Fig. (4) Impact of (a) estimation method and (b) productivity rates of sweet sorghum on values of potential ethanol yield. Graph (a) is based on the equation by Smith et al. [37]; (b) – based on the equation by Somani et al. [38]. Estimation ‘in the present study’ is based: (a) – on the maximal value of sugar yield - 9.5 t/ha, recorded during soil supplementation experiments; (b) – on the average and maximum ethanol yield from the same experiment (excluding control, Table 8).