Almost at the same time came the announcement that the hydrogen pipeline will be extended to Germany.
French President Emmanuel Macron said so during a press conference in Paris alongside German Chancellor Olaf Scholz, on the occasion of the celebrations for the sixtieth anniversary of the Élysée Treaty.
“The H2Med project”, Macron said, “thanks to European funding, will link Portugal, Spain and France with Germany, which will be a partner in this hydrogen infrastructure”.
By the admission of the signatories themselves, it is an “ambitious” and “rapid” European response to the Inflation Reduction Act (IRA), a legislative package of around 400 billion dollars allocated by US President Joe Biden which, from 1 January 2023, will support businesses and households in the green transition.
The commitment made by the European leaders is indeed to create a “green energy corridor” that meets the requirements of the ecological transition. The countries have pledged to transport only “green hydrogen”, that is, hydrogen produced exclusively with renewable energy: a requirement for access to European funding.
It is no small commitment, considering that to this day producing “green hydrogen” remains more expensive than producing “grey hydrogen”, which is obtained using fossil fuels. Spain, however, assures that by 2030 green hydrogen will be competitively priced and will become even cheaper than grey hydrogen by 2050, thanks above all to the development of photovoltaics in the south of Spain.
Hydrogen at the centre of the debate on new energy sources
Hydrogen, then, is back at the centre of the debate on decarbonising the economy. But with what realistic prospects?
Hydrogen is an abundant element and, in its pure gaseous form (H2), it is a fuel that burns in a similar way to other gases such as methane. Compared with other traditional fuels, it has the highest energy content per unit of weight (up to three times higher than petrol). Moreover, the process produces no polluting emissions or CO2, simply water.
The point, however, is that hydrogen is not available in nature in a form useful for energy purposes (as H2 molecules in gaseous form): it has to be produced artificially from compounds in which it is bound, such as methane or water, expending energy from primary energy sources.
This use of energy for the extraction process entails economic and environmental costs (such as polluting emissions and resource depletion), unless renewable sources are used to produce it. There is also the risk of making the complete cycle thermodynamically disadvantageous (more energy is used than is obtained).
Compared with production from methane (reforming) or from coal gasification, the least polluting hydrogen extraction process is the one from water (electrolysis), if energy produced from renewable sources is used.
It is precisely the diversity of extraction sources and their environmental compatibility that defines the “famous” colour scale of hydrogen production: green hydrogen, if produced by electrolysis powered by renewable energy; grey, if extracted from methane or other hydrocarbons; blue, if extracted from hydrocarbons and associated with CO2 capture and storage systems; purple or pink, produced by electrolysis of water using electricity generated by nuclear power; and black, if extracted from water using electricity produced by a coal- or oil-fired power station.
