What is green hydrogen?

On the way to decarbonizing the planet, green hydrogen could be the greatest ally of the human species. With three times the energy potential of gasoline, this fuel can get cars and industries moving without releasing a single molecule of carbon dioxide.

However, a lot of scientific research is still needed to realize the promise of a cleaner future. And for that, Brazil is starting to take its first steps by betting heavily on biomass and solar energy.

How is hydrogen used?

Hydrogen is a gas formed by the element of the same name. Just like the CNG we use in cars, it can be burned to start engines or generate electricity.

Thiago Lopes, professor and researcher at USP (University of São Paulo), explains that its biggest advantage is that it does not emit carbon dioxide, which is one of the main culprits of greenhouse effect and global warming during combustion. But the problem is getting it.

If there are no emissions during use, pollutants may be released during the production of this fuel from the traditional method of natural gas or mineral coal. This hydrogen is classified as gray.

700 million tons of fuel is burned annually in the world. To stop global warming, methods were developed to capture the gases released during production, and the term less harmful blue hydrogen emerged.

But the measures are still not enough to promote the full protection of the environment. Production is driven by the still limited use of fossil fuels.

Therefore, new ways of obtaining hydrogen from renewable-only sources, classified as green, were sought.

Hydrogen gas can be produced basically in two different ways. The most traditional way is to convert methane through a chemical reaction known as steam reforming.

It is also possible to produce green hydrogen from sources such as biomass, which is considered renewable. Another advantage of its use is that it helps to remove some of the carbon from the atmosphere during cultivation.

This is Lopes’ claim. The researcher wants to take advantage of Brazilian sugar cane, an industry in which the country is a world leader. According to him, this vegetable is a complete source of resources that can replace fossil fuel reserves.

However, it is already possible to generate electricity from ethanol and biodiesel and residual pulp. Now the scientist is looking for ways to produce hydrogen from this strategic source for the country.

Lopes says that last year, the Brazilian government and private investors finally turned their attention to the technology. Lopes argues that relying on the country’s strongest possession is the best way to use new resources.

How is green hydrogen produced?

In recent years, a second form of hydrogen production has attracted attention: electrolysis reactions. It has been known to scientists for decades, but with the latest technological advances, it has begun to be used in an economically competitive way.

By using electrodes made of noble materials such as platinum and applying an electric current through water, it is possible to produce gas without releasing carbon into the atmosphere.

However, one of the questions in the use of this method is related to the source of the electrical energy used, because electricity generation by burning oil, natural gas and coal is still widely used in the world.

Francisco Feitosa, an electrical engineer and doctoral student at the Federal University of Minas Gerais, says Brazil has what it takes to overcome this contradiction. First, the main form of electricity generation in the country is hydroelectric power plants, which are considered renewable sources.

But we can go further, according to the researcher. The national region has a huge solar potential, which Feitosa discovered in his research, for example. It is developing a station model for green hydrogen production that could fuel adapted vehicles.

The engineer explains that these stations can be used along highways and create a sustainable road corridor. Hydrogen-powered cars already exist in the United States, Japan, and Germany. And they can happen in Brazil.