The circular economy offers a new product-waste-product model, in this case obtaining biofuels from rye biomass. The circular economy introduces a new product design, which will enable its functionality for a longer period of use. Secale cereale L. is an economically important crop for food, feed and bioenergy. The objective of this study was to estimate productivity of rye genotypes and the possibility of obtaining biogas from rye biomass during two growing seasons, 2019-2020. The aim of this study was to examine the influence of year and genotype on rye productivity parameters, biogas, methane yield, methane proportion, and the possibility of using rye as an alternative fuel in Serbia. The influence of the year and genotypes on the parameters of rye productivity, biogas and methane yield, methane content and the possibility of using rye as an alternative fuel in Serbia was investigated. Genotype and year × genotype interaction had a statistically significant effect on biogas yield, methane yield and methane content in the studied rye genotypes. Genotype G1 had the mean of green biomass yield (25.73 t ha -1 ) significantly higher compared to genotype G2 (23.75 t ha -1 ) in both years of experiment. Green biomass yield (24.11 t ha -1 ) was better in 2019 compared to 2020. Biogas yield varied from 260.57 m 3 ha -1 (genotype G1) to 214.58 m 3 ha -1 (genotype G2). Biogas yield were better in 2019

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