The definition “green hydrogen” is a footprint of frequent use but is rarely made explicit. As an energy source, in which cases is hydrogen NOT green? The problem is that it is not found in the free state in nature, and to obtain it you have to deal with the molecules that contain it. For example, it is possible to split hydrocarbon molecules (but in this way CO2 is released) or use other chemical processes, which however, taking the total account, almost always give a negative balance for the environment. Even the electrolysis of water, which produces hydrogen and oxygen, is not green if energy from non-renewable sources is used to obtain it. We must therefore ask ourselves the problem of creating completely clean hydrogen technologies. And that they also cost little, otherwise they are not competitive.
The European project PROMETEO, coordinated by ENEA (the Italian agency for new technologies, energy and sustainable development) aims to reduce the production costs of green hydrogen, to less than 2 € / kg in perspective, thanks to a highly efficient technology that combines photovoltaic (or wind) electricity with concentrated solar heat. It envisages an investment of 2.7 million euros.
“The heart of the PROMETEO challenge” explains Alberto Giaconia, the ENEA researcher who coordinates the project, “lies in ensuring continuity in the production of hydrogen from electrolysis even when renewable energy from solar sources is not available due to intermittency or in periods in which it is more convenient to use it, such as in production surpluses; this will allow us to be highly competitive in terms of costs “,
So Giorgio Graditi, Director of the ENEA Department of Energy Technologies and Renewable Sources: “A bit like the mythological Prometheus who stole fire from the gods to give it to humanity, this project represents a great challenge for us towards production and use. of green hydrogen in the industrial sector. The decarbonization goals to 2030 and 2050 require research to find new ways to produce and exploit renewable sources optimally and on a large scale. And green hydrogen has all the characteristics to support the energy transition ”.
The project involves the construction in Italy of a prototype of a 25 kWe solid oxide electrolyser capable of producing 15 kg of hydrogen per day, which will later be validated in Spain at a photovoltaic plant. “It is desirable – concludes Graditi – that at the end of the project the prototype will also be installed in our Hydrogen Valley of the Casaccia Research Center, to facilitate its technology transfer to the Power-to-Gas sector”.
“The first big challenge – underlines Dina Lanzi, Head of Technological Development of Snam’s hydrogen business unit – is to produce hydrogen with zero emissions on a large scale and at low costs to decarbonise the energy-intensive industry and heavy mobility. The PROMETEO project will contribute to developing and scaling efficient production technologies thanks to high temperatures, reducing the production costs of green hydrogen and increasing its competitiveness. The second objective is to integrate this technology into the energy infrastructure, coupling the gas network and the electricity network, to overcome the current and future challenges of the Italian and European energy system. We are happy to have contributed to this initiative by pooling our infrastructural and technological skills from a supply chain perspective “.
“The PROMETEO project” declares Luigi Crema, Director of the FBK Sustainable Energy Center “represents an excellent opportunity for the development of the Italian industrial chain in the green hydrogen sector, in close connection with the European industry. PROMETEO will be an important step in building the decarbonization mosaic in Europe, especially in the industrial sectors most involved in the energy transition such as energy, chemicals and in particular nitrogen fertilizers. It is a great challenge that we will face with passion and dedication “,
“PROMETEO is an important project” adds Barbara Morico, Project Manager for NextChem “which is part of the green hydrogen initiatives that NextChem is carrying out, and is aimed at developing a new process based on electrolysis technology to solid oxides at high temperatures. PROMETEO represents a very important phase towards decarbonization as it aims to implement the integration of the water electrolysis process with renewable energies (solar, photovoltaic, wind). NextChem, within the Consortium, is the partner responsible for the realization of the prototype for the demonstration of the technology, also contributing to the definition of scale-up strategies on an industrial basis “.