Feasibility of usage of hemp as a feedstock for anaerobic digestion: Findings from a literature review of the relevant technological and energy dimensions

Renewable biomasses are used worldwide as inputs for energy production through processes, like Anaerobic Digestion (AD), which is a well-established technology to transform them into bio-gas and other by-products. Maize, triticale, sunflower and sorghum are energy crops frequently used as feedstocks in AD applications, mainly because of their high biogas potential. However, their cultivation generates some negative environmental impacts due to the direct and indirect land use changes. Therefore, it is important to seek for alternative species to replace some of them with others with lower environmental impacts while producing comparable biogas and energy yields. Industrial Hemp (IH) was documented in this literature review to be a suitable crop for AD applications with yields that are highly competitive with those of the energy crops being used now. Additionally, this literature review provided insight into the diversity of the methane yielding parts of the IH plants, with fresh leaves yielding the highest quantities. Finally, the authors of this literature review highlighted the need for research and development designed to expand the usage of IH as green biomass in AD plants, for efficient production of biogas and organic nutrients, and thereby, contributing to transitioning toward low fossil-carbon footprint societies.