The effect of total energy consumption and electric energy consumption on cumulated noxiousness index (SWU) value of coke production process, steel rolled goods and PVC windows profiles is presented in the paper. Using the sequential analysis it was proved that in SWU of the prediction process, from the stage of law materials to the final product, the onerousness connected with energy consumption amounts from 70% up to 81%, whereas that connected with electric energy directly or indirectly consumed - from 60% up to 77%.