Brazil is making an effort to enter the global map of H2V (H2 for hydrogen and V for green) production, a clean fuel with potential to meet demands of the electrical and automotive sectors with low environmental impact.

By the end of this year, EDP Brasil, one of the leading companies in the energy sector in the country, plans to start activities in a pilot plant for H2V production in São Gonçalo do Amarante, in the state of Ceará. The hydrogen will be obtained through water electrolysis, a chemical process that uses electric current to break down water into its constituents, hydrogen (H, forming H2) and oxygen (O, forming O2), which exist in the water molecule (H2O).

When the electrolysis process employs renewable energy sources, such as wind, solar, or biomass, the hydrogen is classified as green. EDP’s plant will use photovoltaic energy and will have the capacity to produce 22.5 kilograms (kg) of hydrogen per hour. The estimated investment is R$41.9 million.

Often pointed out as the fuel of the future, hydrogen has a high calorific power, almost three times higher than diesel, gasoline and natural gas. When transformed into energy – fueling a combustion engine or in any other application – it does not emit greenhouse gases (GHG). The residual hydrogen released into the atmosphere, in contact with oxygen, results in water vapor.

The most abundant element in the universe, hydrogen is rarely found in isolation on Earth, but is present in numerous compounds, including water, fossil fuels, and different types of biomass. Obtaining the gas in these cases depends on the processes involved. The most common of these is steam reforming, a chemical reaction of hydrocarbons, commonly natural gas, with water. The hydrogen produced this way is called gray, since its conversion process releases CO2 into the atmosphere, or blue, when the carbon dioxide gas generated during its production is captured and geologically stored.

The green hydrogen produced at the pilot plant in Ceará will be used to replace part of the mineral coal that supplies the Pecém Thermoelectric Plant (UTE Pecém). “It is a research and development [R&D] project that will allow us to understand the energy gain provided by hydrogen, with energy power more than four times higher than that of coal,” says Cayo Moraes, operations manager at EDP.

The H2V pilot plant will also allow the company to observe the technical, regulatory and economic feasibility of fuel production. The expectation is that the unit will provide the necessary subsidies for the decision on the implementation of an industrial scale plant in the state. In this case, the hydrogen could be exported to European energy companies, generate vehicle fuel, or supply industrial companies.

The project is seen by energy sector specialists as the first of a series of initiatives aimed at producing green hydrogen in the country. The government of Ceará alone already has 14 memorandums of understanding with private groups interested in producing the fuel in the state. “Maybe not all of them will become feasible. But if half of the agreements become effective, we will have the equivalent of an Itaipu in operation in Ceará between 2025 and 2030,” states Roseane Medeiros, executive secretary for Industry of the Secretariat of Economic Development and Labor of the State of Ceará (Sedet). The Itaipu hydroelectric plant, the largest in the country, has an installed power of 14 gigawatts (GW).

Rio Grande do Norte, Piauí, Pernambuco, Bahia, Minas Gerais, Rio de Janeiro and Rio Grande do Sul also report having signed memoranda with energy generating groups. The race to attract green hydrogen production projects is global. Chile, Japan, Germany, Holland, United States, South Korea, Australia and China are some of the countries that announced national programs to stimulate technological development and H2V production.

There are 520 hydrogen plant projects in the world, according to the Hydrogen Council, an association that brings together representatives of the largest producers of this gas. If confirmed, they will demand investments of US$ 160 billion.

The association estimates that the fuel production will exceed 600 million tons per year (mt/year) and account for 22% of the world energy demand in 2050, which would allow a 20% reduction in GHG emissions worldwide. The projections of the International Renewable Energy Agency (Irena) are more modest. For it, the sector will produce 409 mt/year in 2050, which will respond, in the entity’s calculations, for 12% of the global energy demand.

Currently, the hydrogen contribution in the world energy matrix is very small. Practically all the hydrogen produced, a little more than 100 million tons annually, is used for chemical purposes in industrial processes, such as petroleum refining, fertilizer production, steel mills and the chemical industry.

Experts predict that the predominant H2V production process in the coming years will be water electrolysis – the same proposed for the pilot plant in Ceará. This method will be obtained mainly by plants equipped with electrolyzers (equipment responsible for the electrolysis process) supplied by renewable energy sources, ensuring that the entire process is GHG-free (see infographic).

One of the main barriers for a greater offer of green hydrogen in the world is the need for technological maturity gains in the hydrogen production chain, according to the report “Geopolitics of the energy transformation: The hydrogen factor”, released by Irena in January. Another is the high production and logistical costs.

According to the International Energy Agency (IEA), the cost of a kilogram of gray hydrogen is just over US$1 – which makes it competitive with natural gas. Blue hydrogen costs an average of US$2.3 per kilo. A kilo of green hydrogen is between US$3 and US$8, depending on the energy source used and the region of the world where this energy is produced. Irena expects that the expansion of renewable energy supply in the world and gains in production scale will make green hydrogen competitive with blue hydrogen in 2030 and, over the next decade, production costs will approach those presented by gray hydrogen.

According to the National Energy Expansion Plan (PDE 2031), prepared by the Energy Research Company (EPE), an institution linked to the Ministry of Mines and Energy, Brazil has conditions to produce green hydrogen cheaper than the international average. The estimated cost of H2V – since there is still no effective production – is between US$ 2.2 and US$ 5.2 per kilo in the country.

“The popularization of hydrogen will happen out of necessity. We are living an environmental emergency and the world has already realized that it is no longer possible to depend on fossil fuels to generate electricity and fuel vehicles,” says engineer Paulo Emílio Valadão de Miranda, director of the Hydrogen Laboratory of the Alberto Luiz Coimbra Institute for Post-Graduate Studies and Research in Engineering of the Federal University of Rio de Janeiro (Coppe/UFRJ) and president of the Brazilian Hydrogen Association (ABH2).

An opportunity to reduce hydrogen production costs is to increase the efficiency of electrolyzers. Researchers at the Center for Functional Materials Development at the Federal University of São Carlos (CDMF-UFSCar), one of the Centers for Research, Innovation and Dissemination (Cepid) funded by FAPESP, study materials capable of reducing energy consumption in the chemical process of decomposition of the water molecule. As explained by the chemist Lúcia Helena Mascaro Sales, research director of the project, one of the best catalyst materials – substances that increase the speed of chemical reactions in electrolysis – are the noble metals, especially platinum. Nickel, cobalt, or molybdenum can also be used associated with iron alloys or as sulfides with great performance.

The UFSCar team researches the use of materials such as titanium oxide modified with molybdenum sulfide or different alloys composed of nickel, copper, molybdenum and iron. “On a laboratory scale, we have demonstrated that it is possible to significantly reduce energy consumption in water electrolysis,” says Mascaro. The Anglo-Dutch oil company Shell, a co-sponsor with FAPESP in another research project in which Mascaro participates, on energy-dense carriers, is interested in testing the catalysts developed in pilot plants in Amsterdam, in the Netherlands, and in Houston, in the United States.

At the Federal University of Ceará (UFC), Professor Adriana Nunes Correia, from the Department of Analytical Chemistry and Physical Chemistry, also investigates metallic materials capable of increasing the efficiency and reducing the costs of electrolyzers. The research proposal, still in its initial phase, is to use microbial electrolysis cells, employing microorganisms as biocatalysts, to produce hydrogen from domestic sewage or industrial effluents. The idea is to transform the sewage’s chemical energy into electric current, which makes it possible to obtain the gas. “The process would make it possible to produce hydrogen and simultaneously treat organic waste,” Correia says.

Research focused on green hydrogen is also being done at the Federal University of Paraná (UFPR). The chemist Helton José Alves, coordinator of the Materials and Renewable Energy Laboratory, is dedicated to the study of new technological routes for the production of the fuel. One of them uses acidogenic bacteria to degrade residual biomass from industrial effluents.

The research resulted in the publication of two articles in the International Journal of Hydrogen Energy. The papers address the production of hydrogen from brewery wastewater. “The great advantage is to reduce production costs and save water resources,” says Alves. The production process would be indicated for the production of hydrogen as an energy solution for the industry itself where the effluent is generated.

Another path studied for hydrogen production is to use the method known as dry reforming of biogas. Alves explains that the system foresees the use of methane and carbon dioxide present in the biogas to generate synthesis gas, a mixture of hydrogen and carbon monoxide. The process occurs in reactors with nickel-based metal catalysts at a temperature between 700 and 800 degrees Celsius. Subsequently, the synthesis gas is purified to obtain hydrogen. “Together with partners, we intend to install a pilot unit capable of producing 1 kg of hydrogen per hour still in 2022,” anticipates Alves. Unlike the conventional natural gas steam reforming system, the dry system does not require water.

The study of hydrogen production routes that do not depend on pure water in their processes is of great relevance and is closely followed by professionals in the sector. According to Irena, to produce 409 million tons per year of green hydrogen and supply 12% of the world’s energy demand in 2050, it will require the consumption of somewhere between 7 billion and 9 billion cubic meters of water per year. The total is less than 0.25% of today’s fresh water consumption. This may not sound like much, but it is an impressive volume in a world where this resource is becoming scarce.

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