No abstract

In this paper, the authors elaborated on the conversion of excess electricity, generated from renewable energy sources by water electrolysis, into chemical energy and on its underground storing. Specifically, one of potential solutions in the function of transition and decarbonization of the energy sector is a project of conversion and storage of wind and solar energy, that is, underground storage of chemical energy (hydrogen). In the primary cycle of producing and storing hydrogen, underground storing of hydrogen (UHS) in geological formations is a crucial factor in storing large volumes of energy for a theoretically longer, or an indefinite period. The paper presents possibilities of using the stated technology in Croatia by using a small standard underground gas storage facility (UGS). The article presents technical-technological process of producing and underground storing of hydrogen: from generating electricity through renewable energy sources or other industrial processes generating waste energy, the production of hydrogen and its compression, transport and storage in underground geological formations. In this paper, the authors will also elaborate on the status of the EU States´ regulations, which present the main factor for the previously mentioned activities, as well as on the necessary changes that the relevant regulations need to undergo.

During mass blasting, seismic effects occur that can significantly damage existing buildings near the blasting site, depending on the amount of explosives and the blasting distance itself. An additional problem during blasting is the facilities located in the critical zone of mining works -the problem of unpredictable behavior of the soil or rock in relation to the propagation of seismic waves. Based on the measurements performed on the example presented in this paper at the site of the quarry EP "Zvečaj" (minefield at the level of the second floor K + 163 to K + 179), the method is explained, how quality and well-conducted research can determine optimal amounts of explosives per ignition level. Based on the performed measurement procedures and processed data, measured and obtained results of values of soil oscillation velocities in the direction of populated areas caused by production blasting in the quarry EP "Zvečaj", it follows that the conducted mining activity, consequently, had no damage. Blasting significantly affects the environment, due to the emission of noise and seismic action, which is manifested in the form of oscillations and elastic deformations of the rock, which is an artificial earthquake in which the place of explosion is its epicenter.