Hydrogen power plant, does it really make sense?

Hydrogen power station between new and old projects

(Rinnovabili.it) – Not everyone knows it, but in the period from 2010 to 2018, Italy was able to boast a commendable world record: for eight years in Fusina (Venice) it was in operation The first hydrogen power station Industrial level achieved in the world. The combined cycle plant used 1.3 tons of hydrogen per hour, which was generated as a byproduct of the production cycle at the Marghera petrochemical plant. Although the origin of the aircraft carrier is far from clean, it represented a unique technological model at the national level (and beyond). The structure was created to verify the technical feasibility of the projectUse of pure hydrogen in gas turbinesHowever, it was suspended the day after the production cycle that fed it was closed.

Today, 5 years later, the push towards hydrogen is stronger than ever and in Europe, as in Italy, the idea of ​​creating Green H2 thermoelectric power plants She has found a specific space of her own. Germany is serious about this matter above all else. The German government is preparing a series of tenders to build new power plants with a capacity of 23.8 gigawatts, including 8.8 gigawatts “hydrogen ready” and 15 gigawatts of natural gas, to be converted in the future.

There is no shortage of projects in the Bel Paese area either. In November 2022 Sanam has successfully completed some tests At its natural gas compression plant in Istrana (Treviso), with the aim of experimenting with the use of hydrogen to produce electricity. The project required the installation of a custom-designed NovaLT12 (12 MW) turbine from Baker Hughes.

Green hydrogen power plants, future challenges

But does it really make sense to build a hydrogen power plant? What challenges do we have to overcome before the solution becomes economically and energetically viable? The answer is A A new study conducted by the Rainer Lemoine Institute Which compares current definitions of H2 power plants are ready (literally “H2-ready”), which describes the technical requirements for operation and potential costs of converting gas systems.

The reference economy is Germany, but the results could provide important food for thought for Italy as well. The authors believe that hydrogen should be used in power plants Only when there are no “more efficient alternatives”. “Green hydrogen is a scarce commodity in the near future and will have to be largely imported. The combined efficiency of the electrolysis and power plant is only 36% If each of the individual techniques has a return of 60%. In this context, hydrogen electricity generation should only be used if no better alternatives are available.reads the report.

What does “hydrogen ready” mean?

It should be borne in mind that at the moment we are still talking about ““Hydrogen is ready” (Even if there is no common European definition), what does it mean? The plants are ready, one day, to be completely transferred to the conveyor. The outlook is necessarily directed towards the future because Industrial-sized gas turbines powered by 100% hydrogen. They are not yet commercially available. The TRL for these devices is currently 7, which indicates pre-commercial demonstration status.

One of the first steps recommended by scientists is to work at the national level, or better yet, at the community level Definition of “H2 readiness” Related to the costs of all power plants, both those that handle the basic load and those that provide the maximum load. They also suggest In favor of cogeneration plants Able to provide its full electrical capacity at any time, regardless of thermal demand.

New rules for hydrogen power plants

One aspect that cannot be missed is the organizational aspect. Scientists warn of the necessity of doing this work Create custom technical rules and standards For hydrogen power plant. “As for Limit values ​​for nitrogen oxides (NOx) It should be taken into account that when combustion of H2 the formation of nitrogen oxides is greater than in natural gas. In combined cycle systems, after cooling the exhaust gases, a denitrification unit with an automatic catalytic reaction can be installed in the heat recovery boiler to reduce NOx emissions to usual limit values. For gas turbines without a thermal boiler, this is not currently possible, as exhaust gas temperatures are too high for catalytic converters.