English: Solar eruptive events affect the close neighbourhood of the Earth. They also affect human infrastructure, power grids mainly, due to the induction of electrical currents. Only recently the attention was drawn not only to large flares, but also to estimate the long-term effects of increased solar activity by statistical methods. We analyse the failure rates in the main Czech power transmission system operated by the Czech national operator v{C}EPS. We show that the effects of solar activity on failure rate in the main Czech power grid cannot be excluded even for central-european country. This is a preliminary study. Czech: Eruptivni projevy slunev{c}ni aktivity ovlivv{n}uji bezprostv{r}edni kosmicke okoli nav{s}i Zemv{e} a postihuji prostv{r}ednictvim indukce elektrickych proudr{u} i pozemskou infrastrukturu, zejmena rozvodne sitv{e} silove elektv{r}iny. Teprve v poslednich letech byla vv{e}novana pozornost nejen hodnoceni bezprostv{r}ednich dopadr{u} silnych eruptivnich udalosti na zav{r}izeni rozvodne sitv{e}, ale take statistickemu zhodnoceni vlivu zvyv{s}ene slunev{c}ni aktivity. Ve spolupraci s v{C}EPS, a.s., jsme statisticky vyhodnotili v{c}etnost zavad na zav{r}izenich patev{r}ni rozvodne sitv{e} v{C}R v zavislosti na urovni slunev{c}ni aktivity a ukazujeme, v{z}e vliv nahlych eruptivnich udalosti na zavadovost zav{r}izeni v{c}eske rozvodne sitv{e} nelze vylouv{c}it.