In parallel, research is trying to find other ways to produce green hydrogen. The director of ABH2 cites the use of biomass, whose biodigestion results in biogas.
It is then worked to remove substances such as sulfur and then heat is used to obtain hydrogen. Another method removes sulfur and other impurities and refines the resulting biogas into biomethane, which is then steamed into green hydrogen. According to Monteiro, this process would cost less than electrolysis.
Biomass and photocatalysis
To also try to make the industrial production of green hydrogen feasible, Turiya Renováveis, a renewable energy generation company that is part of Indra Energia, a commercialization company in the sector, and the Federal Institute of Education, Science and Technology of Ceará (IFCE) joined forces to produce green hydrogen through the photocatalysis method. “Our proposal is to contribute to the development of technologies that make it feasible to obtain green hydrogen in Brazil, to be used as another alternative renewable source,” says Ingrid Santos, CEO of Turiya.
The project studies the use of sunlight to activate a catalyst, which would then act in the separation of the water molecule. According to Bruno César Barroso Salgado, PhD, coordinator of the Renewable Energy Graduate Program at IFCE, the most studied substance as a catalyst is titanium dioxide – a material of easy access and low cost. At the same time, he envisions mixing glycerin to water. “This increases the production of hydrogen and ends up bringing a cycle of sustainability. We take advantage of a biomass residue (glycerin as a byproduct of biodiesel), together with solar radiation, leading to a practically zero energy production cost (because no electricity is required). The process becomes very attractive from this point of view,” he says.
The study foresees that the catalyst will be impregnated in the photocatalyst plate. “The project is in the phase of finding engineering that favors this mechanism,” says Barroso. The pilot phase of the project will occur when the analyses indicate the best substance for this purpose. And there is no deadline yet.
The professor emphasizes that photocatalysis does not replace electrolysis. “The engineering behind photocatalysis today is not competitive enough to defeat electrolysis as a method of producing hydrogen. In fact they are complementary methods”, he affirms, reminding that photocatalysis projects should be installed in areas of greater solar radiation.
With so many variables involved in the process of obtaining green hydrogen, it was not by chance that the CCEE decided to develop a certification project. “Whoever is buying this hydrogen needs to be sure that the production is not bringing with it a carbon footprint. So, certification is a crucial element to ensure the main goal of this energy source, which is decarbonization,” says Gedra, from CCEE.
According to the entity’s president, Rui Altieri, by the end of this year an initial version of the certification will be available, which is also being discussed by a national group within the Brazilian National Electricity Production and Transmission Committee CIGRE-Brazil.
To obtain the CCEE’s stamp of approval, there is already a consensus that a hydrogen plant must, along with the construction of the plant, make feasible the construction of an electric power plant, which will supply additional clean and renewable electricity in the same amount as the one consumed by the hydrogen plant.
According to Altieri, the role of the CCEE, as an “exempt entity” gives it credibility in this process. “The energy purchase and sale contracts, because of the Brazilian legislation, have to be registered in the CCEE, followed up by it and, mainly, settled here in the CCEE,” he says.
The entity will take the discussion to the Cigre international meeting, in August, so that the certification has international parameters. The goal is to seek the consensus of all stakeholders in the green hydrogen area, especially Europe, which is more advanced in this process. “So, we are seeking to define attributes that meet what is under discussion in the world. Thus, when the exported hydrogen reaches Germany, or another country, our certificate will be aligned to an international standard, and will be recognized as being produced without a carbon footprint,” says Altieri.