Analysis of factors influencing energy efficiency of biogas plants

Abstract

The number of biogas plants in Latvia has decreased by 9 plants, from 56 in 2017 to 47 in 2022. One of the reasons for this decrease in the number of biogas plants is low energy efficiency. The energy efficiency factor is influenced by different factors. Factors influencing the operation of the 49 biogas plants in 2020 were assessed, including the factor Installed electric power that is not changeable by the plant operator. Other factors constitute a group of factors that can be compensated in daily operation like a proportion of input biomass. The parameters of all factors were analyzed using statistical methods. Results of analyses show that there is no single factor having the effect on the capacity factor with statistically acceptable reliability. However, correlation analyses and the obtained linear regression revealed two most significant factors, i.e. the proportion of manure (MA) and proportion of silage (SIL) in feedstock whose combination gives statistically significant linear equation for assessment of changes in the capacity factor (CF) MAof biogas plant. This two-factor model can be used to evaluate the capacity factor of a biogas plant with a combined input of manure and silage in Latvia.