Opinion – Rodrigo Tavares: The way Brazil produces biofuels is risky, says Portuguese expert

He is one of the most respected European scientists in clean energy. From his laboratories at the University of Porto, in the north of Portugal, where around 60 doctoral students and doctoral researchers work, the Full Professor of Chemical Engineering Adélio Mendes develops innovative technologies in photovoltaic cells, electrochemical and photoelectrochemical reactors, batteries and fuel production. synthetics.

It holds dozens of patents and is supported by several European Union programs to develop disruptive methods of producing electricity with greater environmental benefits and better commercial potential.

On the possibility of one day being awarded the Nobel Prize in Chemistry, as is discreetly discussed in academia, Portuguese Adélio Mendes does not want to comment. On a guided tour of the Faculty of Engineering, he preferred to talk about everything else.

This lab has been a factory of innovation. What are the main achievements?

Over the years we have been able to make advances and some have ended up gaining some notoriety. For example, we invented a new worldwide process for the production of alcohol-free beer, which began to be marketed about 15 years ago by a Portuguese brewer, based on a process called “pervaporation”. We also create cork stoppers for white drinks, preventing the drink from darkening. In addition, we have developed a new water-based paint with special anti-corrosion properties for covering bridges.

We have more recently developed a laser-assisted glass cell welding process using glass frit. It’s a unique process. I am also pleased that we were able to develop a hydrogen purification process that has the ability to effectively remove carbon monoxide and therefore lower the costs of hydrogen purification whether it is biofuel, biomass or fossil fuel reformation. .

What are you working on at the moment?

We are currently working on two absolutely disruptive projects. One is the decomposition of methane into hydrogen and coal, without producing CO2. This process is the cheapest way to produce hydrogen, it is much cheaper than fossil hydrogen. And if it is produced from biomethane from biogas it is even cheaper. We call this type of hydrogen “bright hydrogen” because it not only produces hydrogen without CO2 emissions, but we also remove CO2 from the atmosphere. That is, biomass captures CO2 from the atmosphere, we ferment the biomass and produce methane.

By transforming this methane into hydrogen and coal we are imitating what nature has done in the past, we are humanly reproducing the natural process of transforming CO2 from the atmosphere into large reserves of coal. It’s a very disruptive process. There are already some companies working on similar processes, but at extremely high temperatures and not adaptable to the mobility sector. What we are developing is extraordinary because we are achieving more than 10 kW of power per litre.

And the second project?

The second development is a little later. It is the electrochemical conversion of CO2 into organic molecules and, in particular, into fuels. This is already done in other laboratories, but we have discovered how to greatly increase the selectivity of the reaction, that is, our ability to produce only what we want, avoiding the production of by-products.

Which until now had not been discovered. And with high current density. We are currently validating these developments experimentally. We have already filed a patent. But we continue to work on confirmations and we hope, very soon, to file a second patent and launch a spin-off company in this area to accelerate the development of this technology.

How many spin-offs have you created?

Seven.

It is also developing other projects in methanol and ammonia. Why are they innovative?

In 2018 I realized that in order to have green fuels, with commercial sustainability, we should not bet on synthetic methane, which has a very high cost, but on methanol.

It was a bold gamble at the time. I managed to convince important national companies. We have developed a methanol production process that is not only competitive compared to fossil methanol, but also has very high growth potential. What we basically do is capture CO2 directly from the paper and wood industry, which is a much cheaper capture than buying fossil CO2 or capturing CO2 from the atmosphere. As a result, we were able to produce methanol at a cost of approximately 500 euros (R$ 2,980) per ton. At the moment, and without paying taxes on CO2 emissions, fossil methanol is valued at 505 euros (R$ 3,010) per ton, that is, we are in the leadership of green fuels.

And the ammonia?

It is a project for the renewable production of ammonia. We are aware that our renewable version is still a little more expensive than the fossil version, but it has the potential to make a profit as soon as the situation is more favorable, not only in terms of the price of electricity, but also in terms of taxes on CO2. We think that five years from now we can reach breakeven and make the solution commercially viable.

Brazil is an outstanding leader in the production of biofuels. What are the opportunities and risks of this sector?

I would start with the risks. Biomass, such as sugar cane or corn, incorporates mineral micronutrients that, when burned, often end up being destroyed, phosphorus is lost, selenium is lost, potassium is lost. Alternatively, the most sustainable way, or one of the most sustainable ways to produce bioenergy is from the anaerobic digestion of biomass, producing biogas. Why? Because biogas contains CO2 which is highly valued for various applications, namely it can be converted into biofuels. And it produces biomethane, which currently has a price roughly equal to that of natural gas. It also produces a fertilizer, which completely recycles the minerals that have been extracted, keeping them bioavailable.

Therefore, I place a lot of emphasis on biogas as one of the most sustainable forms of bioenergy production. Everything that is burning or gasification implies the destruction of soils in addition to destroying biodiversity. I understand that it is necessary, very quickly, to stop producing biofuels as we are doing, namely ethanol.

And what about opportunities in Brazil?

There are certainly opportunities in photovoltaics. It is necessary to cover the photovoltaic cities. The new photovoltaic technology, which is a hybrid between silicon and perovskite, allows energy conversions with 30% efficiency. We have increased the current state of the art by about 50%. I would like to challenge a country as relevant as Brazil to also look at offshore wind farms whose technology was born from oil platforms. It is a technology that is worth betting, it will lower the cost.

It is also necessary to bet on floating photovoltaic, taking advantage of the hydrographic basins of the dams. Brazil has many important water reserves that could be used to install floating photovoltaic systems to produce electricity. It is one of the cheapest ways to produce electricity. It is cheaper to produce a kilojoule of energy using photovoltaics than to use a kilojoule of energy to produce ethanol.

Have you had Brazilian students?

Yes, some. One thing that strikes me is that most Brazilian students who come to Portugal want to stay in Portugal or Europe. Most of my Brazilian students showed no interest in returning. Sad for Brazil, happy for us.