In the Experimental Station of National Research Institute of Animal Production in Grodziec Śląski we have conducted the scientific researches about renewable energy sources on agricultural origin. One of them is a cultivation on the area of 18,25 ha energetic willow Salix viminalis. The researches have started seven years ago and their main goal was to determine ecologic and economic effects. The were conducted on eight allotments in next four years of willow growth and following parameters were defined: gain (yielding), heavy metals absorption (Pb, Cd), energetic value, and technology of crops. It was concluded that yielding and energetic values on particular allotments were differentiated. The content of heavy metals was also differentiated, the highest lead content was on the allotments situated near to communications route (highway S1), in turn on allotments no II near to fish ponds cadmium content was insignificant. Two ways of willow crops were compared - one- and two phases. Changeability of regulation regarding energetic crops hang in a balance their profitability.