prices, the incentive for hydrogen production needs to be 52.90 EUR/MWh in 2025 and 36.18 EUR/MWh in 2050. However, the role of hydrogen in the green transition could be very important as it provides ancillary services and balances energy sources in the power system.

This paper presents a new economic profitability model for a power-to-gas plant producing green hydrogen at the site of an existing wind power plant injected into the gas grid. The model is based on a 42 MW wind power plant, for which an optimal electrolyzer of 10 MW was calculated based on the 2500 equivalent full load hours per year and the projection of electricity prices. The model is calculated on an hourly level for all variables of the 25 years of the model. With the calculated breakeven electricity price of 74.23 EUR/MWh and the price of green hydrogen production of 99.44 EUR/MWh in 2045, the wind power plant would produce 22,410 MWh of green hydrogen from 31% of its total electricity production. Green hydrogen injected into the gas system would reduce the level of CO₂ emissions by 4482 tons. However, with the projected prices of natural gas and electricity, the wind power plant would cover only 20% of the income generated by the electricity delivered to the grid by producing green hydrogen. By calculating different scenarios in the model, the authors concluded that the introduction of a premium subsidy model is necessary to accelerate deployment of electrolyzers at the site of an existing wind power plant in order to increase the wind farm profitability.

The production and use of hydrogen are encouraged by the European Union through Delegated Acts, especially in sectors that are difficult to decarbonize, such as the industrial and transport sectors. This study analyzes the possibility of partial decarbonization of the existing plant in the petrochemical industry, with a partial transition from natural gas to renewable hydrogen, as a precursor to the adoption of the hydrogen economy by 2050. This study was based on the example of a plant from the petrochemical industry, namely an existing fertilizer plant. Namely, in the petrochemical industry, hydrogen is produced by steam-reforming natural gas, which is needed in the process of producing ammonia, one of the basic raw materials for mineral fertilizers. By building an electrolyzer at the location of the existing fertilizer plant, it is possible to obtain renewable hydrogen, which enters the ammonia production process as a raw material. The electricity from which hydrogen is produced in the electrolyzer is provided through Power Purchase Agreement contracts concluded with electricity producers from 12 wind power plants. The results of this study show that the production of renewable hydrogen at the location of the analyzed plant is not profitable, but due to the specificity of the process of such an industry, the high consumption of natural gas, and large savings in CO₂ emissions which can be achieved by the production of renewable hydrogen, investment is needed. With a 370 MW electrolyzer, about 31,000 tons of renewable hydrogen is produced, which represents about 50% of the hydrogen needs of the analyzed plant. By producing renewable hydrogen for part of the needs of the analyzed plant, a saving of about 300,000 tons of CO₂ emissions is achieved in relation to the production of gray hydrogen, which contributes to the partial decarbonization of the analyzed plant. The authors are aware that the current market opportunities do not allow the profitability of the investment without subsidies, but with the advancement of technology and a different price ratio of electricity, natural gas, and CO₂ emissions, they believe that such investments will be profitable even without subsidies.