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The Fuel Cells and Hydrogen (FCH) technologies will play an important role in a future where greenhouse gasses emissions need to be reduced. Nevertheless, a huge implementation of these technologies must be addressed taking into account an eco friendly scope not only from the manufacturing perspective but also from the end-of-life scope. A classification of the materials has been done considering the importance of each of them. To obtain a complete overview of the problem, different criteria have been compared: the cost, the scarcity of the material and the affections these materials can cause not only to the environment but also to the humans. This classification has been used to identify which are the most critical materials. Moreover, other transversal issues have been studied as the regulations that apply to FCH technologies from a paneuropean perspective and the strategies to face the end-of-life of this equipment. A holistic point of view has been considered in order to see how the process of dismantling and recycling faces different problems and which milestones to achieve in a future with a deep market penetration are.

V diplomski nalogi smo s pomočjo študije življenjskih ciklov ovrednotili okoljske vplive proizvodnje 1 kilograma vodika. Za vrednotenje okoljskih vplivov smo uporabil program GaBi. Z uporabo okoljskih kazalcev metodologije Environmental Footprint - EF 3.0 smo določili, katere tehnologije proizvodnje vodika imajo večji vpliv na okolje ter katere tehnologije so najbolj prijazne okolju. Najčistejši izmed vseh načinov proizvodnje vodika je vodik, ki nastaja kot stranski produkt pri proizvodnji kloroalkalnih snovi. Temu načinu proizvodnje vodika sledi vodik, ki je proizveden s tehnologijo krekinga in vodik proizveden z parnim reformiranjem zemeljskega plina. Največji vpliv na okolje ima vodik, ki je pridobljen z elektrolizo vode, kjer je vhodna električna energija pridobljena pretežno iz jedrskih, hidro in termo elektrarn. In this thesis we analysed environmental impacts of producing 1 kg of hydrogen. We did it using life cycle assessment. We used GaBi software for evaluating environmental impacts. With usage of environmental indicators from methodology Environmental Footprint – EF 3.0 we defined which hydrogen production technologies have the biggest and which the smallest impact on the environment. The cleanest hydrogen is the one produced as a by-product from chlor-alkali production. Hydrogen produced with cracking and steam reforming of natural gas follows. The biggest impact on the environment has electrolysis of water, in which the input electric energy is produced mainly from nuclear, hydro and thermal power plants.

Potrebe po energiji naraščajo, hkrati pa ostaja težnja po uporabi zelenih virov energije. Vodikove tehnologije ponujajo številne prednosti in se v tem trenutku zdijo primerna rešitev za zadostitev okoljskih zahtev. V nalogi so pregledane aktualne tehnologije elektrolizerjev, na podlagi katerih so postavljeni numerični modeli za študijo življenjskih ciklov posameznih tehnologij in njihova medsebojna primerjava okoljskih vplivov ob proizvodnji 1 kg vodika z uporabo električne energije iz virov v Sloveniji. Ugotovljeno je bilo, da je faza obratovanja elektrolizerjev bistvenega pomena iz vidika okoljskih vplivov, ter da je izbira vira električne energije odločujoča. Najbolj smiseln vir za napajanje elektrolizerja je hidro energija, medtem ko ni smiselno uporabljati slovenske energijske mešanice. The needs for energy are growing, but a tendency to use green energy sources is the same. Hydrogen technologies offer many advantages and so far seem to be a suitable solution to meet environmental requirements. This work examines current technologies of electrolysers, based on which numerical models for life cycle assessment of individual technologies are set up. A mutual comparison between technologies is made regarding production of 1 kg of hydrogen. It was found that the operation phase of electrolysers is the most critical from the point of view of environmental impacts, and that the choice of Slovenian energy source is decisive. The most sensible source to power an electrolyzer is hydro energy, while it does not make sense to use a Slovenian energy mix.

Ko govorimo o prihodnosti pridobivanja električne energije in o ogljični neodvisnosti, je zelena energija pomembna tema. Vodik velja kot rešitev, težava pa nastane pri proizvodnji vodika s pomočjo obstoječih virov energije. Vplive na okolje zaradi proizvodnje vodika bomo ocenili s pomočjo študije življenjskih ciklov (LCA), pri tem pa bomo upoštevali slovensko mešanico pridobivanja el. energije, samo hidroelektrarne in samo jedrsko elektrarno. Rezultate bomo prikazali za proizvodnjo 1 kg vodika. Programsko orodje, ki ga bomo uporabili za izdelavo modela, je GaBi Thinkstep, ocena za prikaz okoljskih vplivov pa je metoda Environmental Footprint – EF (3.0). Rezultati so pokazali, da ima najnižje vrednosti okoljskih indikatorjev NEK, za tem hidroelektrarna, najslabše pa ima slovenska energijska mešanica, kar je logično, saj je v to vključena tudi uporaba termoelektrarn, ki za gorivo uporabljajo premog. Ugotovili smo, da pridelava vodika s trenutno slovensko mešanico z vidika okoljskih vplivov ni posebno zelena. Večino onesnaževanja povzroča elektroliza. Okoljske kazalce bi močno znižali z izgradnjo drugega bloka jedrske elektrarne. When we talk about the future of electricity generation and carbon independence, green energy is an important topic. Hydrogen is considered a solution, and the problem arises in the production of hydrogen using existing energy sources. Environmental impacts due to hydrogen production will be assessed using a life cycle study (LCA), considering the Slovenian mixture of electricity generation hydropower and nuclear power. The results will be shown fort the production of 1 kg of hydrogen. The software tool we will use to create the model is GaBi Thinkstep, and the assessment to show environmental impacts is the Environmental Footprint – EF (3.0) method. The results showed that the Krško nuclear power plant has the lowest values of environmental indicators, followed by a hydroelectric power plant, and the Slovenian energy mix has the worst, which is logical, since this also includes the use of thermal power plants that use coal as fuel. We found that the production of hydrogen with the current Slovenian mixture is not particularly green in terms of environmental impacts. Most of the pollution is caused by the electrolysis process.