Byproducts are generated in large quantities because of increase in biofuel production demand.Improper handling of such material can cause serious environmental problems.Biochar can be produced through carbonization of such byproducts, which can be used as a soil amendment.A pot experiment on rice was carried.Soil type was selected as sandy soil.Three different byproducts of biogas were used, which were categorised as biochar, dehydrated filtrate,and concentrated filtrate.Their effect was compared to ammonium sulphate which was used as chemical fertilizer.Addition of byproducts as a fertilizer resulted in more crop yield.However, more methane production from all three byproducts was observed than ammonium sulphate.