Feasibility of solar hydrogen production studied in Mexico

Liliana García

To calculate Mexico's potential as a producer of hydrogen from solar energy, Valeria Juarez Casildo, a graduate student at the National Polytechnic Institute (IPN), is working on the development of a road map of the entire Mexican Republic, which will allow knowing the productive viability at the national level.

With this study, the Ph.D. student in Energy, from the Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada (CICATA), Queretaro Unit, pretends to lay the foundations for the production, distribution, and use of renewable hydrogen in various applications.

As part of the results obtained, it was determined that Mexico has a production density between 2,250 and 4,933 tons/km2 per year. When analyzing the availability of rainwater as a raw material for hydrogen production, it was found that 26 of the country's 32 states would use less than 12 percent of a year's rainwater to transform solar energy into this energy vector, and at the national level, only six percent would be required.

In this research, it was possible to determine that Mexico's solar hydrogen production potential could cover 10 times the world's demand for this element by 2030.

Hydrogen

Gas is used as a source of electricity, as a raw material in industrial processes, and as a transportation fuel.

One of the best processes for producing hydrogen is from an electrochemical process called water electrolysis in which solar and wind energy is harnessed to transform it into hydrogen, store it and then generate energy.

States with the highest solar hydrogen production

This value is measured in million tons per year (MTon/year). Production in these states represents 59 percent of national production, equivalent to 2,366 MTon/year.

Estado	H2 production [MTon/year] Electrolyzer efficiency=75%.
Chihuahua	443
Coahuila	322
Sonora	316
Durango	186
Zacatecas	130
TOTAL	1,397

Hydrogen production for the entire Mexican territory (unit area in tons/km2 per year). It can be seen that the northern states have greater availability for solar hydrogen harvesting. This map shows a water electrolysis efficiency of 75 percent.
Solar hydrogen production costs. Solar hydrogen production by state and the levelized cost of production for alkaline technology and PEM (Proton Exchange Membrate) technology considering a realistic import scenario.

These results were obtained by processing climatological data measured by weather stations strategically located throughout the country. Thus, an estimate of the energy available to harvest and transform green hydrogen, produced from renewable energies and water electrolysis, was obtained. For these purposes, data mining techniques, Big Data, and geospatial analysis tools were used to establish restrictions in places where it is not possible to produce gas from solar energy, such as protected areas, farmland, and bodies of water, among others.

This paper argues that Mexico could produce solar hydrogen on a large scale at internationally competitive prices with the establishment of a distribution network that would take advantage of existing oil and gas pipelines.

Costs are affected by the importation of the technology, but if Mexico were able to produce solar hydrogen with its own technology, the levelized cost of production could vary between 3.15 and 5.27 USD/kg when produced with alkaline electrolysis and between 4.41 and 7.48 USD/kg if produced with PEM (Proton Exchange Membrate) electrolysis. These results are comparable with the production costs reported by the International Energy Agency (IEA).

Hydrogen is currently considered a clean energy source in several laws in our country, such as the Electricity Industry Law, the General Law on Climate Change, the Federal Electricity Commission Law, the Program for the Development of the National Electricity System (Prodesen/2021-2034), among other federal guidelines.

In addition, the micro scenario of on-site solar hydrogen production is analyzed, with the use of gas station facilities in some of the country's cities. Researchers Ilse Cervantes Camacho, from CICATA Querétaro, and Rosa de Guadalupe González Huerta, from the Escuela Superior de Ingeniería Química e Industrias Extractivas (ESIQIE), advised the polytechnic student on renewable energy, green hydrogen production, data science, and geospatial analysis.