Iva Urbanová’s scientific contributions

Securing new sources of renewable energy and achieving national self-sufficiency in natural gas have become increasingly important in recent times. The study described in this paper focuses on three geologically diverse underground gas reservoirs (UGS) that are the natural habitat of methane-producing archaea, as well as other microorganisms with which methanogens have various ecological relationships. The objective of this research was to describe the microbial metabolism of methane in these specific anoxic environments during the year. DNA sequencing analyses revealed the presence of different methanogenic communities and their metabolic potential in all sites studied. Hydrogenotrophic Methanobacterium sp. prevailed in Lobodice UGS, members of the hydrogenotrophic order Methanomicrobiales predominated in Dolní Dunajovice UGS and thermophilic hydrogenotrophic members of the Methanothermobacter sp. were prevalent in Tvrdonice UGS. Gas composition and isotope analyses were performed simultaneously. The results suggest that the biotechnological potential of UGS for biomethane production cannot be neglected.

Employing deep reservoirs as UGS (underground gas storage) has a long history across continents. In 2018, 689 underground gas reservoirs with a total volume of 417 bcm were in operation worldwide. It is known that many microbial processes take place in the deep underground, even under the conditions of underground gas reservoirs. In this review, we focus mainly on methanogenesis and discuss related topics such as optimal environmental conditions, description of different types of UGS and microbial communities inhabiting these environments. We elucidate the potential of UGS as natural bioreactors for non-fossil methane production in the context of Power to Methane technology and the extension/expansion of the low-carbon economy. The role of carbon-neutral methane in the energy mix is likely to play a significant role in the coming decades. The safe production, transportation and storage of methane are well managed as well the existing infrastructure has been in place for a long time without problems. We also have experience in the long-term operation of underground gas storage systems. Methane technology thus appears to be a very promising approach and, together with the functioning UGS infrastructure, could be an important step towards the potential use of biomethanation in underground gas storage facilities as a way to reduce greenhouse gas emissions in the future.