Solar originating events are repeatedly observable in cosmic ray flux measured at the ground by neutron monitors. We analyze time intervals of halo coronal mass ejections (CMEs), as well as sudden storm commencements (SSCs) appearance during solar cycle 24. We consider neutron monitor data, as well as, solar, heliospheric and geomagnetic activity parameters, around those periods, using different mathematical tools. Our computations show that the fractal dimension calculated for each week of studied period, based on Oulu neutron monitor hourly data, decreases around those events. Skewness and kurtosis change abruptly from the background average value.
Since an influence of space weather phenomena on energy infrastructure is well known, in the next step we consider a list of electrical grids failures which occurred in southern Poland during the studied time intervals of halo CMEs and SSCs occurrence. Based on the data from Institute of Meteorology and Water Management-Polish National Research Institute we exclude from the analysis failures caused by the meteorological effects.