An ambitious project in “Hard-To-Abate” chemistry: producing hydrogen with hydroelectric energy

In late October 2022, the Ministry of Environment and Energy Security allocated 1 billion euros to promote research, development, and innovation in the field of industrial processes, with the aim of developing initiatives for the use of hydrogen in industrial sectors that use methane as a source of thermal energy supporting, at the same time, the production of electrolytic hydrogen from renewable energy sources. The stated goal of this important initiative is to promote the introduction of hydrogen into industrial processes to decarbonize so-called “hard-to-abate” sectors, which are the most polluting and difficult to convert, such as the chemical sector.

Esseco Industrial is one of the few national chemical companies that can be considered environmentally sustainable since it uses renewable energy (mainly hydroelectric and solar) for over 51% of its electrical consumption (data for the first half of 2023). Through its operating companies – Altair Chimica, Hydrochem Italia, and Esseco – it has long been committed to a gradual but rapid transition to renewable energy sources and is currently developing some investment project proposals. It’s worth noting that in 2022, at the Hydrochem production site, the percentage of renewable electricity used in the production cycle exceeded 66% on an annual basis.

The company is not new to this kind of experience: in Saline di Volterra (PI), Altair Chimica already recovers hydrogen from the electrolysis of brine (saltwater) for steam generation without any harmful emissions, replacing natural gas (methane CH4), which generates CO2 when burned. To this end, a bi-fuel steam generator has been built capable of operating on hydrogen, methane, or a mix of the two, completely automated based on the instant availability of hydrogen from electrolysis. Modulation occurs automatically based on the available hydrogen to maximize its reuse.

Also in Pieve Vergonte (VB), Hydrochem Italia produces hydrogen from the electrolysis of brine, and the residue from its use in the production of hydrochloric acid is used to reduce the consumption of methane for steam generation in the distillation column. In Pieve, the new IdroHydro project could see the light if the application submitted to the “Hard-to-Abate” call for proposals is accepted. This project involves the construction of a new hydroelectric power plant capable of producing over 20,000 MWh of green energy annually. Of these, only 600 MWh/year will be used for the normal functions of the plant due to their lower power requirement. The majority will be used to power a 6 MW electrolyzer with a production capacity of 1,190 million Nm3/h (Normal Cubic Metres Per Hour) of hydrogen at full load (359 t/year). This hydrogen will be used in two boilers currently in operation in Pieve, which would be converted from pure methane to bi-fuel (methane, hydrogen, or a mix of the two).

Associating hydrogen production with renewable energy sources such as hydroelectric power will allow for much higher production. It’s worth noting that to achieve the same results through other green sources, approximately 20 MW of photovoltaic power would be required, for example. The IdroHydro project, on the other hand, allows for the full use of energy throughout the day, thus ensuring greater operation of the electrolysis plant. With this approach, it will be possible to save over 1.2 million Sm3/h (Standard Cubic Metres Per Hour) of methane per year, which is about 24% of the total methane used.

The project’s outline is summarized in the following image:

The IdroHydro project for hydrogen production from renewable sources has been designed in full coherence with the objectives of the Ministry of Environment and Energy Security‘s “Hard-to-Abate” call for proposals. The expected investment is approximately 27 million euros, mostly allocated to the construction of the new hydroelectric power plant and the new electrolyzer, with only 0.6 million euros allocated to the bi-fuel boilers.

While awaiting evaluations by the relevant authorities, we hope that this great opportunity, linked to the National Recovery and Resilience Plan (PNRR), can soon become a new reality that combines energy benefits with environmental advantages.